Sample records for implement two-party protocols

  1. Two-party secret key distribution via a modified quantum secret sharing protocol.

    PubMed

    Grice, W P; Evans, P G; Lawrie, B; Legré, M; Lougovski, P; Ray, W; Williams, B P; Qi, B; Smith, A M

    2015-03-23

    We present and demonstrate a novel protocol for distributing secret keys between two and only two parties based on N-party single-qubit Quantum Secret Sharing (QSS). We demonstrate our new protocol with N = 3 parties using phase-encoded photons. We show that any two out of N parties can build a secret key based on partial information from each other and with collaboration from the remaining N - 2 parties. Our implementation allows for an accessible transition between N-party QSS and arbitrary two party QKD without modification of hardware. In addition, our approach significantly reduces the number of resources such as single photon detectors, lasers and dark fiber connections needed to implement QKD.

  2. Quantum secret information equal exchange protocol based on dense coding

    NASA Astrophysics Data System (ADS)

    Jiang, Ying-Hua; Zhang, Shi-Bin; Dai, Jin-Qiao; Shi, Zhi-Ping

    2018-04-01

    In this paper, we design a novel quantum secret information equal exchange protocol, which implements the equal exchange of secret information between the two parties with the help of semi-trusted third party (TP). In the protocol, EPR pairs prepared by the TP are, respectively, distributed to both the communication parties. Then, the two parties perform Pauli operation on each particle and return the new particles to TP, respectively. TP measures each new pair with Bell basis and announces the measurement results. Both parties deduce the secret information of each other according to the result of announcement by TP. Finally, the security analysis shows that this protocol solves the problem about equal exchange of secret information between two parties and verifies the security of semi-trusted TPs. It proves that the protocol can effectively resist glitch attacks, intercept retransmission attacks and entanglement attack.

  3. Secret Key Generation via a Modified Quantum Secret Sharing Protocol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smith IV, Amos M; Evans, Philip G; Lawrie, Benjamin J

    We present and experimentally show a novel protocol for distributing secret information between two and only two parties in a N-party single-qubit Quantum Secret Sharing (QSS) system. We demonstrate this new algorithm with N = 3 active parties over 6km of telecom. ber. Our experimental device is based on the Clavis2 Quantum Key Distribution (QKD) system built by ID Quantique but is generalizable to any implementation. We show that any two out of the N parties can build secret keys based on partial information from each other and with collaboration from the remaining N > 2 parties. This algorithm allowsmore » for the creation of two-party secret keys were standard QSS does not and signicantly reduces the number of resources needed to implement QKD on a highly connected network such as the electrical grid.« less

  4. Semi-quantum Dialogue Based on Single Photons

    NASA Astrophysics Data System (ADS)

    Ye, Tian-Yu; Ye, Chong-Qiang

    2018-02-01

    In this paper, we propose two semi-quantum dialogue (SQD) protocols by using single photons as the quantum carriers, where one requires the classical party to possess the measurement capability and the other does not have this requirement. The security toward active attacks from an outside Eve in the first SQD protocol is guaranteed by the complete robustness of present semi-quantum key distribution (SQKD) protocols, the classical one-time pad encryption, the classical party's randomization operation and the decoy photon technology. The information leakage problem of the first SQD protocol is overcome by the classical party' classical basis measurements on the single photons carrying messages which makes him share their initial states with the quantum party. The security toward active attacks from Eve in the second SQD protocol is guaranteed by the classical party's randomization operation, the complete robustness of present SQKD protocol and the classical one-time pad encryption. The information leakage problem of the second SQD protocol is overcome by the quantum party' classical basis measurements on each two adjacent single photons carrying messages which makes her share their initial states with the classical party. Compared with the traditional information leakage resistant QD protocols, the advantage of the proposed SQD protocols lies in that they only require one party to have quantum capabilities. Compared with the existing SQD protocol, the advantage of the proposed SQD protocols lies in that they only employ single photons rather than two-photon entangled states as the quantum carriers. The proposed SQD protocols can be implemented with present quantum technologies.

  5. Practical quantum appointment scheduling

    NASA Astrophysics Data System (ADS)

    Touchette, Dave; Lovitz, Benjamin; Lütkenhaus, Norbert

    2018-04-01

    We propose a protocol based on coherent states and linear optics operations for solving the appointment-scheduling problem. Our main protocol leaks strictly less information about each party's input than the optimal classical protocol, even when considering experimental errors. Along with the ability to generate constant-amplitude coherent states over two modes, this protocol requires the ability to transfer these modes back-and-forth between the two parties multiple times with very low losses. The implementation requirements are thus still challenging. Along the way, we develop tools to study quantum information cost of interactive protocols in the finite regime.

  6. Secure multi-party communication with quantum key distribution managed by trusted authority

    DOEpatents

    Nordholt, Jane Elizabeth; Hughes, Richard John; Peterson, Charles Glen

    2013-07-09

    Techniques and tools for implementing protocols for secure multi-party communication after quantum key distribution ("QKD") are described herein. In example implementations, a trusted authority facilitates secure communication between multiple user devices. The trusted authority distributes different quantum keys by QKD under trust relationships with different users. The trusted authority determines combination keys using the quantum keys and makes the combination keys available for distribution (e.g., for non-secret distribution over a public channel). The combination keys facilitate secure communication between two user devices even in the absence of QKD between the two user devices. With the protocols, benefits of QKD are extended to multi-party communication scenarios. In addition, the protocols can retain benefit of QKD even when a trusted authority is offline or a large group seeks to establish secure communication within the group.

  7. Secure multi-party communication with quantum key distribution managed by trusted authority

    DOEpatents

    Hughes, Richard John; Nordholt, Jane Elizabeth; Peterson, Charles Glen

    2015-01-06

    Techniques and tools for implementing protocols for secure multi-party communication after quantum key distribution ("QKD") are described herein. In example implementations, a trusted authority facilitates secure communication between multiple user devices. The trusted authority distributes different quantum keys by QKD under trust relationships with different users. The trusted authority determines combination keys using the quantum keys and makes the combination keys available for distribution (e.g., for non-secret distribution over a public channel). The combination keys facilitate secure communication between two user devices even in the absence of QKD between the two user devices. With the protocols, benefits of QKD are extended to multi-party communication scenarios. In addition, the protocols can retain benefit of QKD even when a trusted authority is offline or a large group seeks to establish secure communication within the group.

  8. Secure multi-party communication with quantum key distribution managed by trusted authority

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hughes, Richard John; Nordholt, Jane Elizabeth; Peterson, Charles Glen

    Techniques and tools for implementing protocols for secure multi-party communication after quantum key distribution ("QKD") are described herein. In example implementations, a trusted authority facilitates secure communication between multiple user devices. The trusted authority distributes different quantum keys by QKD under trust relationships with different users. The trusted authority determines combination keys using the quantum keys and makes the combination keys available for distribution (e.g., for non-secret distribution over a public channel). The combination keys facilitate secure communication between two user devices even in the absence of QKD between the two user devices. With the protocols, benefits of QKD aremore » extended to multi-party communication scenarios. In addition, the protocols can retain benefit of QKD even when a trusted authority is offline or a large group seeks to establish secure communication within the group.« less

  9. Two-Party secret key distribution via a modified quantum secret sharing protocol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Grice, Warren P.; Evans, Philip G.; Lawrie, Benjamin

    We present and demonstrate a method of distributing secret information based on N-party single-qubit Quantum Secret Sharing (QSS) in a modied plug-and-play two-party Quantum Key Distribution (QKD) system with N 2 intermediate nodes and compare it to both standard QSS and QKD. Our setup is based on the Clavis2 QKD system built by ID Quantique but is generalizable to any implementation. We show that any two out of N parties can build a secret key based on partial information from each other and with collaboration from the remaining N 2 parties. This method signicantly reduces the number of resources (singlemore » photon detectors, lasers and dark ber connections) needed to implement QKD on the grid.« less

  10. Two-Party secret key distribution via a modified quantum secret sharing protocol

    DOE PAGES

    Grice, Warren P.; Evans, Philip G.; Lawrie, Benjamin; ...

    2015-01-01

    We present and demonstrate a method of distributing secret information based on N-party single-qubit Quantum Secret Sharing (QSS) in a modied plug-and-play two-party Quantum Key Distribution (QKD) system with N 2 intermediate nodes and compare it to both standard QSS and QKD. Our setup is based on the Clavis2 QKD system built by ID Quantique but is generalizable to any implementation. We show that any two out of N parties can build a secret key based on partial information from each other and with collaboration from the remaining N 2 parties. This method signicantly reduces the number of resources (singlemore » photon detectors, lasers and dark ber connections) needed to implement QKD on the grid.« less

  11. Continuous-variable protocol for oblivious transfer in the noisy-storage model.

    PubMed

    Furrer, Fabian; Gehring, Tobias; Schaffner, Christian; Pacher, Christoph; Schnabel, Roman; Wehner, Stephanie

    2018-04-13

    Cryptographic protocols are the backbone of our information society. This includes two-party protocols which offer protection against distrustful players. Such protocols can be built from a basic primitive called oblivious transfer. We present and experimentally demonstrate here a quantum protocol for oblivious transfer for optical continuous-variable systems, and prove its security in the noisy-storage model. This model allows us to establish security by sending more quantum signals than an attacker can reliably store during the protocol. The security proof is based on uncertainty relations which we derive for continuous-variable systems, that differ from the ones used in quantum key distribution. We experimentally demonstrate in a proof-of-principle experiment the proposed oblivious transfer protocol for various channel losses by using entangled two-mode squeezed states measured with balanced homodyne detection. Our work enables the implementation of arbitrary two-party quantum cryptographic protocols with continuous-variable communication systems.

  12. Experimental Quantum Coin Tossing

    NASA Astrophysics Data System (ADS)

    Molina-Terriza, G.; Vaziri, A.; Ursin, R.; Zeilinger, A.

    2005-01-01

    In this Letter we present the first implementation of a quantum coin-tossing protocol. This protocol belongs to a class of “two-party” cryptographic problems, where the communication partners distrust each other. As with a number of such two-party protocols, the best implementation of the quantum coin tossing requires qutrits, resulting in a higher security than using qubits. In this way, we have also performed the first complete quantum communication protocol with qutrits. In our experiment the two partners succeeded to remotely toss a row of coins using photons entangled in the orbital angular momentum. We also show the experimental bounds of a possible cheater and the ways of detecting him.

  13. Measurement device-independent quantum dialogue

    NASA Astrophysics Data System (ADS)

    Maitra, Arpita

    2017-12-01

    Very recently, the experimental demonstration of quantum secure direct communication (QSDC) with state-of-the-art atomic quantum memory has been reported (Zhang et al. in Phys Rev Lett 118:220501, 2017). Quantum dialogue (QD) falls under QSDC where the secrete messages are communicated simultaneously between two legitimate parties. The successful experimental demonstration of QSDC opens up the possibilities for practical implementation of QD protocols. Thus, it is necessary to analyze the practical security issues of QD protocols for future implementation. Since the very first proposal for QD by Nguyen (Phys Lett A 328:6-10, 2004), a large number of variants and extensions have been presented till date. However, all of those leak half of the secret bits to the adversary through classical communications of the measurement results. In this direction, motivated by the idea of Lo et al. (Phys Rev Lett 108:130503, 2012), we propose a measurement device-independent quantum dialogue scheme which is resistant to such information leakage as well as side-channel attacks. In the proposed protocol, Alice and Bob, two legitimate parties, are allowed to prepare the states only. The states are measured by an untrusted third party who may himself behave as an adversary. We show that our protocol is secure under this adversarial model. The current protocol does not require any quantum memory, and thus, it is inherently robust against memory attacks. Such robustness might not be guaranteed in the QSDC protocol with quantum memory (Zhang et al. 2017).

  14. Quantum gambling using mesoscopic ring qubits

    NASA Astrophysics Data System (ADS)

    Pakuła, Ireneusz

    2007-07-01

    Quantum Game Theory provides us with new tools for practising games and some other risk related enterprices like, for example, gambling. The two party gambling protocol presented by Goldenberg {\\it et al} is one of the simplest yet still hard to implement applications of Quantum Game Theory. We propose potential physical realisation of the quantum gambling protocol with use of three mesoscopic ring qubits. We point out problems in implementation of such game.

  15. Device-independent two-party cryptography secure against sequential attacks

    NASA Astrophysics Data System (ADS)

    Kaniewski, Jędrzej; Wehner, Stephanie

    2016-05-01

    The goal of two-party cryptography is to enable two parties, Alice and Bob, to solve common tasks without the need for mutual trust. Examples of such tasks are private access to a database, and secure identification. Quantum communication enables security for all of these problems in the noisy-storage model by sending more signals than the adversary can store in a certain time frame. Here, we initiate the study of device-independent (DI) protocols for two-party cryptography in the noisy-storage model. Specifically, we present a relatively easy to implement protocol for a cryptographic building block known as weak string erasure and prove its security even if the devices used in the protocol are prepared by the dishonest party. DI two-party cryptography is made challenging by the fact that Alice and Bob do not trust each other, which requires new techniques to establish security. We fully analyse the case of memoryless devices (for which sequential attacks are optimal) and the case of sequential attacks for arbitrary devices. The key ingredient of the proof, which might be of independent interest, is an explicit (and tight) relation between the violation of the Clauser-Horne-Shimony-Holt inequality observed by Alice and Bob and uncertainty generated by Alice against Bob who is forced to measure his system before finding out Alice’s setting (guessing with postmeasurement information). In particular, we show that security is possible for arbitrarily small violation.

  16. Implementation of bipartite or remote unitary gates with repeater nodes

    NASA Astrophysics Data System (ADS)

    Yu, Li; Nemoto, Kae

    2016-08-01

    We propose some protocols to implement various classes of bipartite unitary operations on two remote parties with the help of repeater nodes in-between. We also present a protocol to implement a single-qubit unitary with parameters determined by a remote party with the help of up to three repeater nodes. It is assumed that the neighboring nodes are connected by noisy photonic channels, and the local gates can be performed quite accurately, while the decoherence of memories is significant. A unitary is often a part of a larger computation or communication task in a quantum network, and to reduce the amount of decoherence in other systems of the network, we focus on the goal of saving the total time for implementing a unitary including the time for entanglement preparation. We review some previously studied protocols that implement bipartite unitaries using local operations and classical communication and prior shared entanglement, and apply them to the situation with repeater nodes without prior entanglement. We find that the protocols using piecewise entanglement between neighboring nodes often require less total time compared to preparing entanglement between the two end nodes first and then performing the previously known protocols. For a generic bipartite unitary, as the number of repeater nodes increases, the total time could approach the time cost for direct signal transfer from one end node to the other. We also prove some lower bounds of the total time when there are a small number of repeater nodes. The application to position-based cryptography is discussed.

  17. Measurement-device-independent quantum key distribution for Scarani-Acin-Ribordy-Gisin 04 protocol

    PubMed Central

    Mizutani, Akihiro; Tamaki, Kiyoshi; Ikuta, Rikizo; Yamamoto, Takashi; Imoto, Nobuyuki

    2014-01-01

    The measurement-device-independent quantum key distribution (MDI QKD) was proposed to make BB84 completely free from any side-channel in detectors. Like in prepare & measure QKD, the use of other protocols in MDI setting would be advantageous in some practical situations. In this paper, we consider SARG04 protocol in MDI setting. The prepare & measure SARG04 is proven to be able to generate a key up to two-photon emission events. In MDI setting we show that the key generation is possible from the event with single or two-photon emission by a party and single-photon emission by the other party, but the two-photon emission event by both parties cannot contribute to the key generation. On the contrary to prepare & measure SARG04 protocol where the experimental setup is exactly the same as BB84, the measurement setup for SARG04 in MDI setting cannot be the same as that for BB84 since the measurement setup for BB84 in MDI setting induces too many bit errors. To overcome this problem, we propose two alternative experimental setups, and we simulate the resulting key rate. Our study highlights the requirements that MDI QKD poses on us regarding with the implementation of a variety of QKD protocols. PMID:24913431

  18. Secure multi-party quantum summation based on quantum Fourier transform

    NASA Astrophysics Data System (ADS)

    Yang, Hui-Yi; Ye, Tian-Yu

    2018-06-01

    In this paper, we propose a novel secure multi-party quantum summation protocol based on quantum Fourier transform, where the traveling particles are transmitted in a tree-type mode. The party who prepares the initial quantum states is assumed to be semi-honest, which means that she may misbehave on her own but will not conspire with anyone. The proposed protocol can resist both the outside attacks and the participant attacks. Especially, one party cannot obtain other parties' private integer strings; and it is secure for the colluding attack performed by at most n - 2 parties, where n is the number of parties. In addition, the proposed protocol calculates the addition of modulo d and implements the calculation of addition in a secret-by-secret way rather than a bit-by-bit way.

  19. A novel quantum solution to secure two-party distance computation

    NASA Astrophysics Data System (ADS)

    Peng, Zhen-wan; Shi, Run-hua; Wang, Pan-hong; Zhang, Shun

    2018-06-01

    Secure Two-Party Distance Computation is an important primitive of Secure Multiparty Computational Geometry that it involves two parties, where each party has a private point, and the two parties want to jointly compute the distance between their points without revealing anything about their respective private information. Secure Two-Party Distance Computation has very important and potential applications in settings of high secure requirements, such as privacy-preserving Determination of Spatial Location-Relation, Determination of Polygons Similarity, and so on. In this paper, we present a quantum protocol for Secure Two-Party Distance Computation by using QKD-based Quantum Private Query. The security of the protocol is based on the physical principles of quantum mechanics, instead of difficulty assumptions, and therefore, it can ensure higher security than the classical related protocols.

  20. Practical secure quantum communications

    NASA Astrophysics Data System (ADS)

    Diamanti, Eleni

    2015-05-01

    We review recent advances in the field of quantum cryptography, focusing in particular on practical implementations of two central protocols for quantum network applications, namely key distribution and coin flipping. The former allows two parties to share secret messages with information-theoretic security, even in the presence of a malicious eavesdropper in the communication channel, which is impossible with classical resources alone. The latter enables two distrustful parties to agree on a random bit, again with information-theoretic security, and with a cheating probability lower than the one that can be reached in a classical scenario. Our implementations rely on continuous-variable technology for quantum key distribution and on a plug and play discrete-variable system for coin flipping, and necessitate a rigorous security analysis adapted to the experimental schemes and their imperfections. In both cases, we demonstrate the protocols with provable security over record long distances in optical fibers and assess the performance of our systems as well as their limitations. The reported advances offer a powerful toolbox for practical applications of secure communications within future quantum networks.

  1. Implementing Diffie-Hellman key exchange using quantum EPR pairs

    NASA Astrophysics Data System (ADS)

    Mandal, Sayonnha; Parakh, Abhishek

    2015-05-01

    This paper implements the concepts of perfect forward secrecy and the Diffie-Hellman key exchange using EPR pairs to establish and share a secret key between two non-authenticated parties and transfer messages between them without the risk of compromise. Current implementations of quantum cryptography are based on the BB84 protocol, which is susceptible to siphoning attacks on the multiple photons emitted by practical laser sources. This makes BB84-based quantum cryptography protocol unsuitable for network computing environments. Diffie-Hellman does not require the two parties to be mutually authenticated to each other, yet it can provide a basis for a number of authenticated protocols, most notably the concept of perfect forward secrecy. The work proposed in this paper provides a new direction in utilizing quantum EPR pairs in quantum key exchange. Although, classical cryptography boasts of efficient and robust protocols like the Diffie-Hellman key exchange, in the current times, with the advent of quantum computing they are very much vulnerable to eavesdropping and cryptanalytic attacks. Using quantum cryptographic principles, however, these classical encryption algorithms show more promise and a more robust and secure structure for applications. The unique properties of quantum EPR pairs also, on the other hand, go a long way in removing attacks like eavesdropping by their inherent nature of one particle of the pair losing its state if a measurement occurs on the other. The concept of perfect forward secrecy is revisited in this paper to attribute tighter security to the proposed protocol.

  2. Relating quantum privacy and quantum coherence: an operational approach.

    PubMed

    Devetak, I; Winter, A

    2004-08-20

    Given many realizations of a state or a channel as a resource, two parties can generate a secret key as well as entanglement. We describe protocols to perform the secret key distillation (as it turns out, with optimal rate). Then we show how to achieve optimal entanglement generation rates by "coherent" implementation of a class of secret key agreement protocols, proving the long-conjectured "hashing inequality."

  3. Password-only authenticated three-party key exchange proven secure against insider dictionary attacks.

    PubMed

    Nam, Junghyun; Choo, Kim-Kwang Raymond; Paik, Juryon; Won, Dongho

    2014-01-01

    While a number of protocols for password-only authenticated key exchange (PAKE) in the 3-party setting have been proposed, it still remains a challenging task to prove the security of a 3-party PAKE protocol against insider dictionary attacks. To the best of our knowledge, there is no 3-party PAKE protocol that carries a formal proof, or even definition, of security against insider dictionary attacks. In this paper, we present the first 3-party PAKE protocol proven secure against both online and offline dictionary attacks as well as insider and outsider dictionary attacks. Our construct can be viewed as a protocol compiler that transforms any 2-party PAKE protocol into a 3-party PAKE protocol with 2 additional rounds of communication. We also present a simple and intuitive approach of formally modelling dictionary attacks in the password-only 3-party setting, which significantly reduces the complexity of proving the security of 3-party PAKE protocols against dictionary attacks. In addition, we investigate the security of the well-known 3-party PAKE protocol, called GPAKE, due to Abdalla et al. (2005, 2006), and demonstrate that the security of GPAKE against online dictionary attacks depends heavily on the composition of its two building blocks, namely a 2-party PAKE protocol and a 3-party key distribution protocol.

  4. Two-party quantum key agreement protocols under collective noise channel

    NASA Astrophysics Data System (ADS)

    Gao, Hao; Chen, Xiao-Guang; Qian, Song-Rong

    2018-06-01

    Recently, quantum communication has become a very popular research field. The quantum key agreement (QKA) plays an important role in the field of quantum communication, based on its unconditional security in terms of theory. Among all kinds of QKA protocols, QKA protocols resisting collective noise are widely being studied. In this paper, we propose improved two-party QKA protocols resisting collective noise and present a feasible plan for information reconciliation. Our protocols' qubit efficiency has achieved 26.67%, which is the best among all the two-party QKA protocols against collective noise, thus showing that our protocol can improve the transmission efficiency of quantum key agreement.

  5. Policy-Based Negotiation Engine for Cross-Domain Interoperability

    NASA Technical Reports Server (NTRS)

    Vatan, Farrokh; Chow, Edward T.

    2012-01-01

    A successful policy negotiation scheme for Policy-Based Management (PBM) has been implemented. Policy negotiation is the process of determining the "best" communication policy that all of the parties involved can agree on. Specifically, the problem is how to reconcile the various (and possibly conflicting) communication protocols used by different divisions. The solution must use protocols available to all parties involved, and should attempt to do so in the best way possible. Which protocols are commonly available, and what the definition of "best" is will be dependent on the parties involved and their individual communications priorities.

  6. Password-Only Authenticated Three-Party Key Exchange Proven Secure against Insider Dictionary Attacks

    PubMed Central

    Nam, Junghyun; Choo, Kim-Kwang Raymond

    2014-01-01

    While a number of protocols for password-only authenticated key exchange (PAKE) in the 3-party setting have been proposed, it still remains a challenging task to prove the security of a 3-party PAKE protocol against insider dictionary attacks. To the best of our knowledge, there is no 3-party PAKE protocol that carries a formal proof, or even definition, of security against insider dictionary attacks. In this paper, we present the first 3-party PAKE protocol proven secure against both online and offline dictionary attacks as well as insider and outsider dictionary attacks. Our construct can be viewed as a protocol compiler that transforms any 2-party PAKE protocol into a 3-party PAKE protocol with 2 additional rounds of communication. We also present a simple and intuitive approach of formally modelling dictionary attacks in the password-only 3-party setting, which significantly reduces the complexity of proving the security of 3-party PAKE protocols against dictionary attacks. In addition, we investigate the security of the well-known 3-party PAKE protocol, called GPAKE, due to Abdalla et al. (2005, 2006), and demonstrate that the security of GPAKE against online dictionary attacks depends heavily on the composition of its two building blocks, namely a 2-party PAKE protocol and a 3-party key distribution protocol. PMID:25309956

  7. Multi-Party Quantum Private Comparison Protocol Based on Entanglement Swapping of Bell Entangled States

    NASA Astrophysics Data System (ADS)

    Ye, Tian-Yu

    2016-09-01

    Recently, Liu et al. proposed a two-party quantum private comparison (QPC) protocol using entanglement swapping of Bell entangled state (Commun. Theor. Phys. 57 (2012) 583). Subsequently Liu et al. pointed out that in Liu et al.'s protocol, the TP can extract the two users' secret inputs without being detected by launching the Bell-basis measurement attack, and suggested the corresponding improvement to mend this loophole (Commun. Theor. Phys. 62 (2014) 210). In this paper, we first point out the information leakage problem toward TP existing in both of the above two protocols, and then suggest the corresponding improvement by using the one-way hash function to encrypt the two users' secret inputs. We further put forward the three-party QPC protocol also based on entanglement swapping of Bell entangled state, and then validate its output correctness and its security in detail. Finally, we generalize the three-party QPC protocol into the multi-party case, which can accomplish arbitrary pair's comparison of equality among K users within one execution. Supported by the National Natural Science Foundation of China under Grant No. 61402407

  8. Clean Quantum and Classical Communication Protocols.

    PubMed

    Buhrman, Harry; Christandl, Matthias; Perry, Christopher; Zuiddam, Jeroen

    2016-12-02

    By how much must the communication complexity of a function increase if we demand that the parties not only correctly compute the function but also return all registers (other than the one containing the answer) to their initial states at the end of the communication protocol? Protocols that achieve this are referred to as clean and the associated cost as the clean communication complexity. Here we present clean protocols for calculating the inner product of two n-bit strings, showing that (in the absence of preshared entanglement) at most n+3 qubits or n+O(sqrt[n]) bits of communication are required. The quantum protocol provides inspiration for obtaining the optimal method to implement distributed cnot gates in parallel while minimizing the amount of quantum communication. For more general functions, we show that nearly all Boolean functions require close to 2n bits of classical communication to compute and close to n qubits if the parties have access to preshared entanglement. Both of these values are maximal for their respective paradigms.

  9. Entangled state quantum cryptography: eavesdropping on the ekert protocol

    PubMed

    Naik; Peterson; White; Berglund; Kwiat

    2000-05-15

    Using polarization-entangled photons from spontaneous parametric down-conversion, we have implemented Ekert's quantum cryptography protocol. The near-perfect correlations of the photons allow the sharing of a secret key between two parties. The presence of an eavesdropper is continually checked by measuring Bell's inequalities. We investigated several possible eavesdropper strategies, including pseudo-quantum-nondemolition measurements. In all cases, the eavesdropper's presence was readily apparent. We discuss a procedure to increase her detectability.

  10. A Generalized Model of E-trading for GSR Fair Exchange Protocol

    NASA Astrophysics Data System (ADS)

    Konar, Debajyoti; Mazumdar, Chandan

    In this paper we propose a generalized model of E-trading for the development of GSR Fair Exchange Protocols. Based on the model, a method is narrated to implement E-trading protocols that ensure fairness in true sense without using an additional trusted third party for which either party has to pay. The model provides the scope to include the correctness of the product, money atomicity and customer's anonymity properties within E-trading protocol. We conclude this paper by indicating the area of applicability for our model.

  11. 24-Hour Relativistic Bit Commitment.

    PubMed

    Verbanis, Ephanielle; Martin, Anthony; Houlmann, Raphaël; Boso, Gianluca; Bussières, Félix; Zbinden, Hugo

    2016-09-30

    Bit commitment is a fundamental cryptographic primitive in which a party wishes to commit a secret bit to another party. Perfect security between mistrustful parties is unfortunately impossible to achieve through the asynchronous exchange of classical and quantum messages. Perfect security can nonetheless be achieved if each party splits into two agents exchanging classical information at times and locations satisfying strict relativistic constraints. A relativistic multiround protocol to achieve this was previously proposed and used to implement a 2-millisecond commitment time. Much longer durations were initially thought to be insecure, but recent theoretical progress showed that this is not so. In this Letter, we report on the implementation of a 24-hour bit commitment solely based on timed high-speed optical communication and fast data processing, with all agents located within the city of Geneva. This duration is more than 6 orders of magnitude longer than before, and we argue that it could be extended to one year and allow much more flexibility on the locations of the agents. Our implementation offers a practical and viable solution for use in applications such as digital signatures, secure voting and honesty-preserving auctions.

  12. Secured Communication for Business Process Outsourcing Using Optimized Arithmetic Cryptography Protocol Based on Virtual Parties

    NASA Astrophysics Data System (ADS)

    Pathak, Rohit; Joshi, Satyadhar

    Within a span of over a decade, India has become one of the most favored destinations across the world for Business Process Outsourcing (BPO) operations. India has rapidly achieved the status of being the most preferred destination for BPO for companies located in the US and Europe. Security and privacy are the two major issues needed to be addressed by the Indian software industry to have an increased and long-term outsourcing contract from the US. Another important issue is about sharing employee’s information to ensure that data and vital information of an outsourcing company is secured and protected. To ensure that the confidentiality of a client’s information is maintained, BPOs need to implement some data security measures. In this paper, we propose a new protocol for specifically for BPO Secure Multi-Party Computation (SMC). As there are many computations and surveys which involve confidential data from many parties or organizations and the concerned data is property of the organization, preservation and security of this data is of prime importance for such type of computations. Although the computation requires data from all the parties, but none of the associated parties would want to reveal their data to the other parties. We have proposed a new efficient and scalable protocol to perform computation on encrypted information. The information is encrypted in a manner that it does not affect the result of the computation. It uses modifier tokens which are distributed among virtual parties, and finally used in the computation. The computation function uses the acquired data and modifier tokens to compute right result from the encrypted data. Thus without revealing the data, right result can be computed and privacy of the parties is maintained. We have given a probabilistic security analysis of hacking the protocol and shown how zero hacking security can be achieved. Also we have analyzed the specific case of Indian BPO.

  13. Bidirectional Controlled Joint Remote State Preparation via a Seven-Qubit Entangled State

    NASA Astrophysics Data System (ADS)

    Wang, Xiao-yu; Mo, Zhi-wen

    2017-04-01

    A new protocol for implementing five-party bidirectional controlled joint remote state preparation is proposed by using a seven-qubit entangled state as the quantum channel. It can be shown that two distant senders can simultaneously and deterministically exchange their states with the other senders under the control of the supervisor, and it cannot be succeed without permission of the controller. Only pauli operation and single-qubit measurement are used in our scheme, so the scheme with five-party is feasible within the reach of current technologies.

  14. Entangled State Quantum Cryptography: Eavesdropping on the Ekert Protocol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Naik, D. S.; Peterson, C. G.; White, A. G.

    2000-05-15

    Using polarization-entangled photons from spontaneous parametric down-conversion, we have implemented Ekert's quantum cryptography protocol. The near-perfect correlations of the photons allow the sharing of a secret key between two parties. The presence of an eavesdropper is continually checked by measuring Bell's inequalities. We investigated several possible eavesdropper strategies, including pseudo-quantum-nondemolition measurements. In all cases, the eavesdropper's presence was readily apparent. We discuss a procedure to increase her detectability. (c) 2000 The American Physical Society.

  15. Deterministic and efficient quantum cryptography based on Bell's theorem

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen Zengbing; Pan Jianwei; Physikalisches Institut, Universitaet Heidelberg, Philosophenweg 12, 69120 Heidelberg

    2006-05-15

    We propose a double-entanglement-based quantum cryptography protocol that is both efficient and deterministic. The proposal uses photon pairs with entanglement both in polarization and in time degrees of freedom; each measurement in which both of the two communicating parties register a photon can establish one and only one perfect correlation, and thus deterministically create a key bit. Eavesdropping can be detected by violation of local realism. A variation of the protocol shows a higher security, similar to the six-state protocol, under individual attacks. Our scheme allows a robust implementation under the current technology.

  16. A novel quantum scheme for secure two-party distance computation

    NASA Astrophysics Data System (ADS)

    Peng, Zhen-wan; Shi, Run-hua; Zhong, Hong; Cui, Jie; Zhang, Shun

    2017-12-01

    Secure multiparty computational geometry is an essential field of secure multiparty computation, which computes a computation geometric problem without revealing any private information of each party. Secure two-party distance computation is a primitive of secure multiparty computational geometry, which computes the distance between two points without revealing each point's location information (i.e., coordinate). Secure two-party distance computation has potential applications with high secure requirements in military, business, engineering and so on. In this paper, we present a quantum solution to secure two-party distance computation by subtly using quantum private query. Compared to the classical related protocols, our quantum protocol can ensure higher security and better privacy protection because of the physical principle of quantum mechanics.

  17. Quantum Gambling

    NASA Astrophysics Data System (ADS)

    Goldenberg, Lior; Vaidman, Lev; Wiesner, Stephen

    1999-04-01

    We present a two-party protocol for ``quantum gambling,'' a new task closely related to coin tossing. The protocol allows two remote parties to play a gambling game such that in a certain limit it becomes a fair game. No unconditionally secure classical method is known to accomplish this task.

  18. Three-party quantum secure direct communication against collective noise

    NASA Astrophysics Data System (ADS)

    He, Ye-Feng; Ma, Wen-Ping

    2017-10-01

    Based on logical quantum states, two three-party quantum secure direct communication protocols are proposed, which can realize the exchange of the secret messages between three parties with the help of the measurement correlation property of six-particle entangled states. These two protocols can be immune to the collective-dephasing noise and the collective-rotation noise, respectively; neither of them has information leakage problem. The one-way transmission mode ensures that they can congenitally resist against the Trojan horse attacks and the teleportation attack. Furthermore, these two protocols are secure against other active attacks because of the use of the decoy state technology.

  19. Two Quantum Protocols for Oblivious Set-member Decision Problem

    NASA Astrophysics Data System (ADS)

    Shi, Run-Hua; Mu, Yi; Zhong, Hong; Cui, Jie; Zhang, Shun

    2015-10-01

    In this paper, we defined a new secure multi-party computation problem, called Oblivious Set-member Decision problem, which allows one party to decide whether a secret of another party belongs to his private set in an oblivious manner. There are lots of important applications of Oblivious Set-member Decision problem in fields of the multi-party collaborative computation of protecting the privacy of the users, such as private set intersection and union, anonymous authentication, electronic voting and electronic auction. Furthermore, we presented two quantum protocols to solve the Oblivious Set-member Decision problem. Protocol I takes advantage of powerful quantum oracle operations so that it needs lower costs in both communication and computation complexity; while Protocol II takes photons as quantum resources and only performs simple single-particle projective measurements, thus it is more feasible with the present technology.

  20. Two Quantum Protocols for Oblivious Set-member Decision Problem

    PubMed Central

    Shi, Run-hua; Mu, Yi; Zhong, Hong; Cui, Jie; Zhang, Shun

    2015-01-01

    In this paper, we defined a new secure multi-party computation problem, called Oblivious Set-member Decision problem, which allows one party to decide whether a secret of another party belongs to his private set in an oblivious manner. There are lots of important applications of Oblivious Set-member Decision problem in fields of the multi-party collaborative computation of protecting the privacy of the users, such as private set intersection and union, anonymous authentication, electronic voting and electronic auction. Furthermore, we presented two quantum protocols to solve the Oblivious Set-member Decision problem. Protocol I takes advantage of powerful quantum oracle operations so that it needs lower costs in both communication and computation complexity; while Protocol II takes photons as quantum resources and only performs simple single-particle projective measurements, thus it is more feasible with the present technology. PMID:26514668

  1. Two Quantum Protocols for Oblivious Set-member Decision Problem.

    PubMed

    Shi, Run-Hua; Mu, Yi; Zhong, Hong; Cui, Jie; Zhang, Shun

    2015-10-30

    In this paper, we defined a new secure multi-party computation problem, called Oblivious Set-member Decision problem, which allows one party to decide whether a secret of another party belongs to his private set in an oblivious manner. There are lots of important applications of Oblivious Set-member Decision problem in fields of the multi-party collaborative computation of protecting the privacy of the users, such as private set intersection and union, anonymous authentication, electronic voting and electronic auction. Furthermore, we presented two quantum protocols to solve the Oblivious Set-member Decision problem. Protocol I takes advantage of powerful quantum oracle operations so that it needs lower costs in both communication and computation complexity; while Protocol II takes photons as quantum resources and only performs simple single-particle projective measurements, thus it is more feasible with the present technology.

  2. Controlled mutual quantum entity authentication with an untrusted third party

    NASA Astrophysics Data System (ADS)

    Kang, Min-Sung; Heo, Jino; Hong, Chang-Ho; Yang, Hyung-Jin; Han, Sang-Wook; Moon, Sung

    2018-07-01

    We propose a quantum control entity mutual authentication protocol that can be executed in environments involving an untrusted third party. In general, the third party, referred to as Charlie, can be an entity such as a telephone company, server, financial company, or login webpage for a portal service. Most communication protocols controlled by third parties are vulnerable to internal attacks. In this study, we present two solutions that make use of an entanglement correlation checking method and random numbers against an internal attack by an untrusted third party.

  3. Three-party Quantum Secure Direct Communication with Single Photons in both Polarization and Spatial-mode Degrees of Freedom

    NASA Astrophysics Data System (ADS)

    Wang, LiLi; Ma, WenPing; Wang, MeiLing; Shen, DongSu

    2016-05-01

    We present an efficient three-party quantum secure direct communication (QSDC) protocol with single photos in both polarization and spatial-mode degrees of freedom. The three legal parties' messages can be encoded on the polarization and the spatial-mode states of single photons independently with desired unitary operations. A party can obtain the other two parties' messages simultaneously through a quantum channel. Because no extra public information is transmitted in the classical channels, the drawback of information leakage or classical correlation does not exist in the proposed scheme. Moreover, the comprehensive security analysis shows that the presented QSDC network protocol can defend the outsider eavesdropper's several sorts of attacks. Compared with the single photons with only one degree of freedom, our protocol based on the single photons in two degrees of freedom has higher capacity. Since the preparation and the measurement of single photon quantum states in both the polarization and the spatial-mode degrees of freedom are available with current quantum techniques, the proposed protocol is practical.

  4. Fully device-independent conference key agreement

    NASA Astrophysics Data System (ADS)

    Ribeiro, Jérémy; Murta, Gláucia; Wehner, Stephanie

    2018-02-01

    We present a security analysis of conference key agreement (CKA) in the most adversarial model of device independence (DI). Our protocol can be implemented by any experimental setup that is capable of performing Bell tests [specifically, the Mermin-Ardehali-Belinskii-Klyshko (MABK) inequality], and security can in principle be obtained for any violation of the MABK inequality that detects genuine multipartite entanglement among the N parties involved in the protocol. As our main tool, we derive a direct physical connection between the N -partite MABK inequality and the Clauser-Horne-Shimony-Holt (CHSH) inequality, showing that certain violations of the MABK inequality correspond to a violation of the CHSH inequality between one of the parties and the other N -1 . We compare the asymptotic key rate for device-independent conference key agreement (DICKA) to the case where the parties use N -1 device-independent quantum key distribution protocols in order to generate a common key. We show that for some regime of noise the DICKA protocol leads to better rates.

  5. Two-party quantum key agreement with five-particle entangled states

    NASA Astrophysics Data System (ADS)

    He, Ye-Feng; Ma, Wen-Ping

    A two-party quantum key agreement protocol is proposed with five-particle entangled states and the delayed measurement technique. According to the measurement correlation property of five-particle entangled states, two participants can deduce the measurement results of each other’s initial quantum states. As a result, two parties can extract the secret keys of each other by using the publicly announced value or by performing the delayed measurement, respectively. Thus, a shared key is fairly established. Since each particle is transmitted only once in quantum channel, the protocol is congenitally free from the Trojan horse attacks. It is shown that the protocol not only is secure against both participant and outsider attacks but also has no information leakage problem. Moreover, it has high qubit efficiency.

  6. Experimental plug and play quantum coin flipping.

    PubMed

    Pappa, Anna; Jouguet, Paul; Lawson, Thomas; Chailloux, André; Legré, Matthieu; Trinkler, Patrick; Kerenidis, Iordanis; Diamanti, Eleni

    2014-04-24

    Performing complex cryptographic tasks will be an essential element in future quantum communication networks. These tasks are based on a handful of fundamental primitives, such as coin flipping, where two distrustful parties wish to agree on a randomly generated bit. Although it is known that quantum versions of these primitives can offer information-theoretic security advantages with respect to classical protocols, a demonstration of such an advantage in a practical communication scenario has remained elusive. Here we experimentally implement a quantum coin flipping protocol that performs strictly better than classically possible over a distance suitable for communication over metropolitan area optical networks. The implementation is based on a practical plug and play system, developed by significantly enhancing a commercial quantum key distribution device. Moreover, we provide combined quantum coin flipping protocols that are almost perfectly secure against bounded adversaries. Our results offer a useful toolbox for future secure quantum communications.

  7. Clauser-Horne-Shimony-Holt versus three-party pseudo-telepathy: on the optimal number of samples in device-independent quantum private query

    NASA Astrophysics Data System (ADS)

    Basak, Jyotirmoy; Maitra, Subhamoy

    2018-04-01

    In device-independent (DI) paradigm, the trustful assumptions over the devices are removed and CHSH test is performed to check the functionality of the devices toward certifying the security of the protocol. The existing DI protocols consider infinite number of samples from theoretical point of view, though this is not practically implementable. For finite sample analysis of the existing DI protocols, we may also consider strategies for checking device independence other than the CHSH test. In this direction, here we present a comparative analysis between CHSH and three-party Pseudo-telepathy game for the quantum private query protocol in DI paradigm that appeared in Maitra et al. (Phys Rev A 95:042344, 2017) very recently.

  8. Complete Insecurity of Quantum Protocols for Classical Two-Party Computation

    NASA Astrophysics Data System (ADS)

    Buhrman, Harry; Christandl, Matthias; Schaffner, Christian

    2012-10-01

    A fundamental task in modern cryptography is the joint computation of a function which has two inputs, one from Alice and one from Bob, such that neither of the two can learn more about the other’s input than what is implied by the value of the function. In this Letter, we show that any quantum protocol for the computation of a classical deterministic function that outputs the result to both parties (two-sided computation) and that is secure against a cheating Bob can be completely broken by a cheating Alice. Whereas it is known that quantum protocols for this task cannot be completely secure, our result implies that security for one party implies complete insecurity for the other. Our findings stand in stark contrast to recent protocols for weak coin tossing and highlight the limits of cryptography within quantum mechanics. We remark that our conclusions remain valid, even if security is only required to be approximate and if the function that is computed for Bob is different from that of Alice.

  9. Complete insecurity of quantum protocols for classical two-party computation.

    PubMed

    Buhrman, Harry; Christandl, Matthias; Schaffner, Christian

    2012-10-19

    A fundamental task in modern cryptography is the joint computation of a function which has two inputs, one from Alice and one from Bob, such that neither of the two can learn more about the other's input than what is implied by the value of the function. In this Letter, we show that any quantum protocol for the computation of a classical deterministic function that outputs the result to both parties (two-sided computation) and that is secure against a cheating Bob can be completely broken by a cheating Alice. Whereas it is known that quantum protocols for this task cannot be completely secure, our result implies that security for one party implies complete insecurity for the other. Our findings stand in stark contrast to recent protocols for weak coin tossing and highlight the limits of cryptography within quantum mechanics. We remark that our conclusions remain valid, even if security is only required to be approximate and if the function that is computed for Bob is different from that of Alice.

  10. Application of Blind Quantum Computation to Two-Party Quantum Computation

    NASA Astrophysics Data System (ADS)

    Sun, Zhiyuan; Li, Qin; Yu, Fang; Chan, Wai Hong

    2018-06-01

    Blind quantum computation (BQC) allows a client who has only limited quantum power to achieve quantum computation with the help of a remote quantum server and still keep the client's input, output, and algorithm private. Recently, Kashefi and Wallden extended BQC to achieve two-party quantum computation which allows two parties Alice and Bob to perform a joint unitary transform upon their inputs. However, in their protocol Alice has to prepare rotated single qubits and perform Pauli operations, and Bob needs to have a powerful quantum computer. In this work, we also utilize the idea of BQC to put forward an improved two-party quantum computation protocol in which the operations of both Alice and Bob are simplified since Alice only needs to apply Pauli operations and Bob is just required to prepare and encrypt his input qubits.

  11. Application of Blind Quantum Computation to Two-Party Quantum Computation

    NASA Astrophysics Data System (ADS)

    Sun, Zhiyuan; Li, Qin; Yu, Fang; Chan, Wai Hong

    2018-03-01

    Blind quantum computation (BQC) allows a client who has only limited quantum power to achieve quantum computation with the help of a remote quantum server and still keep the client's input, output, and algorithm private. Recently, Kashefi and Wallden extended BQC to achieve two-party quantum computation which allows two parties Alice and Bob to perform a joint unitary transform upon their inputs. However, in their protocol Alice has to prepare rotated single qubits and perform Pauli operations, and Bob needs to have a powerful quantum computer. In this work, we also utilize the idea of BQC to put forward an improved two-party quantum computation protocol in which the operations of both Alice and Bob are simplified since Alice only needs to apply Pauli operations and Bob is just required to prepare and encrypt his input qubits.

  12. Counterfactual attack on counterfactual quantum key distribution

    NASA Astrophysics Data System (ADS)

    Zhang, Sheng; Wnang, Jian; Tang, Chao Jing

    2012-05-01

    It is interesting that counterfactual quantum cryptography protocols allow two remotely separated parties to share a secret key without transmitting any signal particles. Generally, these protocols, expected to provide security advantages, base their security on a translated no-cloning theorem. Therefore, they potentially exhibit unconditional security in theory. In this letter, we propose a new Trojan horse attack, by which an eavesdropper Eve can gain full information about the key without being noticed, to real implementations of a counterfactual quantum cryptography system. Most importantly, the presented attack is available even if the system has negligible imperfections. Therefore, it shows that the present realization of counterfactual quantum key distribution is vulnerable.

  13. Password-only authenticated three-party key exchange with provable security in the standard model.

    PubMed

    Nam, Junghyun; Choo, Kim-Kwang Raymond; Kim, Junghwan; Kang, Hyun-Kyu; Kim, Jinsoo; Paik, Juryon; Won, Dongho

    2014-01-01

    Protocols for password-only authenticated key exchange (PAKE) in the three-party setting allow two clients registered with the same authentication server to derive a common secret key from their individual password shared with the server. Existing three-party PAKE protocols were proven secure under the assumption of the existence of random oracles or in a model that does not consider insider attacks. Therefore, these protocols may turn out to be insecure when the random oracle is instantiated with a particular hash function or an insider attack is mounted against the partner client. The contribution of this paper is to present the first three-party PAKE protocol whose security is proven without any idealized assumptions in a model that captures insider attacks. The proof model we use is a variant of the indistinguishability-based model of Bellare, Pointcheval, and Rogaway (2000), which is one of the most widely accepted models for security analysis of password-based key exchange protocols. We demonstrated that our protocol achieves not only the typical indistinguishability-based security of session keys but also the password security against undetectable online dictionary attacks.

  14. Quantum Dialogue with Authentication Based on Bell States

    NASA Astrophysics Data System (ADS)

    Shen, Dongsu; Ma, Wenping; Yin, Xunru; Li, Xiaoping

    2013-06-01

    We propose an authenticated quantum dialogue protocol, which is based on a shared private quantum entangled channel. In this protocol, the EPR pairs are randomly prepared in one of the four Bell states for communication. By performing four Pauli operations on the shared EPR pairs to encode their shared authentication key and secret message, two legitimate users can implement mutual identity authentication and quantum dialogue without the help from the third party authenticator. Furthermore, due to the EPR pairs which are used for secure communication are utilized to implement authentication and the whole authentication process is included in the direct secure communication process, it does not require additional particles to realize authentication in this protocol. The updated authentication key provides the counterparts with a new authentication key for the next authentication and direct communication. Compared with other secure communication with authentication protocols, this one is more secure and efficient owing to the combination of authentication and direct communication. Security analysis shows that it is secure against the eavesdropping attack, the impersonation attack and the man-in-the-middle (MITM) attack.

  15. Privacy-Preserving Integration of Medical Data : A Practical Multiparty Private Set Intersection.

    PubMed

    Miyaji, Atsuko; Nakasho, Kazuhisa; Nishida, Shohei

    2017-03-01

    Medical data are often maintained by different organizations. However, detailed analyses sometimes require these datasets to be integrated without violating patient or commercial privacy. Multiparty Private Set Intersection (MPSI), which is an important privacy-preserving protocol, computes an intersection of multiple private datasets. This approach ensures that only designated parties can identify the intersection. In this paper, we propose a practical MPSI that satisfies the following requirements: The size of the datasets maintained by the different parties is independent of the others, and the computational complexity of the dataset held by each party is independent of the number of parties. Our MPSI is based on the use of an outsourcing provider, who has no knowledge of the data inputs or outputs. This reduces the computational complexity. The performance of the proposed MPSI is evaluated by implementing a prototype on a virtual private network to enable parallel computation in multiple threads. Our protocol is confirmed to be more efficient than comparable existing approaches.

  16. Multi-party Measurement-Device-Independent Quantum Key Distribution Based on Cluster States

    NASA Astrophysics Data System (ADS)

    Liu, Chuanqi; Zhu, Changhua; Ma, Shuquan; Pei, Changxing

    2018-03-01

    We propose a novel multi-party measurement-device-independent quantum key distribution (MDI-QKD) protocol based on cluster states. A four-photon analyzer which can distinguish all the 16 cluster states serves as the measurement device for four-party MDI-QKD. Any two out of four participants can build secure keys after the analyzers obtains successful outputs and the two participants perform post-processing. We derive a security analysis for the protocol, and analyze the key rates under different values of polarization misalignment. The results show that four-party MDI-QKD is feasible over 280 km in the optical fiber channel when the key rate is about 10- 6 with the polarization misalignment parameter 0.015. Moreover, our work takes an important step toward a quantum communication network.

  17. Multi-party semi-quantum key distribution-convertible multi-party semi-quantum secret sharing

    NASA Astrophysics Data System (ADS)

    Yu, Kun-Fei; Gu, Jun; Hwang, Tzonelih; Gope, Prosanta

    2017-08-01

    This paper proposes a multi-party semi-quantum secret sharing (MSQSS) protocol which allows a quantum party (manager) to share a secret among several classical parties (agents) based on GHZ-like states. By utilizing the special properties of GHZ-like states, the proposed scheme can easily detect outside eavesdropping attacks and has the highest qubit efficiency among the existing MSQSS protocols. Then, we illustrate an efficient way to convert the proposed MSQSS protocol into a multi-party semi-quantum key distribution (MSQKD) protocol. The proposed approach is even useful to convert all the existing measure-resend type of semi-quantum secret sharing protocols into semi-quantum key distribution protocols.

  18. Deterministic secure quantum communication using a single d-level system.

    PubMed

    Jiang, Dong; Chen, Yuanyuan; Gu, Xuemei; Xie, Ling; Chen, Lijun

    2017-03-22

    Deterministic secure quantum communication (DSQC) can transmit secret messages between two parties without first generating a shared secret key. Compared with quantum key distribution (QKD), DSQC avoids the waste of qubits arising from basis reconciliation and thus reaches higher efficiency. In this paper, based on data block transmission and order rearrangement technologies, we propose a DSQC protocol. It utilizes a set of single d-level systems as message carriers, which are used to directly encode the secret message in one communication process. Theoretical analysis shows that these employed technologies guarantee the security, and the use of a higher dimensional quantum system makes our protocol achieve higher security and efficiency. Since only quantum memory is required for implementation, our protocol is feasible with current technologies. Furthermore, Trojan horse attack (THA) is taken into account in our protocol. We give a THA model and show that THA significantly increases the multi-photon rate and can thus be detected.

  19. Progress in satellite quantum key distribution

    NASA Astrophysics Data System (ADS)

    Bedington, Robert; Arrazola, Juan Miguel; Ling, Alexander

    2017-08-01

    Quantum key distribution (QKD) is a family of protocols for growing a private encryption key between two parties. Despite much progress, all ground-based QKD approaches have a distance limit due to atmospheric losses or in-fibre attenuation. These limitations make purely ground-based systems impractical for a global distribution network. However, the range of communication may be extended by employing satellites equipped with high-quality optical links. This manuscript summarizes research and development which is beginning to enable QKD with satellites. It includes a discussion of protocols, infrastructure, and the technical challenges involved with implementing such systems, as well as a top level summary of on-going satellite QKD initiatives around the world.

  20. Password-Only Authenticated Three-Party Key Exchange with Provable Security in the Standard Model

    PubMed Central

    Nam, Junghyun; Kim, Junghwan; Kang, Hyun-Kyu; Kim, Jinsoo; Paik, Juryon

    2014-01-01

    Protocols for password-only authenticated key exchange (PAKE) in the three-party setting allow two clients registered with the same authentication server to derive a common secret key from their individual password shared with the server. Existing three-party PAKE protocols were proven secure under the assumption of the existence of random oracles or in a model that does not consider insider attacks. Therefore, these protocols may turn out to be insecure when the random oracle is instantiated with a particular hash function or an insider attack is mounted against the partner client. The contribution of this paper is to present the first three-party PAKE protocol whose security is proven without any idealized assumptions in a model that captures insider attacks. The proof model we use is a variant of the indistinguishability-based model of Bellare, Pointcheval, and Rogaway (2000), which is one of the most widely accepted models for security analysis of password-based key exchange protocols. We demonstrated that our protocol achieves not only the typical indistinguishability-based security of session keys but also the password security against undetectable online dictionary attacks. PMID:24977229

  1. Chaotic maps and biometrics-based anonymous three-party authenticated key exchange protocol without using passwords

    NASA Astrophysics Data System (ADS)

    Xie, Qi; Hu, Bin; Chen, Ke-Fei; Liu, Wen-Hao; Tan, Xiao

    2015-11-01

    In three-party password authenticated key exchange (AKE) protocol, since two users use their passwords to establish a secure session key over an insecure communication channel with the help of the trusted server, such a protocol may suffer the password guessing attacks and the server has to maintain the password table. To eliminate the shortages of password-based AKE protocol, very recently, according to chaotic maps, Lee et al. [2015 Nonlinear Dyn. 79 2485] proposed a first three-party-authenticated key exchange scheme without using passwords, and claimed its security by providing a well-organized BAN logic test. Unfortunately, their protocol cannot resist impersonation attack, which is demonstrated in the present paper. To overcome their security weakness, by using chaotic maps, we propose a biometrics-based anonymous three-party AKE protocol with the same advantages. Further, we use the pi calculus-based formal verification tool ProVerif to show that our AKE protocol achieves authentication, security and anonymity, and an acceptable efficiency. Project supported by the Natural Science Foundation of Zhejiang Province, China (Grant No. LZ12F02005), the Major State Basic Research Development Program of China (Grant No. 2013CB834205), and the National Natural Science Foundation of China (Grant No. 61070153).

  2. Gaussian operations and privacy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Navascues, Miguel; Acin, Antonio

    2005-07-15

    We consider the possibilities offered by Gaussian states and operations for two honest parties, Alice and Bob, to obtain privacy against a third eavesdropping party, Eve. We first extend the security analysis of the protocol proposed in [Navascues et al. Phys. Rev. Lett. 94, 010502 (2005)]. Then, we prove that a generalized version of this protocol does not allow one to distill a secret key out of bound entangled Gaussian states.

  3. Entanglement-secured single-qubit quantum secret sharing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scherpelz, P.; Resch, R.; Berryrieser, D.

    In single-qubit quantum secret sharing, a secret is shared between N parties via manipulation and measurement of one qubit at a time. Each qubit is sent to all N parties in sequence; the secret is encoded in the first participant's preparation of the qubit state and the subsequent participants' choices of state rotation or measurement basis. We present a protocol for single-qubit quantum secret sharing using polarization entanglement of photon pairs produced in type-I spontaneous parametric downconversion. We investigate the protocol's security against eavesdropping attack under common experimental conditions: a lossy channel for photon transmission, and imperfect preparation of themore » initial qubit state. A protocol which exploits entanglement between photons, rather than simply polarization correlation, is more robustly secure. We implement the entanglement-based secret-sharing protocol with 87% secret-sharing fidelity, limited by the purity of the entangled state produced by our present apparatus. We demonstrate a photon-number splitting eavesdropping attack, which achieves no success against the entanglement-based protocol while showing the predicted rate of success against a correlation-based protocol.« less

  4. Tolerance - One Transplant for Life

    PubMed Central

    Kawai, Tatsuo; Leventhal, Joseph; Madsen, Joren C.; Strober, Samuel; Turka, Laurence A.; Wood, Kathryn J.

    2014-01-01

    A recent TTS workshop was convened to address the question: “What do we need to have in place to make tolerance induction protocols a “standard of care” for organ transplant recipients over the next decade?” In a productive two day meeting there was wide-ranging discussion on a broad series of topics resulting in five consensus recommendations: (1) Establish a registry of results for patients enrolled in tolerance trials; (2) Establish standardized protocols for sample collection and storage; (3) Establish standardized biomarkers and assays; (4) Include children aged 12 and older in protocols that have been validated in adults; (5) a task force to engage third party payers in discussions of how to fund tolerance trials. Future planned workshops will focus on progress in implementing these recommendations and identifying other steps that the community needs to take. PMID:24926829

  5. Sagnac secret sharing over telecom fiber networks.

    PubMed

    Bogdanski, Jan; Ahrens, Johan; Bourennane, Mohamed

    2009-01-19

    We report the first Sagnac quantum secret sharing (in three-and four-party implementations) over 1550 nm single mode fiber (SMF) networks, using a single qubit protocol with phase encoding. Our secret sharing experiment has been based on a single qubit protocol, which has opened the door to practical secret sharing implementation over fiber telecom channels and in free-space. The previous quantum secret sharing proposals were based on multiparticle entangled states, difficult in the practical implementation and not scalable. Our experimental data in the three-party implementation show stable (in regards to birefringence drift) quantum secret sharing transmissions at the total Sagnac transmission loop distances of 55-75 km with the quantum bit error rates (QBER) of 2.3-2.4% for the mean photon number micro?= 0.1 and 1.7-2.1% for micro= 0.3. In the four-party case we have achieved quantum secret sharing transmissions at the total Sagnac transmission loop distances of 45-55 km with the quantum bit error rates (QBER) of 3.0-3.7% for the mean photon number micro= 0.1 and 1.8-3.0% for micro?= 0.3. The stability of quantum transmission has been achieved thanks to our new concept for compensation of SMF birefringence effects in Sagnac, based on a polarization control system and a polarization insensitive phase modulator. The measurement results have showed feasibility of quantum secret sharing over telecom fiber networks in Sagnac configuration, using standard fiber telecom components.

  6. Device independence for two-party cryptography and position verification with memoryless devices

    NASA Astrophysics Data System (ADS)

    Ribeiro, Jérémy; Thinh, Le Phuc; Kaniewski, Jedrzej; Helsen, Jonas; Wehner, Stephanie

    2018-06-01

    Quantum communication has demonstrated its usefulness for quantum cryptography far beyond quantum key distribution. One domain is two-party cryptography, whose goal is to allow two parties who may not trust each other to solve joint tasks. Another interesting application is position-based cryptography whose goal is to use the geographical location of an entity as its only identifying credential. Unfortunately, security of these protocols is not possible against an all powerful adversary. However, if we impose some realistic physical constraints on the adversary, there exist protocols for which security can be proven, but these so far relied on the knowledge of the quantum operations performed during the protocols. In this work we improve the device-independent security proofs of Kaniewski and Wehner [New J. Phys. 18, 055004 (2016), 10.1088/1367-2630/18/5/055004] for two-party cryptography (with memoryless devices) and we add a security proof for device-independent position verification (also memoryless devices) under different physical constraints on the adversary. We assess the quality of the devices by observing a Bell violation, and, as for Kaniewski and Wehner [New J. Phys. 18, 055004 (2016), 10.1088/1367-2630/18/5/055004], security can be attained for any violation of the Clauser-Holt-Shimony-Horne inequality.

  7. Quantum Private Comparison of Equality Based on Five-Particle Cluster State

    NASA Astrophysics Data System (ADS)

    Chang, Yan; Zhang, Wen-Bo; Zhang, Shi-Bin; Wang, Hai-Chun; Yan, Li-Li; Han, Gui-Hua; Sheng, Zhi-Wei; Huang, Yuan-Yuan; Suo, Wang; Xiong, Jin-Xin

    2016-12-01

    A protocol for quantum private comparison of equality (QPCE) is proposed based on five-particle cluster state with the help of a semi-honest third party (TP). In our protocol, TP is allowed to misbehave on its own but can not conspire with either of two parties. Compared with most two-user QPCE protocols, our protocol not only can compare two groups of private information (each group has two users) in one execution, but also compare just two private information. Compared with the multi-user QPCE protocol proposed, our protocol is safer with more reasonable assumptions of TP. The qubit efficiency is computed and analyzed. Our protocol can also be generalized to the case of 2N participants with one TP. The 2N-participant protocol can compare two groups (each group has N private information) in one execution or just N private information. Supported by NSFC under Grant Nos. 61402058, 61572086, the Fund for Middle and Young Academic Leaders of CUIT under Grant No. J201511, the Science and Technology Support Project of Sichuan Province of China under Grant No. 2013GZX0137, the Fund for Young Persons Project of Sichuan Province of China under Grant No. 12ZB017, and the Foundation of Cyberspace Security Key Laboratory of Sichuan Higher Education Institutions under Grant No. szjj2014-074

  8. Counterfactual quantum certificate authorization

    NASA Astrophysics Data System (ADS)

    Shenoy H., Akshata; Srikanth, R.; Srinivas, T.

    2014-05-01

    We present a multipartite protocol in a counterfactual paradigm. In counterfactual quantum cryptography, secure information is transmitted between two spatially separated parties even when there is no physical travel of particles transferring the information between them. We propose here a tripartite counterfactual quantum protocol for the task of certificate authorization. Here a trusted third party, Alice, authenticates an entity Bob (e.g., a bank) that a client Charlie wishes to securely transact with. The protocol is counterfactual with respect to either Bob or Charlie. We prove its security against a general incoherent attack, where Eve attacks single particles.

  9. Quantum Private Comparison Protocol with Linear Optics

    NASA Astrophysics Data System (ADS)

    Luo, Qing-bin; Yang, Guo-wu; She, Kun; Li, Xiaoyu

    2016-12-01

    In this paper, we propose an innovative quantum private comparison(QPC) protocol based on partial Bell-state measurement from the view of linear optics, which enabling two parties to compare the equality of their private information with the help of a semi-honest third party. Partial Bell-state measurement has been realized by using only linear optical elements in experimental measurement-device-independent quantum key distribution(MDI-QKD) schemes, which makes us believe that our protocol can be realized in the near future. The security analysis shows that the participants will not leak their private information.

  10. Quantum solution to a class of two-party private summation problems

    NASA Astrophysics Data System (ADS)

    Shi, Run-Hua; Zhang, Shun

    2017-09-01

    In this paper, we define a class of special two-party private summation (S2PPS) problems and present a common quantum solution to S2PPS problems. Compared to related classical solutions, our solution has advantages of higher security and lower communication complexity, and especially it can ensure the fairness of two parties without the help of a third party. Furthermore, we investigate the practical applications of our proposed S2PPS protocol in many privacy-preserving settings with big data sets, including private similarity decision, anonymous authentication, social networks, secure trade negotiation, secure data mining.

  11. Quantum And Relativistic Protocols For Secure Multi-Party Computation

    NASA Astrophysics Data System (ADS)

    Colbeck, Roger

    2009-11-01

    After a general introduction, the thesis is divided into four parts. In the first, we discuss the task of coin tossing, principally in order to highlight the effect different physical theories have on security in a straightforward manner, but, also, to introduce a new protocol for non-relativistic strong coin tossing. This protocol matches the security of the best protocol known to date while using a conceptually different approach to achieve the task. In the second part variable bias coin tossing is introduced. This is a variant of coin tossing in which one party secretly chooses one of two biased coins to toss. It is shown that this can be achieved with unconditional security for a specified range of biases, and with cheat-evident security for any bias. We also discuss two further protocols which are conjectured to be unconditionally secure for any bias. The third section looks at other two-party secure computations for which, prior to our work, protocols and no-go theorems were unknown. We introduce a general model for such computations, and show that, within this model, a wide range of functions are impossible to compute securely. We give explicit cheating attacks for such functions. In the final chapter we discuss the task of expanding a private random string, while dropping the usual assumption that the protocol's user trusts her devices. Instead we assume that all quantum devices are supplied by an arbitrarily malicious adversary. We give two protocols that we conjecture securely perform this task. The first allows a private random string to be expanded by a finite amount, while the second generates an arbitrarily large expansion of such a string.

  12. An Efficient and Secure Arbitrary N-Party Quantum Key Agreement Protocol Using Bell States

    NASA Astrophysics Data System (ADS)

    Liu, Wen-Jie; Xu, Yong; Yang, Ching-Nung; Gao, Pei-Pei; Yu, Wen-Bin

    2018-01-01

    Two quantum key agreement protocols using Bell states and Bell measurement were recently proposed by Shukla et al. (Quantum Inf. Process. 13(11), 2391-2405, 2014). However, Zhu et al. pointed out that there are some security flaws and proposed an improved version (Quantum Inf. Process. 14(11), 4245-4254, 2015). In this study, we will show Zhu et al.'s improvement still exists some security problems, and its efficiency is not high enough. For solving these problems, we utilize four Pauli operations { I, Z, X, Y} to encode two bits instead of the original two operations { I, X} to encode one bit, and then propose an efficient and secure arbitrary N-party quantum key agreement protocol. In the protocol, the channel checking with decoy single photons is introduced to avoid the eavesdropper's flip attack, and a post-measurement mechanism is used to prevent against the collusion attack. The security analysis shows the present protocol can guarantee the correctness, security, privacy and fairness of quantum key agreement.

  13. Coherent-pulse implementations of quantum cryptography protocols resistant to photon-number-splitting attacks

    NASA Astrophysics Data System (ADS)

    Acín, Antonio; Gisin, Nicolas; Scarani, Valerio

    2004-01-01

    We propose a class of quantum cryptography protocols that are robust against photon-number-splitting attacks (PNS) in a weak coherent-pulse implementation. We give a quite exhaustive analysis of several eavesdropping attacks on these schemes. The honest parties (Alice and Bob) use present-day technology, in particular an attenuated laser as an approximation of a single-photon source. The idea of the protocols is to exploit the nonorthogonality of quantum states to decrease the information accessible to Eve due to the multiphoton pulses produced by the imperfect source. The distance at which the key distribution becomes insecure due to the PNS attack is significantly increased compared to the existing schemes. We also show that strong-pulse implementations, where a strong pulse is included as a reference, allow for key distribution robust against photon-number-splitting attacks.

  14. Unconditional security from noisy quantum storage

    NASA Astrophysics Data System (ADS)

    Wehner, Stephanie

    2010-03-01

    We consider the implementation of two-party cryptographic primitives based on the sole physical assumption that no large-scale reliable quantum storage is available to the cheating party. An important example of such a task is secure identification. Here, Alice wants to identify herself to Bob (possibly an ATM machine) without revealing her password. More generally, Alice and Bob wish to solve problems where Alice holds an input x (e.g. her password), and Bob holds an input y (e.g. the password an honest Alice should possess), and they want to obtain the value of some function f(x,y) (e.g. the equality function). Security means that the legitimate users should not learn anything beyond this specification. That is, Alice should not learn anything about y and Bob should not learn anything about x, other than what they may be able to infer from the value of f(x,y). We show that any such problem can be solved securely in the noisy-storage model by constructing protocols for bit commitment and oblivious transfer, where we prove security against the most general attack. Our protocols can be implemented with present-day hardware used for quantum key distribution. In particular, no quantum storage is required for the honest parties. Our work raises a large number of immediate theoretical as well as experimental questions related to many aspects of quantum information science, such as for example understanding the information carrying properties of quantum channels and memories, randomness extraction, min-entropy sampling, as well as constructing small handheld devices which are suitable for the task of secure identification. [4pt] Full version available at arXiv:0906.1030 (theoretical) and arXiv:0911.2302 (practically oriented).

  15. High-rate measurement-device-independent quantum cryptography

    NASA Astrophysics Data System (ADS)

    Pirandola, Stefano; Ottaviani, Carlo; Spedalieri, Gaetana; Weedbrook, Christian; Braunstein, Samuel L.; Lloyd, Seth; Gehring, Tobias; Jacobsen, Christian S.; Andersen, Ulrik L.

    2015-06-01

    Quantum cryptography achieves a formidable task—the remote distribution of secret keys by exploiting the fundamental laws of physics. Quantum cryptography is now headed towards solving the practical problem of constructing scalable and secure quantum networks. A significant step in this direction has been the introduction of measurement-device independence, where the secret key between two parties is established by the measurement of an untrusted relay. Unfortunately, although qubit-implemented protocols can reach long distances, their key rates are typically very low, unsuitable for the demands of a metropolitan network. Here we show, theoretically and experimentally, that a solution can come from the use of continuous-variable systems. We design a coherent-state network protocol able to achieve remarkably high key rates at metropolitan distances, in fact three orders of magnitude higher than those currently achieved. Our protocol could be employed to build high-rate quantum networks where devices securely connect to nearby access points or proxy servers.

  16. Comment I on ''Dense coding in entangled states''

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wojcik, Antoni; Grudka, Andrzej

    2003-07-01

    In this Comment we question the recent analysis of two dense coding protocols presented by Lee, Ahn, and Hwang [Phys. Rev. A 66, 024304 (2002)]. We argue that in the case of two-party communication protocol, there is no reason for using a maximally entangled state of more than two qubits.

  17. Fair and optimistic quantum contract signing

    NASA Astrophysics Data System (ADS)

    Paunković, N.; Bouda, J.; Mateus, P.

    2011-12-01

    We present a fair and optimistic quantum-contract-signing protocol between two clients that requires no communication with the third trusted party during the exchange phase. We discuss its fairness and show that it is possible to design such a protocol for which the probability of a dishonest client to cheat becomes negligible and scales as N-1/2, where N is the number of messages exchanged between the clients. Our protocol is not based on the exchange of signed messages: Its fairness is based on the laws of quantum mechanics. Thus, it is abuse free, and the clients do not have to generate new keys for each message during the exchange phase. We discuss a real-life scenario when measurement errors and qubit-state corruption due to noisy channels and imperfect quantum memories occur and argue that for a real, good-enough measurement apparatus, transmission channels, and quantum memories, our protocol would still be fair. Apart from stable quantum memories, the other segments of our protocol could be implemented by today's technology, as they require in essence the same type of apparatus as the one needed for the Bennett-Brassard 1984 (BB84) cryptographic protocol. Finally, we briefly discuss two alternative versions of the protocol, one that uses only two states [based on the Bennett 1992 (B92) protocol] and the other that uses entangled pairs, and show that it is possible to generalize our protocol to an arbitrary number of clients.

  18. Deterministic secure quantum communication using a single d-level system

    PubMed Central

    Jiang, Dong; Chen, Yuanyuan; Gu, Xuemei; Xie, Ling; Chen, Lijun

    2017-01-01

    Deterministic secure quantum communication (DSQC) can transmit secret messages between two parties without first generating a shared secret key. Compared with quantum key distribution (QKD), DSQC avoids the waste of qubits arising from basis reconciliation and thus reaches higher efficiency. In this paper, based on data block transmission and order rearrangement technologies, we propose a DSQC protocol. It utilizes a set of single d-level systems as message carriers, which are used to directly encode the secret message in one communication process. Theoretical analysis shows that these employed technologies guarantee the security, and the use of a higher dimensional quantum system makes our protocol achieve higher security and efficiency. Since only quantum memory is required for implementation, our protocol is feasible with current technologies. Furthermore, Trojan horse attack (THA) is taken into account in our protocol. We give a THA model and show that THA significantly increases the multi-photon rate and can thus be detected. PMID:28327557

  19. Eavesdropping on the improved three-party quantum secret sharing protocol

    NASA Astrophysics Data System (ADS)

    Gao, Gan

    2011-02-01

    Lin et al. [Song Lin, Fei Gao, Qiao-yan Wen, Fu-chen Zhu, Opt. Commun. 281 (2008) 4553] pointed out that the multiparty quantum secret sharing protocol [Zhan-jun Zhang, Gan Gao, Xin Wang, Lian-fang Han, Shou-hua Shi, Opt. Commun. 269 (2007) 418] is not secure and proposed an improved three-party quantum secret sharing protocol. In this paper, we study the security of the improved three-party quantum secret sharing protocol and find that it is still not secure. Finally, a further improved three-party quantum secret sharing protocol is proposed.

  20. Multi-party quantum private comparison based on the entanglement swapping of d-level cat states and d-level Bell states

    NASA Astrophysics Data System (ADS)

    Zhao-Xu, Ji; Tian-Yu, Ye

    2017-07-01

    In this paper, a novel multi-party quantum private comparison protocol with a semi-honest third party (TP) is proposed based on the entanglement swapping of d-level cat states and d-level Bell states. Here, TP is allowed to misbehave on his own, but will not conspire with any party. In our protocol, n parties employ unitary operations to encode their private secrets and can compare the equality of their private secrets within one time execution of the protocol. Our protocol can withstand both the outside attacks and the participant attacks on the condition that none of the QKD methods is adopted to generate keys for security. One party cannot obtain other parties' secrets except for the case that their secrets are identical. The semi-honest TP cannot learn any information about these parties' secrets except the end comparison result on whether all private secrets from n parties are equal.

  1. Experimental measurement-device-independent quantum key distribution with uncharacterized encoding.

    PubMed

    Wang, Chao; Wang, Shuang; Yin, Zhen-Qiang; Chen, Wei; Li, Hong-Wei; Zhang, Chun-Mei; Ding, Yu-Yang; Guo, Guang-Can; Han, Zheng-Fu

    2016-12-01

    Measurement-device-independent quantum key distribution (MDI QKD) is an efficient way to share secrets using untrusted measurement devices. However, the assumption on the characterizations of encoding states is still necessary in this promising protocol, which may lead to unnecessary complexity and potential loopholes in realistic implementations. Here, by using the mismatched-basis statistics, we present the first proof-of-principle experiment of MDI QKD with uncharacterized encoding sources. In this demonstration, the encoded states are only required to be constrained in a two-dimensional Hilbert space, and two distant parties (Alice and Bob) are resistant to state preparation flaws even if they have no idea about the detailed information of their encoding states. The positive final secure key rates of our system exhibit the feasibility of this novel protocol, and demonstrate its value for the application of secure communication with uncharacterized devices.

  2. Experimental loss-tolerant quantum coin flipping

    PubMed Central

    Berlín, Guido; Brassard, Gilles; Bussières, Félix; Godbout, Nicolas; Slater, Joshua A.; Tittel, Wolfgang

    2011-01-01

    Coin flipping is a cryptographic primitive in which two distrustful parties wish to generate a random bit to choose between two alternatives. This task is impossible to realize when it relies solely on the asynchronous exchange of classical bits: one dishonest player has complete control over the final outcome. It is only when coin flipping is supplemented with quantum communication that this problem can be alleviated, although partial bias remains. Unfortunately, practical systems are subject to loss of quantum data, which allows a cheater to force a bias that is complete or arbitrarily close to complete in all previous protocols and implementations. Here we report on the first experimental demonstration of a quantum coin-flipping protocol for which loss cannot be exploited to cheat better. By eliminating the problem of loss, which is unavoidable in any realistic setting, quantum coin flipping takes a significant step towards real-world applications of quantum communication. PMID:22127057

  3. PROFILE: Environmental Impact Assessment Under the National Environmental Policy Act and the Protocol on Environmental Protection to the Antarctic Treaty.

    PubMed

    Ensminger; McCold; Webb

    1999-07-01

    / Antarctica has been set aside by the international community for protection as a natural reserve and a place for scientific research. Through the Antarctic Treaty of 1961, the signing nations agreed to cooperate in protecting the antarctic environment, in conducting scientific studies, and in abstaining from the exercise of territorial claims. The 1991 signing of the Protocol on Environmental Protection to the Antarctic Treaty (Protocol) by representatives of the 26 nations comprising the Antarctic Treaty Consultative Parties (Parties) significantly strengthened environmental protection measures for the continent. The Protocol required ratification by each of the governments individually prior to official implementation. The US government ratified the Protocol by passage of the Antarctic Science, Tourism, and Conservation Act of 1997. Japan completed the process by ratifying the Protocol on December 15, 1997. US government actions undertaken in Antarctica are subject to the requirements of both the Protocol and the US National Environmental Policy Act (NEPA). There are differences in the scope and intent of the Protocol and NEPA; however, both require environmental impact assessment (EIA) as part of the planning process for proposed actions that have the potential for environmental impacts. In this paper we describe the two instruments and highlight key similarities and differences with particular attention to EIA. Through this comparison of the EIA requirements of NEPA and the Protocol, we show how the requirements of each can be used in concert to provide enhanced environmental protection for the antarctic environment. NEPA applies only to actions of the US government; therefore, because NEPA includes certain desirable attributes that have been refined and clarified through numerous court cases, and because the Protocol is just entering implementation internationally, some recommendations are made for strengthening the procedural requirements of the Protocol for activities undertaken by all Parties in Antarctica. The Protocol gives clear and strong guidance for protection of specific, valued antarctic environmental resources including intrinsic wilderness and aesthetic values, and the value of Antarctica as an area for scientific research. That guidance requires a higher standard of environmental protection for Antarctica than is required in other parts of the world. This paper shows that taken together NEPA and the Protocol call for closer examination of proposed actions and a more rigorous consideration of environmental impacts than either would alone. Three areas are identified where the EIA provisions of the Protocol could be strengthened to improve its effectiveness. First, the thresholds defined by the Protocol need to be clarified. Specifically, the meanings of the terms "minor" and "transitory" are not clear in the context of the Protocol. The use of "or" in the phrase "minor or transitory" further confuses the meaning. Second, cumulative impact assessment is called for by the Protocol but is not defined. A clear definition could reduce the chance that cumulative impacts would be given inadequate consideration. Finally, the public has limited opportunities to comment on or influence the preparation of initial or comprehensive environmental evaluations. Experience has shown that public input to environmental documents has a considerable influence on agency decision making and the quality of EIA that agencies perform.KEY WORDS: Environment; Impact assessment; Antarctica; NEPA; Protocol; Antarctic Treatyhttp://link.springer-ny.com/link/service/journals/00267/bibs/24n1p13.html

  4. 33 CFR 151.21 - Ships of countries not party to MARPOL 73/78.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Implementation of MARPOL 73/78 and the Protocol on Environmental Protection to the Antarctic Treaty as it Pertains to Pollution from Ships Oil Pollution § 151.21 Ships of...

  5. 33 CFR 151.21 - Ships of countries not party to MARPOL 73/78.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Implementation of MARPOL 73/78 and the Protocol on Environmental Protection to the Antarctic Treaty as it Pertains to Pollution from Ships Oil Pollution § 151.21 Ships of...

  6. 33 CFR 151.21 - Ships of countries not party to MARPOL 73/78.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Implementation of MARPOL 73/78 and the Protocol on Environmental Protection to the Antarctic Treaty as it Pertains to Pollution from Ships Oil Pollution § 151.21 Ships of...

  7. 33 CFR 151.21 - Ships of countries not party to MARPOL 73/78.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Implementation of MARPOL 73/78 and the Protocol on Environmental Protection to the Antarctic Treaty as it Pertains to Pollution from Ships Oil Pollution § 151.21 Ships of...

  8. 33 CFR 151.21 - Ships of countries not party to MARPOL 73/78.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SECURITY (CONTINUED) POLLUTION VESSELS CARRYING OIL, NOXIOUS LIQUID SUBSTANCES, GARBAGE, MUNICIPAL OR COMMERCIAL WASTE, AND BALLAST WATER Implementation of MARPOL 73/78 and the Protocol on Environmental Protection to the Antarctic Treaty as it Pertains to Pollution from Ships Oil Pollution § 151.21 Ships of...

  9. Coherent-pulse implementations of quantum cryptography protocols resistant to photon-number-splitting attacks

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Acin, Antonio; Gisin, Nicolas; Scarani, Valerio

    2004-01-01

    We propose a class of quantum cryptography protocols that are robust against photon-number-splitting attacks (PNS) in a weak coherent-pulse implementation. We give a quite exhaustive analysis of several eavesdropping attacks on these schemes. The honest parties (Alice and Bob) use present-day technology, in particular an attenuated laser as an approximation of a single-photon source. The idea of the protocols is to exploit the nonorthogonality of quantum states to decrease the information accessible to Eve due to the multiphoton pulses produced by the imperfect source. The distance at which the key distribution becomes insecure due to the PNS attack is significantlymore » increased compared to the existing schemes. We also show that strong-pulse implementations, where a strong pulse is included as a reference, allow for key distribution robust against photon-number-splitting attacks.« less

  10. 40 CFR 82.15 - Prohibitions for class II controlled substances.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... to the Montreal Protocol that has ratified the Beijing Amendments. Parties that have ratified the... Party to the Montreal Protocol that has provided notice, certification, and data in accordance with... by the Ozone Secretariat. Or, (3) A Party to the Montreal Protocol operating under Article 5(1) to...

  11. 40 CFR 82.15 - Prohibitions for class II controlled substances.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... to the Montreal Protocol that has ratified the Beijing Amendments. Parties that have ratified the... Party to the Montreal Protocol that has provided notice, certification, and data in accordance with... by the Ozone Secretariat. Or, (3) A Party to the Montreal Protocol operating under Article 5(1) to...

  12. Multi-party quantum key agreement protocol secure against collusion attacks

    NASA Astrophysics Data System (ADS)

    Wang, Ping; Sun, Zhiwei; Sun, Xiaoqiang

    2017-07-01

    The fairness of a secure multi-party quantum key agreement (MQKA) protocol requires that all involved parties are entirely peer entities and can equally influence the outcome of the protocol to establish a shared key wherein no one can decide the shared key alone. However, it is found that parts of the existing MQKA protocols are sensitive to collusion attacks, i.e., some of the dishonest participants can collaborate to predetermine the final key without being detected. In this paper, a multi-party QKA protocol resisting collusion attacks is proposed. Different from previous QKA protocol resisting N-1 coconspirators or resisting 1 coconspirators, we investigate the general circle-type MQKA protocol which can be secure against t dishonest participants' cooperation. Here, t < N. We hope the results of the presented paper will be helpful for further research on fair MQKA protocols.

  13. Usage of the hybrid encryption in a cloud instant messages exchange system

    NASA Astrophysics Data System (ADS)

    Kvyetnyy, Roman N.; Romanyuk, Olexander N.; Titarchuk, Evgenii O.; Gromaszek, Konrad; Mussabekov, Nazarbek

    2016-09-01

    A new approach for constructing cloud instant messaging represented in this article allows users to encrypt data locally by using Diffie - Hellman key exchange protocol. The described approach allows to construct a cloud service which operates only by users encrypted messages; encryption and decryption takes place locally at the user party using a symmetric AES encryption. A feature of the service is the conferences support without the need for messages reecryption for each participant. In the article it is given an example of the protocol implementation on the ECC and RSA encryption algorithms basis, as well as a comparison of these implementations.

  14. Novel Multi-Party Quantum Key Agreement Protocol with G-Like States and Bell States

    NASA Astrophysics Data System (ADS)

    Min, Shi-Qi; Chen, Hua-Ying; Gong, Li-Hua

    2018-03-01

    A significant aspect of quantum cryptography is quantum key agreement (QKA), which ensures the security of key agreement protocols by quantum information theory. The fairness of an absolute security multi-party quantum key agreement (MQKA) protocol demands that all participants can affect the protocol result equally so as to establish a shared key and that nobody can determine the shared key by himself/herself. We found that it is difficult for the existing multi-party quantum key agreement protocol to withstand the collusion attacks. Put differently, it is possible for several cooperated and untruthful participants to determine the final key without being detected. To address this issue, based on the entanglement swapping between G-like state and Bell states, a new multi-party quantum key agreement protocol is put forward. The proposed protocol makes full use of EPR pairs as quantum resources, and adopts Bell measurement and unitary operation to share a secret key. Besides, the proposed protocol is fair, secure and efficient without involving a third party quantum center. It demonstrates that the protocol is capable of protecting users' privacy and meeting the requirement of fairness. Moreover, it is feasible to carry out the protocol with existing technologies.

  15. Novel Multi-Party Quantum Key Agreement Protocol with G-Like States and Bell States

    NASA Astrophysics Data System (ADS)

    Min, Shi-Qi; Chen, Hua-Ying; Gong, Li-Hua

    2018-06-01

    A significant aspect of quantum cryptography is quantum key agreement (QKA), which ensures the security of key agreement protocols by quantum information theory. The fairness of an absolute security multi-party quantum key agreement (MQKA) protocol demands that all participants can affect the protocol result equally so as to establish a shared key and that nobody can determine the shared key by himself/herself. We found that it is difficult for the existing multi-party quantum key agreement protocol to withstand the collusion attacks. Put differently, it is possible for several cooperated and untruthful participants to determine the final key without being detected. To address this issue, based on the entanglement swapping between G-like state and Bell states, a new multi-party quantum key agreement protocol is put forward. The proposed protocol makes full use of EPR pairs as quantum resources, and adopts Bell measurement and unitary operation to share a secret key. Besides, the proposed protocol is fair, secure and efficient without involving a third party quantum center. It demonstrates that the protocol is capable of protecting users' privacy and meeting the requirement of fairness. Moreover, it is feasible to carry out the protocol with existing technologies.

  16. Entanglement concentration and purification of two-mode squeezed microwave photons in circuit QED

    NASA Astrophysics Data System (ADS)

    Zhang, Hao; Alsaedi, Ahmed; Hayat, Tasawar; Deng, Fu-Guo

    2018-04-01

    We present a theoretical proposal for a physical implementation of entanglement concentration and purification protocols for two-mode squeezed microwave photons in circuit quantum electrodynamics (QED). First, we give the description of the cross-Kerr effect induced between two resonators in circuit QED. Then we use the cross-Kerr media to design the effective quantum nondemolition (QND) measurement on microwave-photon number. By using the QND measurement, the parties in quantum communication can accomplish the entanglement concentration and purification of nonlocal two-mode squeezed microwave photons. We discuss the feasibility of our schemes by giving the detailed parameters which can be realized with current experimental technology. Our work can improve some practical applications in continuous-variable microwave-based quantum information processing.

  17. A large-alphabet three-party quantum key distribution protocol based on orbital and spin angular momenta hybrid entanglement

    NASA Astrophysics Data System (ADS)

    Lai, Hong; Luo, Mingxing; Zhang, Jun; Pieprzyk, Josef; Pan, Lei; Orgun, Mehmet A.

    2018-07-01

    The orthogonality of the orbital angular momentum (OAM) eigenstates enables a single photon carry an arbitrary number of bits. Moreover, additional degrees of freedom (DOFs) of OAM can span a high-dimensional Hilbert space, which could greatly increase information capacity and security. Moreover, the use of the spin angular momentum-OAM hybrid entangled state can increase Shannon dimensionality, because photons can be hybrid entangled in multiple DOFs. Based on these observations, we develop a hybrid entanglement quantum key distribution (QKD) protocol to achieve three-party quantum key distribution without classical message exchanges. In our proposed protocol, a communicating party uses a spatial light modulator (SLM) and a specific phase hologram to modulate photons' OAM state. Similarly, the other communicating parties use their SLMs and the fixed different phase holograms to modulate the OAM entangled photon pairs, producing the shared key among the parties Alice, Bob and Charlie without classical message exchanges. More importantly, when the same operation is repeated for every party, our protocol could be extended to a multiple-party QKD protocol.

  18. Rainbow correlation imaging with macroscopic twin beam

    NASA Astrophysics Data System (ADS)

    Allevi, Alessia; Bondani, Maria

    2017-06-01

    We present the implementation of a correlation-imaging protocol that exploits both the spatial and spectral correlations of macroscopic twin-beam states generated by parametric downconversion. In particular, the spectral resolution of an imaging spectrometer coupled to an EMCCD camera is used in a proof-of-principle experiment to encrypt and decrypt a simple code to be transmitted between two parties. In order to optimize the trade-off between visibility and resolution, we provide the characterization of the correlation images as a function of the spatio-spectral properties of twin beams generated at different pump power values.

  19. Counterfactual quantum cryptography.

    PubMed

    Noh, Tae-Gon

    2009-12-04

    Quantum cryptography allows one to distribute a secret key between two remote parties using the fundamental principles of quantum mechanics. The well-known established paradigm for the quantum key distribution relies on the actual transmission of signal particle through a quantum channel. In this Letter, we show that the task of a secret key distribution can be accomplished even though a particle carrying secret information is not in fact transmitted through the quantum channel. The proposed protocols can be implemented with current technologies and provide practical security advantages by eliminating the possibility that an eavesdropper can directly access the entire quantum system of each signal particle.

  20. Counterfactual Quantum Cryptography

    NASA Astrophysics Data System (ADS)

    Noh, Tae-Gon

    2009-12-01

    Quantum cryptography allows one to distribute a secret key between two remote parties using the fundamental principles of quantum mechanics. The well-known established paradigm for the quantum key distribution relies on the actual transmission of signal particle through a quantum channel. In this Letter, we show that the task of a secret key distribution can be accomplished even though a particle carrying secret information is not in fact transmitted through the quantum channel. The proposed protocols can be implemented with current technologies and provide practical security advantages by eliminating the possibility that an eavesdropper can directly access the entire quantum system of each signal particle.

  1. Proposal for founding mistrustful quantum cryptography on coin tossing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kent, Adrian; Hewlett-Packard Laboratories, Filton Road, Stoke Gifford, Bristol BS34 8QZ,

    2003-07-01

    A significant branch of classical cryptography deals with the problems which arise when mistrustful parties need to generate, process, or exchange information. As Kilian showed a while ago, mistrustful classical cryptography can be founded on a single protocol, oblivious transfer, from which general secure multiparty computations can be built. The scope of mistrustful quantum cryptography is limited by no-go theorems, which rule out, inter alia, unconditionally secure quantum protocols for oblivious transfer or general secure two-party computations. These theorems apply even to protocols which take relativistic signaling constraints into account. The best that can be hoped for, in general, aremore » quantum protocols which are computationally secure against quantum attack. Here a method is described for building a classically certified bit commitment, and hence every other mistrustful cryptographic task, from a secure coin-tossing protocol. No security proof is attempted, but reasons are sketched why these protocols might resist quantum computational attack.« less

  2. Completely device-independent quantum key distribution

    NASA Astrophysics Data System (ADS)

    Aguilar, Edgar A.; Ramanathan, Ravishankar; Kofler, Johannes; Pawłowski, Marcin

    2016-08-01

    Quantum key distribution (QKD) is a provably secure way for two distant parties to establish a common secret key, which then can be used in a classical cryptographic scheme. Using quantum entanglement, one can reduce the necessary assumptions that the parties have to make about their devices, giving rise to device-independent QKD (DIQKD). However, in all existing protocols to date the parties need to have an initial (at least partially) random seed as a resource. In this work, we show that this requirement can be dropped. Using recent advances in the fields of randomness amplification and randomness expansion, we demonstrate that it is sufficient for the message the parties want to communicate to be (partially) unknown to the adversaries—an assumption without which any type of cryptography would be pointless to begin with. One party can use her secret message to locally generate a secret sequence of bits, which can then be openly used by herself and the other party in a DIQKD protocol. Hence our work reduces the requirements needed to perform secure DIQKD and establish safe communication.

  3. Security of two-state and four-state practical quantum bit-commitment protocols

    NASA Astrophysics Data System (ADS)

    Loura, Ricardo; Arsenović, Dušan; Paunković, Nikola; Popović, Duška B.; Prvanović, Slobodan

    2016-12-01

    We study cheating strategies against a practical four-state quantum bit-commitment protocol [A. Danan and L. Vaidman, Quant. Info. Proc. 11, 769 (2012)], 10.1007/s11128-011-0284-4 and its two-state variant [R. Loura et al., Phys. Rev. A 89, 052336 (2014)], 10.1103/PhysRevA.89.052336 when the underlying quantum channels are noisy and the cheating party is constrained to using single-qubit measurements only. We show that simply inferring the transmitted photons' states by using the Breidbart basis, optimal for ambiguous (minimum-error) state discrimination, does not directly produce an optimal cheating strategy for this bit-commitment protocol. We introduce a strategy, based on certain postmeasurement processes and show it to have better chances at cheating than the direct approach. We also study to what extent sending forged geographical coordinates helps a dishonest party in breaking the binding security requirement. Finally, we investigate the impact of imperfect single-photon sources in the protocols. Our study shows that, in terms of the resources used, the four-state protocol is advantageous over the two-state version. The analysis performed can be straightforwardly generalized to any finite-qubit measurement, with the same qualitative results.

  4. Achieving the physical limits of the bounded-storage model

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mandayam, Prabha; Wehner, Stephanie; Centre for Quantum Technologies, National University of Singapore, 2 Science Drive 3, 117543 Singapore

    2011-02-15

    Secure two-party cryptography is possible if the adversary's quantum storage device suffers imperfections. For example, security can be achieved if the adversary can store strictly less then half of the qubits transmitted during the protocol. This special case is known as the bounded-storage model, and it has long been an open question whether security can still be achieved if the adversary's storage were any larger. Here, we answer this question positively and demonstrate a two-party protocol which is secure as long as the adversary cannot store even a small fraction of the transmitted pulses. We also show that security canmore » be extended to a larger class of noisy quantum memories.« less

  5. Secure alignment of coordinate systems using quantum correlation

    NASA Astrophysics Data System (ADS)

    Rezazadeh, F.; Mani, A.; Karimipour, V.

    2017-08-01

    We show that two parties far apart can use shared entangled states and classical communication to align their coordinate systems with a very high fidelity. Moreover, compared with previous methods proposed for such a task, i.e., sending parallel or antiparallel pairs or groups of spin states, our method has the extra advantages of using single-qubit measurements and also being secure, so that third parties do not extract any information about the aligned coordinate system established between the two parties. The latter property is important in many other quantum information protocols in which measurements inevitably play a significant role.

  6. Counterfactual quantum cloning without transmitting any physical particles

    NASA Astrophysics Data System (ADS)

    Guo, Qi; Zhai, Shuqin; Cheng, Liu-Yong; Wang, Hong-Fu; Zhang, Shou

    2017-11-01

    We propose a counterfactual 1 →2 economical phase-covariant cloning scheme. Compared with the existing protocols using flying qubits, the main difference of the presented scheme is that the cloning can be achieved without transmitting the photon between the two parties. In addition, this counterfactual scheme does not need to construct controlled quantum gates to perform joint logical operations between the cloned qubit and the blank copy. We also numerically evaluate the performance of the present scheme in the practical experiment, which shows this cloning scheme can be implemented with a high success of probability and the fidelity is close to the optimal value in the ideal asymptotic limit.

  7. Multi-Party Privacy-Preserving Set Intersection with Quasi-Linear Complexity

    NASA Astrophysics Data System (ADS)

    Cheon, Jung Hee; Jarecki, Stanislaw; Seo, Jae Hong

    Secure computation of the set intersection functionality allows n parties to find the intersection between their datasets without revealing anything else about them. An efficient protocol for such a task could have multiple potential applications in commerce, health care, and security. However, all currently known secure set intersection protocols for n>2 parties have computational costs that are quadratic in the (maximum) number of entries in the dataset contributed by each party, making secure computation of the set intersection only practical for small datasets. In this paper, we describe the first multi-party protocol for securely computing the set intersection functionality with both the communication and the computation costs that are quasi-linear in the size of the datasets. For a fixed security parameter, our protocols require O(n2k) bits of communication and Õ(n2k) group multiplications per player in the malicious adversary setting, where k is the size of each dataset. Our protocol follows the basic idea of the protocol proposed by Kissner and Song, but we gain efficiency by using different representations of the polynomials associated with users' datasets and careful employment of algorithms that interpolate or evaluate polynomials on multiple points more efficiently. Moreover, the proposed protocol is robust. This means that the protocol outputs the desired result even if some corrupted players leave during the execution of the protocol.

  8. Cryptanalysis of the Quantum Private Comparison Protocol Based on the Entanglement Swapping Between Three-Particle W-Class State and Bell State

    NASA Astrophysics Data System (ADS)

    Gao, Xiang; Zhang, Shi-Bin; Chang, Yan; Yang, Fan; Zhang, Yan

    2018-02-01

    Recently, Li et al. (Int. J. Theor. Phys. 55, 1710-1718, 2016) proposed a Quantum Private Comparison (QPC) protocol based on the Entanglement Swapping Between Three-Particle W-Class State and Bell State. Two parties can check whether their secret information is equal or not with the help of the semi-honest third party (TP). However in this paper, we will point out this kind of semi-honest TP is unreasonable. If we relax the constraint of the semi-honest TP, by using the fake signal attack, TP can know the whole secret information illegally. At last, we give our improvement, which can make this protocol more secure.

  9. Cryptanalysis of the Quantum Private Comparison Protocol Based on the Entanglement Swapping Between Three-Particle W-Class State and Bell State

    NASA Astrophysics Data System (ADS)

    Gao, Xiang; Zhang, Shi-Bin; Chang, Yan; Yang, Fan; Zhang, Yan

    2018-06-01

    Recently, Li et al. (Int. J. Theor. Phys. 55, 1710-1718, 2016) proposed a Quantum Private Comparison (QPC) protocol based on the Entanglement Swapping Between Three-Particle W-Class State and Bell State. Two parties can check whether their secret information is equal or not with the help of the semi-honest third party (TP). However in this paper, we will point out this kind of semi-honest TP is unreasonable. If we relax the constraint of the semi-honest TP, by using the fake signal attack, TP can know the whole secret information illegally. At last, we give our improvement, which can make this protocol more secure.

  10. A Framework for Bounding Nonlocality of State Discrimination

    NASA Astrophysics Data System (ADS)

    Childs, Andrew M.; Leung, Debbie; Mančinska, Laura; Ozols, Maris

    2013-11-01

    We consider the class of protocols that can be implemented by local quantum operations and classical communication (LOCC) between two parties. In particular, we focus on the task of discriminating a known set of quantum states by LOCC. Building on the work in the paper Quantum nonlocality without entanglement (Bennett et al., Phys Rev A 59:1070-1091, 1999), we provide a framework for bounding the amount of nonlocality in a given set of bipartite quantum states in terms of a lower bound on the probability of error in any LOCC discrimination protocol. We apply our framework to an orthonormal product basis known as the domino states and obtain an alternative and simplified proof that quantifies its nonlocality. We generalize this result for similar bases in larger dimensions, as well as the “rotated” domino states, resolving a long-standing open question (Bennett et al., Phys Rev A 59:1070-1091, 1999).

  11. Experimental bit commitment based on quantum communication and special relativity.

    PubMed

    Lunghi, T; Kaniewski, J; Bussières, F; Houlmann, R; Tomamichel, M; Kent, A; Gisin, N; Wehner, S; Zbinden, H

    2013-11-01

    Bit commitment is a fundamental cryptographic primitive in which Bob wishes to commit a secret bit to Alice. Perfectly secure bit commitment between two mistrustful parties is impossible through asynchronous exchange of quantum information. Perfect security is however possible when Alice and Bob split into several agents exchanging classical and quantum information at times and locations suitably chosen to satisfy specific relativistic constraints. Here we report on an implementation of a bit commitment protocol using quantum communication and special relativity. Our protocol is based on [A. Kent, Phys. Rev. Lett. 109, 130501 (2012)] and has the advantage that it is practically feasible with arbitrary large separations between the agents in order to maximize the commitment time. By positioning agents in Geneva and Singapore, we obtain a commitment time of 15 ms. A security analysis considering experimental imperfections and finite statistics is presented.

  12. Proof-of-principle test of coherent-state continuous variable quantum key distribution through turbulent atmosphere (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Derkach, Ivan D.; Peuntinger, Christian; Ruppert, László; Heim, Bettina; Gunthner, Kevin; Usenko, Vladyslav C.; Elser, Dominique; Marquardt, Christoph; Filip, Radim; Leuchs, Gerd

    2016-10-01

    Continuous-variable quantum key distribution is a practical application of quantum information theory that is aimed at generation of secret cryptographic key between two remote trusted parties and that uses multi-photon quantum states as carriers of key bits. Remote parties share the secret key via a quantum channel, that presumably is under control of of an eavesdropper, and which properties must be taken into account in the security analysis. Well-studied fiber-optical quantum channels commonly possess stable transmittance and low noise levels, while free-space channels represent a simpler, less demanding and more flexible alternative, but suffer from atmospheric effects such as turbulence that in particular causes a non-uniform transmittance distribution referred to as fading. Nonetheless free-space channels, providing an unobstructed line-of-sight, are more apt for short, mid-range and potentially long-range (using satellites) communication and will play an important role in the future development and implementation of QKD networks. It was previously theoretically shown that coherent-state CV QKD should be in principle possible to implement over a free-space fading channel, but strong transmittance fluctuations result in the significant modulation-dependent channel excess noise. In this regime the post-selection of highly transmitting sub-channels may be needed, which can even restore the security of the protocol in the strongly turbulent channels. We now report the first proof-of-principle experimental test of coherent state CV QKD protocol using different levels Gaussian modulation over a mid-range (1.6-kilometer long) free-space atmospheric quantum channel. The transmittance of the link was characterized using intensity measurements for the reference but channel estimation using the modulated coherent states was also studied. We consider security against Gaussian collective attacks, that were shown to be optimal against CV QKD protocols . We assumed a general entangling cloner collective attack (modeled using data obtained from the state measurement results on both trusted sides of the protocol), that allows to purify the noise added in the quantum channel . Our security analysis of coherent-state protocol also took into account the effect of imperfect channel estimation, limited post-processing efficiency and finite data ensemble size on the performance of the protocol. In this regime we observe the positive key rate even without the need of applying post-selection. We show the positive improvement of the key rate with increase of the modulation variance, still remaining low enough to tolerate the transmittance fluctuations. The obtained results show that coherent-state CV QKD protocol that uses real free-space atmospheric channel can withstand negative influence of transmittance fluctuations, limited post-processing efficiency, imperfect channel estimation and other finite-size effects, and be successfully implemented. Our result paves the way to the full-scale implementation of the CV QKD in real free-space channels at mid-range distances.

  13. Two-Step Deterministic Remote Preparation of an Arbitrary Quantum State

    NASA Astrophysics Data System (ADS)

    Wang, Mei-Yu; Yan, Feng-Li

    2010-11-01

    We present a two-step deterministic remote state preparation protocol for an arbitrary quhit with the aid of a three-particle Greenberger—Horne—Zeilinger state. Generalization of this protocol for higher-dimensional Hilbert space systems among three parties is also given. We show that only single-particle von Neumann measurements, local operations, and classical communication are necessary. Moreover, since the overall information of the quantum state can be divided into two different pieces, which may be at different locations, this protocol may be useful in the quantum information field.

  14. Three-step semiquantum secure direct communication protocol

    NASA Astrophysics Data System (ADS)

    Zou, XiangFu; Qiu, DaoWen

    2014-09-01

    Quantum secure direct communication is the direct communication of secret messages without need for establishing a shared secret key first. In the existing schemes, quantum secure direct communication is possible only when both parties are quantum. In this paper, we construct a three-step semiquantum secure direct communication (SQSDC) protocol based on single photon sources in which the sender Alice is classical. In a semiquantum protocol, a person is termed classical if he (she) can measure, prepare and send quantum states only with the fixed orthogonal quantum basis {|0>, |1>}. The security of the proposed SQSDC protocol is guaranteed by the complete robustness of semiquantum key distribution protocols and the unconditional security of classical one-time pad encryption. Therefore, the proposed SQSDC protocol is also completely robust. Complete robustness indicates that nonzero information acquired by an eavesdropper Eve on the secret message implies the nonzero probability that the legitimate participants can find errors on the bits tested by this protocol. In the proposed protocol, we suggest a method to check Eves disturbing in the doves returning phase such that Alice does not need to announce publicly any position or their coded bits value after the photons transmission is completed. Moreover, the proposed SQSDC protocol can be implemented with the existing techniques. Compared with many quantum secure direct communication protocols, the proposed SQSDC protocol has two merits: firstly the sender only needs classical capabilities; secondly to check Eves disturbing after the transmission of quantum states, no additional classical information is needed.

  15. On the security of a simple three-party key exchange protocol without server's public keys.

    PubMed

    Nam, Junghyun; Choo, Kim-Kwang Raymond; Park, Minkyu; Paik, Juryon; Won, Dongho

    2014-01-01

    Authenticated key exchange protocols are of fundamental importance in securing communications and are now extensively deployed for use in various real-world network applications. In this work, we reveal major previously unpublished security vulnerabilities in the password-based authenticated three-party key exchange protocol according to Lee and Hwang (2010): (1) the Lee-Hwang protocol is susceptible to a man-in-the-middle attack and thus fails to achieve implicit key authentication; (2) the protocol cannot protect clients' passwords against an offline dictionary attack; and (3) the indistinguishability-based security of the protocol can be easily broken even in the presence of a passive adversary. We also propose an improved password-based authenticated three-party key exchange protocol that addresses the security vulnerabilities identified in the Lee-Hwang protocol.

  16. On the Security of a Simple Three-Party Key Exchange Protocol without Server's Public Keys

    PubMed Central

    Nam, Junghyun; Choo, Kim-Kwang Raymond; Park, Minkyu; Paik, Juryon; Won, Dongho

    2014-01-01

    Authenticated key exchange protocols are of fundamental importance in securing communications and are now extensively deployed for use in various real-world network applications. In this work, we reveal major previously unpublished security vulnerabilities in the password-based authenticated three-party key exchange protocol according to Lee and Hwang (2010): (1) the Lee-Hwang protocol is susceptible to a man-in-the-middle attack and thus fails to achieve implicit key authentication; (2) the protocol cannot protect clients' passwords against an offline dictionary attack; and (3) the indistinguishability-based security of the protocol can be easily broken even in the presence of a passive adversary. We also propose an improved password-based authenticated three-party key exchange protocol that addresses the security vulnerabilities identified in the Lee-Hwang protocol. PMID:25258723

  17. Semiquantum secret sharing using entangled states

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li Qin; Department of Computer Science, Sun Yat-sen University, Guangzhou 510006; Department of Mathematics, Hong Kong Baptist University, Kowloon

    Secret sharing is a procedure for sharing a secret among a number of participants such that only the qualified subsets of participants have the ability to reconstruct the secret. Even in the presence of eavesdropping, secret sharing can be achieved when all the members are quantum. So what happens if not all the members are quantum? In this paper, we propose two semiquantum secret sharing protocols by using maximally entangled Greenberger-Horne-Zeilinger-type states in which quantum Alice shares a secret with two classical parties, Bob and Charlie, in a way that both parties are sufficient to obtain the secret, but onemore » of them cannot. The presented protocols are also shown to be secure against eavesdropping.« less

  18. Multi-party quantum summation without a trusted third party based on single particles

    NASA Astrophysics Data System (ADS)

    Zhang, Cai; Situ, Haozhen; Huang, Qiong; Yang, Pingle

    We propose multi-party quantum summation protocols based on single particles, in which participants are allowed to compute the summation of their inputs without the help of a trusted third party and preserve the privacy of their inputs. Only one participant who generates the source particles needs to perform unitary operations and only single particles are needed in the beginning of the protocols.

  19. Device-independent quantum key distribution

    NASA Astrophysics Data System (ADS)

    Hänggi, Esther

    2010-12-01

    In this thesis, we study two approaches to achieve device-independent quantum key distribution: in the first approach, the adversary can distribute any system to the honest parties that cannot be used to communicate between the three of them, i.e., it must be non-signalling. In the second approach, we limit the adversary to strategies which can be implemented using quantum physics. For both approaches, we show how device-independent quantum key distribution can be achieved when imposing an additional condition. In the non-signalling case this additional requirement is that communication is impossible between all pairwise subsystems of the honest parties, while, in the quantum case, we demand that measurements on different subsystems must commute. We give a generic security proof for device-independent quantum key distribution in these cases and apply it to an existing quantum key distribution protocol, thus proving its security even in this setting. We also show that, without any additional such restriction there always exists a successful joint attack by a non-signalling adversary.

  20. Nonlocal hyperconcentration on entangled photons using photonic module system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cao, Cong; Wang, Tie-Jun; Mi, Si-Chen

    Entanglement distribution will inevitably be affected by the channel and environment noise. Thus distillation of maximal entanglement nonlocally becomes a crucial goal in quantum information. Here we illustrate that maximal hyperentanglement on nonlocal photons could be distilled using the photonic module and cavity quantum electrodynamics, where the photons are simultaneously entangled in polarization and spatial-mode degrees of freedom. The construction of the photonic module in a photonic band-gap structure is presented, and the operation of the module is utilized to implement the photonic nondestructive parity checks on the two degrees of freedom. We first propose a hyperconcentration protocol using twomore » identical partially hyperentangled initial states with unknown coefficients to distill a maximally hyperentangled state probabilistically, and further propose a protocol by the assistance of an ancillary single photon prepared according to the known coefficients of the initial state. In the two protocols, the total success probability can be improved greatly by introducing the iteration mechanism, and only one of the remote parties is required to perform the parity checks in each round of iteration. Estimates on the system requirements and recent experimental results indicate that our proposal is realizable with existing or near-further technologies.« less

  1. A Trusted Third-Party E-Payment Protocol Based on Quantum Blind Signature Without Entanglement

    NASA Astrophysics Data System (ADS)

    Guo, Xi; Zhang, Jian-Zhong; Xie, Shu-Cui

    2018-06-01

    In this paper, we present a trusted third-party e-payment protocol which is designed based on quantum blind signature without entanglement. The security and verifiability of our scheme are guaranteed by using single-particle unitary operation, quantum key distribution (QKD) protocol and one-time pad. Furthermore, once there is a dispute among the participants, it can be solved with the assistance of the third-party platform which is reliant.

  2. Multi-party Semi-quantum Key Agreement with Delegating Quantum Computation

    NASA Astrophysics Data System (ADS)

    Liu, Wen-Jie; Chen, Zhen-Yu; Ji, Sai; Wang, Hai-Bin; Zhang, Jun

    2017-10-01

    A multi-party semi-quantum key agreement (SQKA) protocol based on delegating quantum computation (DQC) model is proposed by taking Bell states as quantum resources. In the proposed protocol, the participants only need the ability of accessing quantum channel and preparing single photons {|0〉, |1〉, |+〉, |-〉}, while the complicated quantum operations, such as the unitary operations and Bell measurement, will be delegated to the remote quantum center. Compared with previous quantum key agreement protocols, this client-server model is more feasible in the early days of the emergence of quantum computers. In order to prevent the attacks from outside eavesdroppers, inner participants and quantum center, two single photon sequences are randomly inserted into Bell states: the first sequence is used to perform the quantum channel detection, while the second is applied to disorder the positions of message qubits, which guarantees the security of the protocol.

  3. Quantum secret sharing with identity authentication based on Bell states

    NASA Astrophysics Data System (ADS)

    Abulkasim, Hussein; Hamad, Safwat; Khalifa, Amal; El Bahnasy, Khalid

    Quantum secret sharing techniques allow two parties or more to securely share a key, while the same number of parties or less can efficiently deduce the secret key. In this paper, we propose an authenticated quantum secret sharing protocol, where a quantum dialogue protocol is adopted to authenticate the identity of the parties. The participants simultaneously authenticate the identity of each other based on parts of a prior shared key. Moreover, the whole prior shared key can be reused for deducing the secret data. Although the proposed scheme does not significantly improve the efficiency performance, it is more secure compared to some existing quantum secret sharing scheme due to the identity authentication process. In addition, the proposed scheme can stand against participant attack, man-in-the-middle attack, impersonation attack, Trojan-horse attack as well as information leaks.

  4. Protocols development for security and privacy of radio frequency identification systems

    NASA Astrophysics Data System (ADS)

    Sabbagha, Fatin

    There are benefits to adopting radio frequency identification (RFID) technology, although there are methods of attack that can compromise the system. This research determined how that may happen and what possible solutions can keep that from happening. Protocols were developed to implement better security. In addition, new topologies were developed to handle the problems of the key management. Previously proposed protocols focused on providing mutual authentication and privacy between readers and tags. However, those protocols are still vulnerable to be attacked. These protocols were analyzed and the disadvantages shown for each one. Previous works assumed that the channels between readers and the servers were secure. In the proposed protocols, a compromised reader is considered along with how to prevent tags from being read by that reader. The new protocols provide mutual authentication between readers and tags and, at the same time, remove the compromised reader from the system. Three protocols are proposed. In the first protocol, a mutual authentication is achieved and a compromised reader is not allowed in the network. In the second protocol, the number of times a reader contacts the server is reduced. The third protocol provides authentication and privacy between tags and readers using a trusted third party. The developed topology is implemented using python language and simulates work to check the efficiency regarding the processing time. The three protocols are implemented by writing codes in C language and then compiling them in MSP430. IAR Embedded workbench is used, which is an integrated development environment with the C/C++ compiler to generate a faster code and to debug the microcontroller. In summary, the goal of this research is to find solutions for the problems on previously proposed protocols, handle a compromised reader, and solve key management problems.

  5. Experimental verification of multipartite entanglement in quantum networks

    PubMed Central

    McCutcheon, W.; Pappa, A.; Bell, B. A.; McMillan, A.; Chailloux, A.; Lawson, T.; Mafu, M.; Markham, D.; Diamanti, E.; Kerenidis, I.; Rarity, J. G.; Tame, M. S.

    2016-01-01

    Multipartite entangled states are a fundamental resource for a wide range of quantum information processing tasks. In particular, in quantum networks, it is essential for the parties involved to be able to verify if entanglement is present before they carry out a given distributed task. Here we design and experimentally demonstrate a protocol that allows any party in a network to check if a source is distributing a genuinely multipartite entangled state, even in the presence of untrusted parties. The protocol remains secure against dishonest behaviour of the source and other parties, including the use of system imperfections to their advantage. We demonstrate the verification protocol in a three- and four-party setting using polarization-entangled photons, highlighting its potential for realistic photonic quantum communication and networking applications. PMID:27827361

  6. Quantum discord bounds the amount of distributed entanglement.

    PubMed

    Chuan, T K; Maillard, J; Modi, K; Paterek, T; Paternostro, M; Piani, M

    2012-08-17

    The ability to distribute quantum entanglement is a prerequisite for many fundamental tests of quantum theory and numerous quantum information protocols. Two distant parties can increase the amount of entanglement between them by means of quantum communication encoded in a carrier that is sent from one party to the other. Intriguingly, entanglement can be increased even when the exchanged carrier is not entangled with the parties. However, in light of the defining property of entanglement stating that it cannot increase under classical communication, the carrier must be quantum. Here we show that, in general, the increase of relative entropy of entanglement between two remote parties is bounded by the amount of nonclassical correlations of the carrier with the parties as quantified by the relative entropy of discord. We study implications of this bound, provide new examples of entanglement distribution via unentangled states, and put further limits on this phenomenon.

  7. Controlled Bidirectional Hybrid of Remote State Preparation and Quantum Teleportation via Seven-Qubit Entangled State

    NASA Astrophysics Data System (ADS)

    Wu, Hao; Zha, Xin-Wei; Yang, Yu-Quan

    2018-01-01

    We propose a new protocol of implementing four-party controlled joint remote state preparation and meanwhile realizing controlled quantum teleportation via a seven-qubit entangled state. That is to say, Alice wants to teleport an arbitrary single-qubit state to Bob and Bob wants to remotely prepare a known state for Alice via the control of supervisors Fred and David. Compared with previous studies for the schemes of solely bidirectional quantum teleportation and remote state preparation, the new protocol is a kind of hybrid approach of information communication which makes the quantum channel multipurpose.

  8. Improving Continuous-Variable Measurement-Device-Independent Multipartite Quantum Communication with Optical Amplifiers*

    NASA Astrophysics Data System (ADS)

    Guo, Ying; Zhao, Wei; Li, Fei; Huang, Duan; Liao, Qin; Xie, Cai-Lang

    2017-08-01

    The developing tendency of continuous-variable (CV) measurement-device-independent (MDI) quantum cryptography is to cope with the practical issue of implementing scalable quantum networks. Up to now, most theoretical and experimental researches on CV-MDI QKD are focused on two-party protocols. However, we suggest a CV-MDI multipartite quantum secret sharing (QSS) protocol use the EPR states coupled with optical amplifiers. More remarkable, QSS is the real application in multipartite CV-MDI QKD, in other words, is the concrete implementation method of multipartite CV-MDI QKD. It can implement a practical quantum network scheme, under which the legal participants create the secret correlations by using EPR states connecting to an untrusted relay via insecure links and applying the multi-entangled Greenberger-Horne-Zeilinger (GHZ) state analysis at relay station. Even if there is a possibility that the relay may be completely tampered, the legal participants are still able to extract a secret key from network communication. The numerical simulation indicates that the quantum network communication can be achieved in an asymmetric scenario, fulfilling the demands of a practical quantum network. Additionally, we illustrate that the use of optical amplifiers can compensate the partial inherent imperfections of detectors and increase the transmission distance of the CV-MDI quantum system.

  9. Counterfactual Quantum Deterministic Key Distribution

    NASA Astrophysics Data System (ADS)

    Zhang, Sheng; Wang, Jian; Tang, Chao-Jing

    2013-01-01

    We propose a new counterfactual quantum cryptography protocol concerning about distributing a deterministic key. By adding a controlled blocking operation module to the original protocol [T.G. Noh, Phys. Rev. Lett. 103 (2009) 230501], the correlation between the polarizations of the two parties, Alice and Bob, is extended, therefore, one can distribute both deterministic keys and random ones using our protocol. We have also given a simple proof of the security of our protocol using the technique we ever applied to the original protocol. Most importantly, our analysis produces a bound tighter than the existing ones.

  10. 40 CFR 82.4 - Prohibitions for class I controlled substances.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... not listed as a Party to the 1987 Montreal Protocol unless that foreign state is complying with the 1987 Montreal Protocol (See appendix C, annex 2 of this subpart); (2) Import or export any quantity of... to this subpart, from any foreign state not Party to the 1987 Montreal Protocol (as noted in appendix...

  11. 40 CFR 82.4 - Prohibitions for class I controlled substances.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... not listed as a Party to the 1987 Montreal Protocol unless that foreign state is complying with the 1987 Montreal Protocol (See appendix C, annex 2 of this subpart); (2) Import or export any quantity of... to this subpart, from any foreign state not Party to the 1987 Montreal Protocol (as noted in appendix...

  12. Continuous-variable quantum cryptography with an untrusted relay: Detailed security analysis of the symmetric configuration

    NASA Astrophysics Data System (ADS)

    Ottaviani, Carlo; Spedalieri, Gaetana; Braunstein, Samuel L.; Pirandola, Stefano

    2015-02-01

    We consider the continuous-variable protocol of Pirandola et al. [arXiv:1312.4104] where the secret key is established by the measurement of an untrusted relay. In this network protocol, two authorized parties are connected to an untrusted relay by insecure quantum links. Secret correlations are generated by a continuous-variable Bell detection performed on incoming coherent states. In the present work we provide a detailed study of the symmetric configuration, where the relay is midway between the parties. We analyze symmetric eavesdropping strategies against the quantum links explicitly showing that, at fixed transmissivity and thermal noise, two-mode coherent attacks are optimal, manifestly outperforming one-mode collective attacks based on independent entangling cloners. Such an advantage is shown both in terms of security threshold and secret-key rate.

  13. A Third-Party E-payment Protocol Based on Quantum Multi-proxy Blind Signature

    NASA Astrophysics Data System (ADS)

    Niu, Xu-Feng; Zhang, Jian-Zhong; Xie, Shu-Cui; Chen, Bu-Qing

    2018-05-01

    A third-party E-payment protocol is presented in this paper. It is based on quantum multi-proxy blind signature. Adopting the techniques of quantum key distribution, one-time pad and quantum multi-proxy blind signature, our third-party E-payment system could protect user's anonymity as the traditional E-payment systems do, and also have unconditional security which the classical E-payment systems can not provide. Furthermore, compared with the existing quantum E-payment systems, the proposed system could support the E-payment which using the third-party platforms.

  14. Cryptanalysis and Improvements for the Quantum Private Comparison Protocol Using EPR Pairs

    NASA Astrophysics Data System (ADS)

    Wang, Cong; Xu, Gang; Yang, Yi-Xian

    2013-07-01

    In this paper, we carry out an in-depth analysis of the quantum private comparison (QPC) protocol with the semi-honest third party (TP). The security of QPC protocol using the EPR pairs is re-examined. Unfortunately, we find that TP can use the fake EPR pairs to steal all the secret information. Furthermore, we give two simple and feasible solutions to improve the original QPC protocol. It is shown that the improved protocol is secure, which can resist various kinds of attacks from both the outside eavesdroppers and the inside participants, even the semi-honest TP.

  15. Unconditional security of entanglement-based continuous-variable quantum secret sharing

    NASA Astrophysics Data System (ADS)

    Kogias, Ioannis; Xiang, Yu; He, Qiongyi; Adesso, Gerardo

    2017-01-01

    The need for secrecy and security is essential in communication. Secret sharing is a conventional protocol to distribute a secret message to a group of parties, who cannot access it individually but need to cooperate in order to decode it. While several variants of this protocol have been investigated, including realizations using quantum systems, the security of quantum secret sharing schemes still remains unproven almost two decades after their original conception. Here we establish an unconditional security proof for entanglement-based continuous-variable quantum secret sharing schemes, in the limit of asymptotic keys and for an arbitrary number of players. We tackle the problem by resorting to the recently developed one-sided device-independent approach to quantum key distribution. We demonstrate theoretically the feasibility of our scheme, which can be implemented by Gaussian states and homodyne measurements, with no need for ideal single-photon sources or quantum memories. Our results contribute to validating quantum secret sharing as a viable primitive for quantum technologies.

  16. Authenticated Quantum Key Distribution with Collective Detection using Single Photons

    NASA Astrophysics Data System (ADS)

    Huang, Wei; Xu, Bing-Jie; Duan, Ji-Tong; Liu, Bin; Su, Qi; He, Yuan-Hang; Jia, Heng-Yue

    2016-10-01

    We present two authenticated quantum key distribution (AQKD) protocols by utilizing the idea of collective (eavesdropping) detection. One is a two-party AQKD protocol, the other is a multiparty AQKD protocol with star network topology. In these protocols, the classical channels need not be assumed to be authenticated and the single photons are used as the quantum information carriers. To achieve mutual identity authentication and establish a random key in each of the proposed protocols, only one participant should be capable of preparing and measuring single photons, and the main quantum ability that the rest of the participants should have is just performing certain unitary operations. Security analysis shows that these protocols are free from various kinds of attacks, especially the impersonation attack and the man-in-the-middle (MITM) attack.

  17. Multi-party quantum key agreement with five-qubit brown states

    NASA Astrophysics Data System (ADS)

    Cai, Tao; Jiang, Min; Cao, Gang

    2018-05-01

    In this paper, we propose a multi-party quantum key agreement protocol with five-qubit brown states and single-qubit measurements. Our multi-party protocol ensures each participant to contribute equally to the agreement key. Each party performs three single-qubit unitary operations on three qubits of each brown state. Finally, by measuring brown states and decoding the measurement results, all participants can negotiate a shared secret key without classical bits exchange between them. With the analysis of security, our protocol demonstrates that it can resist against both outsider and participant attacks. Compared with other schemes, it also possesses a higher information efficiency. In terms of physical operation, it requires single-qubit measurements only which weakens the hardware requirements of participant and has a better operating flexibility.

  18. High-Dimensional Circular Quantum Secret Sharing Using Orbital Angular Momentum

    NASA Astrophysics Data System (ADS)

    Tang, Dawei; Wang, Tie-jun; Mi, Sichen; Geng, Xiao-Meng; Wang, Chuan

    2016-11-01

    Quantum secret sharing is to distribute secret message securely between multi-parties. Here exploiting orbital angular momentum (OAM) state of single photons as the information carrier, we propose a high-dimensional circular quantum secret sharing protocol which increases the channel capacity largely. In the proposed protocol, the secret message is split into two parts, and each encoded on the OAM state of single photons. The security of the protocol is guaranteed by the laws of non-cloning theorem. And the secret messages could not be recovered except that the two receivers collaborated with each other. Moreover, the proposed protocol could be extended into high-level quantum systems, and the enhanced security could be achieved.

  19. Funding Mechanisms for Ecosystem Services Projects

    NASA Astrophysics Data System (ADS)

    Russell, V.

    2014-12-01

    Ecosystem services projects ideally should be funded through commoditized markets. Where those markets do not exist financing directly from interested private sector parties can be a direct link between business interested in fulfilling sustainability goals and project implementers. Challenges exist, however in 1) linking those interests; 2) carefully quantifying the services produced, their true costs to implement and meeting protocol standards; 3) measuring the success of projects, especially over lengthy periods of time; and 4) balancing issues related to multiple spatial scales for projects and funding to make a difference. Examples from National Forest Foundation's experience implementing carbon and water projects with multiple private sector funders and the USDA Forest Service will highlight experiences and lessons learned in funding and implementing ecosystem service projects.

  20. Privacy-preserving public auditing for data integrity in cloud

    NASA Astrophysics Data System (ADS)

    Shaik Saleem, M.; Murali, M.

    2018-04-01

    Cloud computing which has collected extent concentration from communities of research and with industry research development, a large pool of computing resources using virtualized sharing method like storage, processing power, applications and services. The users of cloud are vend with on demand resources as they want in the cloud computing. Outsourced file of the cloud user can easily tampered as it is stored at the third party service providers databases, so there is no integrity of cloud users data as it has no control on their data, therefore providing security assurance to the users data has become one of the primary concern for the cloud service providers. Cloud servers are not responsible for any data loss as it doesn’t provide the security assurance to the cloud user data. Remote data integrity checking (RDIC) licenses an information to data storage server, to determine that it is really storing an owners data truthfully. RDIC is composed of security model and ID-based RDIC where it is responsible for the security of every server and make sure the data privacy of cloud user against the third party verifier. Generally, by running a two-party Remote data integrity checking (RDIC) protocol the clients would themselves be able to check the information trustworthiness of their cloud. Within the two party scenario the verifying result is given either from the information holder or the cloud server may be considered as one-sided. Public verifiability feature of RDIC gives the privilege to all its users to verify whether the original data is modified or not. To ensure the transparency of the publicly verifiable RDIC protocols, Let’s figure out there exists a TPA who is having knowledge and efficiency to verify the work to provide the condition clearly by publicly verifiable RDIC protocols.

  1. Super-dense teleportation for space applications

    NASA Astrophysics Data System (ADS)

    Zeitler, Chris; Graham, Trent M.; Chapman, Joseph; Bernstein, Herbert; Kwiat, Paul G.

    2016-03-01

    Establishing a quantum communication network would provide advantages in areas such as security and information processing. Such a network would require the implementation of quantum teleportation between remote parties. However, for photonic "qudits" of dimension greater than two, this teleportation always fails due to the inability to carry out the required quantum Bell-state measurement. A quantum communication protocol called Superdense Teleportation (SDT) can allow the reconstruction of a state without the usual 2-photon Bell-state measurements, enabling the protocol to succeed deterministically even for high dimensional qudits. This technique restricts the class of states transferred to equimodular states, a type of superposition state where each term can differ from the others in phase but not in amplitude; this restricted space of transmitted states allows the transfer to occur deterministically. We report on our implementation of SDT using photon pairs that are entangled in both polarization and temporal mode. After encoding the phases of the desired equimodular state on the signal photon, we perform a complete tomography on the idler photon to verify that we properly prepared the chosen state. Beyond our tabletop demonstration, we are working towards an implementation between a space platform in low earth orbit and a ground telescope, to demonstrate the feasibility of space-based quantum communication. We will discuss the various challenges presented by moving the experiment out of the laboratory, and our proposed solutions to make Superdense Teleportation realizable in the space setting.

  2. General A Scheme to Share Information via Employing Discrete Algorithm to Quantum States

    NASA Astrophysics Data System (ADS)

    Kang, Guo-Dong; Fang, Mao-Fa

    2011-02-01

    We propose a protocol for information sharing between two legitimate parties (Bob and Alice) via public-key cryptography. In particular, we specialize the protocol by employing discrete algorithm under mod that maps integers to quantum states via photon rotations. Based on this algorithm, we find that the protocol is secure under various classes of attacks. Specially, owe to the algorithm, the security of the classical privacy contained in the quantum public-key and the corresponding ciphertext is guaranteed. And the protocol is robust against the impersonation attack and the active wiretapping attack by designing particular checking processing, thus the protocol is valid.

  3. Two-dimensional distributed-phase-reference protocol for quantum key distribution

    NASA Astrophysics Data System (ADS)

    Bacco, Davide; Christensen, Jesper Bjerge; Castaneda, Mario A. Usuga; Ding, Yunhong; Forchhammer, Søren; Rottwitt, Karsten; Oxenløwe, Leif Katsuo

    2016-12-01

    Quantum key distribution (QKD) and quantum communication enable the secure exchange of information between remote parties. Currently, the distributed-phase-reference (DPR) protocols, which are based on weak coherent pulses, are among the most practical solutions for long-range QKD. During the last 10 years, long-distance fiber-based DPR systems have been successfully demonstrated, although fundamental obstacles such as intrinsic channel losses limit their performance. Here, we introduce the first two-dimensional DPR-QKD protocol in which information is encoded in the time and phase of weak coherent pulses. The ability of extracting two bits of information per detection event, enables a higher secret key rate in specific realistic network scenarios. Moreover, despite the use of more dimensions, the proposed protocol remains simple, practical, and fully integrable.

  4. Two-dimensional distributed-phase-reference protocol for quantum key distribution.

    PubMed

    Bacco, Davide; Christensen, Jesper Bjerge; Castaneda, Mario A Usuga; Ding, Yunhong; Forchhammer, Søren; Rottwitt, Karsten; Oxenløwe, Leif Katsuo

    2016-12-22

    Quantum key distribution (QKD) and quantum communication enable the secure exchange of information between remote parties. Currently, the distributed-phase-reference (DPR) protocols, which are based on weak coherent pulses, are among the most practical solutions for long-range QKD. During the last 10 years, long-distance fiber-based DPR systems have been successfully demonstrated, although fundamental obstacles such as intrinsic channel losses limit their performance. Here, we introduce the first two-dimensional DPR-QKD protocol in which information is encoded in the time and phase of weak coherent pulses. The ability of extracting two bits of information per detection event, enables a higher secret key rate in specific realistic network scenarios. Moreover, despite the use of more dimensions, the proposed protocol remains simple, practical, and fully integrable.

  5. Two-dimensional distributed-phase-reference protocol for quantum key distribution

    PubMed Central

    Bacco, Davide; Christensen, Jesper Bjerge; Castaneda, Mario A. Usuga; Ding, Yunhong; Forchhammer, Søren; Rottwitt, Karsten; Oxenløwe, Leif Katsuo

    2016-01-01

    Quantum key distribution (QKD) and quantum communication enable the secure exchange of information between remote parties. Currently, the distributed-phase-reference (DPR) protocols, which are based on weak coherent pulses, are among the most practical solutions for long-range QKD. During the last 10 years, long-distance fiber-based DPR systems have been successfully demonstrated, although fundamental obstacles such as intrinsic channel losses limit their performance. Here, we introduce the first two-dimensional DPR-QKD protocol in which information is encoded in the time and phase of weak coherent pulses. The ability of extracting two bits of information per detection event, enables a higher secret key rate in specific realistic network scenarios. Moreover, despite the use of more dimensions, the proposed protocol remains simple, practical, and fully integrable. PMID:28004821

  6. Analysis of Counterfactual Quantum Certificate Authorization

    NASA Astrophysics Data System (ADS)

    Wang, Tian-Yin; Li, Yan-Ping; Zhang, Rui-Ling

    2016-12-01

    A counterfactual quantum certificate authorization protocol was proposed recently (Shenoy et al., Phys. Rev. A 89, 052307 (20)), in which a trusted third party, Alice, authenticates an entity Bob (e.g., a bank) that a client Charlie wishes to securely transact with. However, this protocol requires a classical authenticated channel between Bob and Charlie to prevent possible attacks from the third party Alice, which is in conflict with the task of certificate authorization in the sense that Bob and Charlie can establish an unconditionally-secure key by a quantum key distribution protocol if there is a classical authenticated channel between them and hence securely transact with each other even without the assistance of the third party Alice.

  7. Efficient universal blind quantum computation.

    PubMed

    Giovannetti, Vittorio; Maccone, Lorenzo; Morimae, Tomoyuki; Rudolph, Terry G

    2013-12-06

    We give a cheat sensitive protocol for blind universal quantum computation that is efficient in terms of computational and communication resources: it allows one party to perform an arbitrary computation on a second party's quantum computer without revealing either which computation is performed, or its input and output. The first party's computational capabilities can be extremely limited: she must only be able to create and measure single-qubit superposition states. The second party is not required to use measurement-based quantum computation. The protocol requires the (optimal) exchange of O(Jlog2(N)) single-qubit states, where J is the computational depth and N is the number of qubits needed for the computation.

  8. Variable-bias coin tossing

    NASA Astrophysics Data System (ADS)

    Colbeck, Roger; Kent, Adrian

    2006-03-01

    Alice is a charismatic quantum cryptographer who believes her parties are unmissable; Bob is a (relatively) glamorous string theorist who believes he is an indispensable guest. To prevent possibly traumatic collisions of self-perception and reality, their social code requires that decisions about invitation or acceptance be made via a cryptographically secure variable-bias coin toss (VBCT). This generates a shared random bit by the toss of a coin whose bias is secretly chosen, within a stipulated range, by one of the parties; the other party learns only the random bit. Thus one party can secretly influence the outcome, while both can save face by blaming any negative decisions on bad luck. We describe here some cryptographic VBCT protocols whose security is guaranteed by quantum theory and the impossibility of superluminal signaling, setting our results in the context of a general discussion of secure two-party computation. We also briefly discuss other cryptographic applications of VBCT.

  9. Statistics attack on `quantum private comparison with a malicious third party' and its improvement

    NASA Astrophysics Data System (ADS)

    Gu, Jun; Ho, Chih-Yung; Hwang, Tzonelih

    2018-02-01

    Recently, Sun et al. (Quantum Inf Process:14:2125-2133, 2015) proposed a quantum private comparison protocol allowing two participants to compare the equality of their secrets via a malicious third party (TP). They designed an interesting trap comparison method to prevent the TP from knowing the final comparison result. However, this study shows that the malicious TP can use the statistics attack to reveal the comparison result. A simple modification is hence proposed to solve this problem.

  10. Witnessing entanglement without entanglement witness operators.

    PubMed

    Pezzè, Luca; Li, Yan; Li, Weidong; Smerzi, Augusto

    2016-10-11

    Quantum mechanics predicts the existence of correlations between composite systems that, although puzzling to our physical intuition, enable technologies not accessible in a classical world. Notwithstanding, there is still no efficient general method to theoretically quantify and experimentally detect entanglement of many qubits. Here we propose to detect entanglement by measuring the statistical response of a quantum system to an arbitrary nonlocal parametric evolution. We witness entanglement without relying on the tomographic reconstruction of the quantum state, or the realization of witness operators. The protocol requires two collective settings for any number of parties and is robust against noise and decoherence occurring after the implementation of the parametric transformation. To illustrate its user friendliness we demonstrate multipartite entanglement in different experiments with ions and photons by analyzing published data on fidelity visibilities and variances of collective observables.

  11. Memory attacks on device-independent quantum cryptography.

    PubMed

    Barrett, Jonathan; Colbeck, Roger; Kent, Adrian

    2013-01-04

    Device-independent quantum cryptographic schemes aim to guarantee security to users based only on the output statistics of any components used, and without the need to verify their internal functionality. Since this would protect users against untrustworthy or incompetent manufacturers, sabotage, or device degradation, this idea has excited much interest, and many device-independent schemes have been proposed. Here we identify a critical weakness of device-independent protocols that rely on public communication between secure laboratories. Untrusted devices may record their inputs and outputs and reveal information about them via publicly discussed outputs during later runs. Reusing devices thus compromises the security of a protocol and risks leaking secret data. Possible defenses include securely destroying or isolating used devices. However, these are costly and often impractical. We propose other more practical partial defenses as well as a new protocol structure for device-independent quantum key distribution that aims to achieve composable security in the case of two parties using a small number of devices to repeatedly share keys with each other (and no other party).

  12. Blind quantum computation with identity authentication

    NASA Astrophysics Data System (ADS)

    Li, Qin; Li, Zhulin; Chan, Wai Hong; Zhang, Shengyu; Liu, Chengdong

    2018-04-01

    Blind quantum computation (BQC) allows a client with relatively few quantum resources or poor quantum technologies to delegate his computational problem to a quantum server such that the client's input, output, and algorithm are kept private. However, all existing BQC protocols focus on correctness verification of quantum computation but neglect authentication of participants' identity which probably leads to man-in-the-middle attacks or denial-of-service attacks. In this work, we use quantum identification to overcome such two kinds of attack for BQC, which will be called QI-BQC. We propose two QI-BQC protocols based on a typical single-server BQC protocol and a double-server BQC protocol. The two protocols can ensure both data integrity and mutual identification between participants with the help of a third trusted party (TTP). In addition, an unjammable public channel between a client and a server which is indispensable in previous BQC protocols is unnecessary, although it is required between TTP and each participant at some instant. Furthermore, the method to achieve identity verification in the presented protocols is general and it can be applied to other similar BQC protocols.

  13. In Brief: Kyoto Protocol moves forward

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2004-10-01

    The Russian cabinet's 30 September endorsement of the Kyoto Protocol to the United Nations Framework Convention on Climate Change (UNFCCC) likely clears the way for the treaty's ratification by that country's parliament and for its entry into force. The protocol enters into force when not less than 55 Parties to the Convention, including industrialized countries (so called ``Annex I Parties'') which accounted in total for at least 55 % of the total carbon dioxide emissions for 1990 from that group, officially have agreed to the treaty.

  14. A Third-Party E-Payment Protocol Based on Quantum Group Blind Signature

    NASA Astrophysics Data System (ADS)

    Zhang, Jian-Zhong; Yang, Yuan-Yuan; Xie, Shu-Cui

    2017-09-01

    A third-party E-payment protocol based on quantum group blind signature is proposed in this paper. Our E-payment protocol could protect user's anonymity as the traditional E-payment systems do, and also have unconditional security which the classical E-payment systems can not provide. To achieve that, quantum key distribution, one-time pad and quantum group blind signature are adopted in our scheme. Furthermore, if there were a dispute, the manager Trent can identify who tells a lie.

  15. Minutiae Matching with Privacy Protection Based on the Combination of Garbled Circuit and Homomorphic Encryption

    PubMed Central

    Li, Mengxing; Zhao, Jian; Yang, Mei; Kang, Lijun; Wu, Lili

    2014-01-01

    Biometrics plays an important role in authentication applications since they are strongly linked to holders. With an increasing growth of e-commerce and e-government, one can expect that biometric-based authentication systems are possibly deployed over the open networks in the near future. However, due to its openness, the Internet poses a great challenge to the security and privacy of biometric authentication. Biometric data cannot be revoked, so it is of paramount importance that biometric data should be handled in a secure way. In this paper we present a scheme achieving privacy-preserving fingerprint authentication between two parties, in which fingerprint minutiae matching algorithm is completed in the encrypted domain. To improve the efficiency, we exploit homomorphic encryption as well as garbled circuits to design the protocol. Our goal is to provide protection for the security of template in storage and data privacy of two parties in transaction. The experimental results show that the proposed authentication protocol runs efficiently. Therefore, the protocol can run over open networks and help to alleviate the concerns on security and privacy of biometric applications over the open networks. PMID:24711729

  16. Minutiae matching with privacy protection based on the combination of garbled circuit and homomorphic encryption.

    PubMed

    Li, Mengxing; Feng, Quan; Zhao, Jian; Yang, Mei; Kang, Lijun; Wu, Lili

    2014-01-01

    Biometrics plays an important role in authentication applications since they are strongly linked to holders. With an increasing growth of e-commerce and e-government, one can expect that biometric-based authentication systems are possibly deployed over the open networks in the near future. However, due to its openness, the Internet poses a great challenge to the security and privacy of biometric authentication. Biometric data cannot be revoked, so it is of paramount importance that biometric data should be handled in a secure way. In this paper we present a scheme achieving privacy-preserving fingerprint authentication between two parties, in which fingerprint minutiae matching algorithm is completed in the encrypted domain. To improve the efficiency, we exploit homomorphic encryption as well as garbled circuits to design the protocol. Our goal is to provide protection for the security of template in storage and data privacy of two parties in transaction. The experimental results show that the proposed authentication protocol runs efficiently. Therefore, the protocol can run over open networks and help to alleviate the concerns on security and privacy of biometric applications over the open networks.

  17. Multi-project baselines for potential clean development mechanism projects in the electricity sector in South Africa

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Winkler, H.; Spalding-Fecher, R.; Sathaye, J.

    2002-06-26

    The United Nations Framework Convention on Climate Change (UNFCCC) aims to reduce emissions of greenhouse gases (GHGs) in order to ''prevent dangerous anthropogenic interference with the climate system'' and promote sustainable development. The Kyoto Protocol, which was adopted in 1997 and appears likely to be ratified by 2002 despite the US withdrawing, aims to provide means to achieve this objective. The Clean Development Mechanism (CDM) is one of three ''flexibility mechanisms'' in the Protocol, the other two being Joint Implementation (JI) and Emissions Trading (ET). These mechanisms allow flexibility for Annex I Parties (industrialized countries) to achieve reductions by extra-territorialmore » as well as domestic activities. The underlying concept is that trade and transfer of credits will allow emissions reductions at least cost. Since the atmosphere is a global, well-mixed system, it does not matter where greenhouse gas emissions are reduced. The CDM allows Annex I Parties to meet part of their emissions reductions targets by investing in developing countries. CDM projects must also meet the sustainable development objectives of the developing country. Further criteria are that Parties must participate voluntarily, that emissions reductions are ''real, measurable and long-term'', and that they are additional to those that would have occurred anyway. The last requirement makes it essential to define an accurate baseline. The remaining parts of section 1 outline the theory of baselines, emphasizing the balance needed between environmental integrity and reducing transaction costs. Section 2 develops an approach to multi-project baseline for the South African electricity sector, comparing primarily to near future capacity, but also considering recent plants. Five potential CDM projects are briefly characterized in section 3, and compared to the baseline in section 4. Section 5 concludes with a discussion of options and choices for South Africa regarding electricity sector baselines.« less

  18. Recyclable amplification for single-photon entanglement from photon loss and decoherence

    NASA Astrophysics Data System (ADS)

    Zhou, Lan; Chen, Ling-Quan; Zhong, Wei; Sheng, Yu-Bo

    2018-01-01

    We put forward a highly efficient recyclable single-photon assisted amplification protocol, which can protect single-photon entanglement (SPE) from photon loss and decoherence. Making use of quantum nondemolition detection gates constructed with the help of cross-Kerr nonlinearity, our protocol has some attractive advantages. First, the parties can recover less-entangled SPE to be maximally entangled SPE, and reduce photon loss simultaneously. Second, if the protocol fails, the parties can repeat the protocol to reuse some discarded items, which can increase the success probability. Third, when the protocol is successful, they can similarly repeat the protocol to further increase the fidelity of the SPE. Thereby, our protocol provides a possible way to obtain high entanglement, high fidelity and high success probability simultaneously. In particular, our protocol shows higher success probability in the practical high photon loss channel. Based on the above features, our amplification protocol has potential for future application in long-distance quantum communication.

  19. The general theory of three-party quantum secret sharing protocols over phase-damping channels

    NASA Astrophysics Data System (ADS)

    Song, Ting-Ting; Wen, Qiao-Yan; Qin, Su-Juan; Zhang, Wei-Wei; Sun, Ying

    2013-10-01

    The general theory of three-party QSS protocols with the noisy quantum channels is discussed. When the particles are transmitted through the noisy quantum channels, the initial pure three-qubit tripartite entangled states would be changed into mixed states. We analyze the security of QSS protocols with the different kinds of three-qubit tripartite entangled states under phase-damping channels and figure out, for different kinds of initial states, the successful probabilities that Alice's secret can be recovered by legal agents are different. Comparing with one recent QSS protocol based on GHZ states, our scheme is secure, and has a little smaller key rate than that of the recent protocol.

  20. Cryptography from noisy storage.

    PubMed

    Wehner, Stephanie; Schaffner, Christian; Terhal, Barbara M

    2008-06-06

    We show how to implement cryptographic primitives based on the realistic assumption that quantum storage of qubits is noisy. We thereby consider individual-storage attacks; i.e., the dishonest party attempts to store each incoming qubit separately. Our model is similar to the model of bounded-quantum storage; however, we consider an explicit noise model inspired by present-day technology. To illustrate the power of this new model, we show that a protocol for oblivious transfer is secure for any amount of quantum-storage noise, as long as honest players can perform perfect quantum operations. Our model also allows us to show the security of protocols that cope with noise in the operations of the honest players and achieve more advanced tasks such as secure identification.

  1. Bidirectional and Asymmetric Controlled Quantum Information Transmission via Five-qubit Brown State

    NASA Astrophysics Data System (ADS)

    Fang, Sheng-hui; Jiang, Min

    2017-05-01

    We put forward a new protocol of deterministic controlled bidirectional quantum information transmission, using a five-qubit Brown state. That is to say Alice wants to teleport an arbitrary single-qubit state to Bob and Bob wants to remotely prepare a known state for Alice via the control of the supervisor Charlie. In terms of physical implementations, only a CNOT gate, one Bell-state measurement and one qubit measurement are used in our protocol. Compared with previous study for solely bidirectional quantum teleportation and solely bidirectional remote state preparation schemes, our protocol is a kind of hybrid approach of information communication which makes the quantum channel multipurpose, i.e., no matter whether the transmitted state is known or unknown, the state information can be transmitted with each other via a five-qubit Brown state under the control of the third party as a supervisor.

  2. Comparative study of key exchange and authentication methods in application, transport and network level security mechanisms

    NASA Astrophysics Data System (ADS)

    Fathirad, Iraj; Devlin, John; Jiang, Frank

    2012-09-01

    The key-exchange and authentication are two crucial elements of any network security mechanism. IPsec, SSL/TLS, PGP and S/MIME are well-known security approaches in providing security service to network, transport and application layers; these protocols use different methods (based on their requirements) to establish keying materials and authenticates key-negotiation and participated parties. This paper studies and compares the authenticated key negotiation methods in mentioned protocols.

  3. Semiquantum key distribution with secure delegated quantum computation

    PubMed Central

    Li, Qin; Chan, Wai Hong; Zhang, Shengyu

    2016-01-01

    Semiquantum key distribution allows a quantum party to share a random key with a “classical” party who only can prepare and measure qubits in the computational basis or reorder some qubits when he has access to a quantum channel. In this work, we present a protocol where a secret key can be established between a quantum user and an almost classical user who only needs the quantum ability to access quantum channels, by securely delegating quantum computation to a quantum server. We show the proposed protocol is robust even when the delegated quantum server is a powerful adversary, and is experimentally feasible with current technology. As one party of our protocol is the most quantum-resource efficient, it can be more practical and significantly widen the applicability scope of quantum key distribution. PMID:26813384

  4. Practical single-photon-assisted remote state preparation with non-maximally entanglement

    NASA Astrophysics Data System (ADS)

    Wang, Dong; Huang, Ai-Jun; Sun, Wen-Yang; Shi, Jia-Dong; Ye, Liu

    2016-08-01

    Remote state preparation (RSP) and joint remote state preparation (JRSP) protocols for single-photon states are investigated via linear optical elements with partially entangled states. In our scheme, by choosing two-mode instances from a polarizing beam splitter, only the sender in the communication protocol needs to prepare an ancillary single-photon and operate the entanglement preparation process in order to retrieve an arbitrary single-photon state from a photon pair in partially entangled state. In the case of JRSP, i.e., a canonical model of RSP with multi-party, we consider that the information of the desired state is split into many subsets and in prior maintained by spatially separate parties. Specifically, with the assistance of a single-photon state and a three-photon entangled state, it turns out that an arbitrary single-photon state can be jointly and remotely prepared with certain probability, which is characterized by the coefficients of both the employed entangled state and the target state. Remarkably, our protocol is readily to extend to the case for RSP and JRSP of mixed states with the all optical means. Therefore, our protocol is promising for communicating among optics-based multi-node quantum networks.

  5. Deterministic entanglement distillation for secure double-server blind quantum computation.

    PubMed

    Sheng, Yu-Bo; Zhou, Lan

    2015-01-15

    Blind quantum computation (BQC) provides an efficient method for the client who does not have enough sophisticated technology and knowledge to perform universal quantum computation. The single-server BQC protocol requires the client to have some minimum quantum ability, while the double-server BQC protocol makes the client's device completely classical, resorting to the pure and clean Bell state shared by two servers. Here, we provide a deterministic entanglement distillation protocol in a practical noisy environment for the double-server BQC protocol. This protocol can get the pure maximally entangled Bell state. The success probability can reach 100% in principle. The distilled maximally entangled states can be remaind to perform the BQC protocol subsequently. The parties who perform the distillation protocol do not need to exchange the classical information and they learn nothing from the client. It makes this protocol unconditionally secure and suitable for the future BQC protocol.

  6. Deterministic entanglement distillation for secure double-server blind quantum computation

    PubMed Central

    Sheng, Yu-Bo; Zhou, Lan

    2015-01-01

    Blind quantum computation (BQC) provides an efficient method for the client who does not have enough sophisticated technology and knowledge to perform universal quantum computation. The single-server BQC protocol requires the client to have some minimum quantum ability, while the double-server BQC protocol makes the client's device completely classical, resorting to the pure and clean Bell state shared by two servers. Here, we provide a deterministic entanglement distillation protocol in a practical noisy environment for the double-server BQC protocol. This protocol can get the pure maximally entangled Bell state. The success probability can reach 100% in principle. The distilled maximally entangled states can be remaind to perform the BQC protocol subsequently. The parties who perform the distillation protocol do not need to exchange the classical information and they learn nothing from the client. It makes this protocol unconditionally secure and suitable for the future BQC protocol. PMID:25588565

  7. The BACnet Campus Challenge - Part 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Masica, Ken; Tom, Steve

    Here, the BACnet protocol was designed to achieve interoperability among building automation vendors and evolve over time to include new functionality as well as support new communication technologies such as the Ethernet and IP protocols as they became prevalent and economical in the market place. For large multi-building, multi-vendor campus environments, standardizing on the BACnet protocol as an implementation strategy can be a key component in meeting the challenge of an interoperable, flexible, and scalable building automation system. The interoperability of BACnet is especially important when large campuses with legacy equipment have DDC upgrades to facilities performed over different timemore » frames and use different contractors that install equipment from different vendors under the guidance of different campus HVAC project managers. In these circumstances, BACnet can serve as a common foundation for interoperability when potential variability exists in approaches to the design-build process by numerous parties over time. Likewise, BACnet support for a range of networking protocols and technologies can be a key strategy for achieving flexible and scalable automation systems as campuses and enterprises expand networking infrastructures using standard interoperable protocols like IP and Ethernet.« less

  8. The BACnet Campus Challenge - Part 1

    DOE PAGES

    Masica, Ken; Tom, Steve

    2015-12-01

    Here, the BACnet protocol was designed to achieve interoperability among building automation vendors and evolve over time to include new functionality as well as support new communication technologies such as the Ethernet and IP protocols as they became prevalent and economical in the market place. For large multi-building, multi-vendor campus environments, standardizing on the BACnet protocol as an implementation strategy can be a key component in meeting the challenge of an interoperable, flexible, and scalable building automation system. The interoperability of BACnet is especially important when large campuses with legacy equipment have DDC upgrades to facilities performed over different timemore » frames and use different contractors that install equipment from different vendors under the guidance of different campus HVAC project managers. In these circumstances, BACnet can serve as a common foundation for interoperability when potential variability exists in approaches to the design-build process by numerous parties over time. Likewise, BACnet support for a range of networking protocols and technologies can be a key strategy for achieving flexible and scalable automation systems as campuses and enterprises expand networking infrastructures using standard interoperable protocols like IP and Ethernet.« less

  9. Random bipartite entanglement from W and W-like states.

    PubMed

    Fortescue, Ben; Lo, Hoi-Kwong

    2007-06-29

    We describe a protocol for distilling maximally entangled bipartite states between random pairs of parties from those sharing a tripartite W state |W=(1/sqrt[3])(|100+|010+|001)(ABC), and show that the total distillation rate E(t)(infinity) [the total number of Einstein-Podolsky-Rosen (EPR) pairs distilled per W, irrespective of who shares them] may be done at a higher rate than EPR distillation between specified pairs of parties. Specifically, the optimal rate for distillation to specified parties has been previously shown to be 0.92 EPR pairs per W, while our protocol can asymptotically distill 1 EPR pair per W between random pairs of parties, which we conjecture to be optimal. We thus demonstrate a tradeoff between overall distillation rate and final distribution of EPR pairs. We further show that there exist states with fixed lower-bounded E(t)(infinity), but arbitrarily small distillable entanglement for specified parties.

  10. 40 CFR Appendix C to Subpart A of... - Parties to the Montreal Protocol, and Nations Complying With, But Not Parties to, the Protocol

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ✓ ✓ ✓ ✓ Slovakia ✓ ✓ ✓ ✓ ✓ Slovenia ✓ ✓ ✓ ✓ ✓ Solomon Island ✓ ✓ ✓ ✓ Somalia ✓ ✓ ✓ ✓ ✓ South Africa ✓ ✓ ✓ Spain... 118. Sierra Leone 119. Singapore 120. Solomon Islands 121. Somalia 122. South Africa 123. Sri Lanka...

  11. 40 CFR Appendix C to Subpart A of... - Parties to the Montreal Protocol, and Nations Complying With, But Not Parties to, the Protocol

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ✓ ✓ ✓ ✓ Slovakia ✓ ✓ ✓ ✓ ✓ Slovenia ✓ ✓ ✓ ✓ ✓ Solomon Island ✓ ✓ ✓ ✓ Somalia ✓ ✓ ✓ ✓ ✓ South Africa ✓ ✓ ✓ Spain... 118. Sierra Leone 119. Singapore 120. Solomon Islands 121. Somalia 122. South Africa 123. Sri Lanka...

  12. 40 CFR Appendix C to Subpart A of... - Parties to the Montreal Protocol, and Nations Complying With, But Not Parties to, the Protocol

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ✓ ✓ ✓ ✓ Slovakia ✓ ✓ ✓ ✓ ✓ Slovenia ✓ ✓ ✓ ✓ ✓ Solomon Island ✓ ✓ ✓ ✓ Somalia ✓ ✓ ✓ ✓ ✓ South Africa ✓ ✓ ✓ Spain... 118. Sierra Leone 119. Singapore 120. Solomon Islands 121. Somalia 122. South Africa 123. Sri Lanka...

  13. 40 CFR Appendix C to Subpart A of... - Parties to the Montreal Protocol, and Nations Complying With, But Not Parties to, the Protocol

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ✓ ✓ ✓ ✓ Slovakia ✓ ✓ ✓ ✓ ✓ Slovenia ✓ ✓ ✓ ✓ ✓ Solomon Island ✓ ✓ ✓ ✓ Somalia ✓ ✓ ✓ ✓ ✓ South Africa ✓ ✓ ✓ Spain... 118. Sierra Leone 119. Singapore 120. Solomon Islands 121. Somalia 122. South Africa 123. Sri Lanka...

  14. Witnessing entanglement without entanglement witness operators

    PubMed Central

    Pezzè, Luca; Li, Yan; Li, Weidong; Smerzi, Augusto

    2016-01-01

    Quantum mechanics predicts the existence of correlations between composite systems that, although puzzling to our physical intuition, enable technologies not accessible in a classical world. Notwithstanding, there is still no efficient general method to theoretically quantify and experimentally detect entanglement of many qubits. Here we propose to detect entanglement by measuring the statistical response of a quantum system to an arbitrary nonlocal parametric evolution. We witness entanglement without relying on the tomographic reconstruction of the quantum state, or the realization of witness operators. The protocol requires two collective settings for any number of parties and is robust against noise and decoherence occurring after the implementation of the parametric transformation. To illustrate its user friendliness we demonstrate multipartite entanglement in different experiments with ions and photons by analyzing published data on fidelity visibilities and variances of collective observables. PMID:27681625

  15. Secure and Robust Transmission and Verification of Unknown Quantum States in Minkowski Space

    PubMed Central

    Kent, Adrian; Massar, Serge; Silman, Jonathan

    2014-01-01

    An important class of cryptographic applications of relativistic quantum information work as follows. B generates a random qudit and supplies it to A at point P. A is supposed to transmit it at near light speed c to to one of a number of possible pairwise spacelike separated points Q1, …, Qn. A's transmission is supposed to be secure, in the sense that B cannot tell in advance which Qj will be chosen. This poses significant practical challenges, since secure reliable long-range transmission of quantum data at speeds near to c is presently not easy. Here we propose different techniques to overcome these diffculties. We introduce protocols that allow secure long-range implementations even when both parties control only widely separated laboratories of small size. In particular we introduce a protocol in which A needs send the qudit only over a short distance, and securely transmits classical information (for instance using a one time pad) over the remaining distance. We further show that by using parallel implementations of the protocols security can be maintained in the presence of moderate amounts of losses and errors. PMID:24469425

  16. Quantum key distribution with finite resources: Secret key rates via Renyi entropies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abruzzo, Silvestre; Kampermann, Hermann; Mertz, Markus

    A realistic quantum key distribution (QKD) protocol necessarily deals with finite resources, such as the number of signals exchanged by the two parties. We derive a bound on the secret key rate which is expressed as an optimization problem over Renyi entropies. Under the assumption of collective attacks by an eavesdropper, a computable estimate of our bound for the six-state protocol is provided. This bound leads to improved key rates in comparison to previous results.

  17. Robust quantum network architectures and topologies for entanglement distribution

    NASA Astrophysics Data System (ADS)

    Das, Siddhartha; Khatri, Sumeet; Dowling, Jonathan P.

    2018-01-01

    Entanglement distribution is a prerequisite for several important quantum information processing and computing tasks, such as quantum teleportation, quantum key distribution, and distributed quantum computing. In this work, we focus on two-dimensional quantum networks based on optical quantum technologies using dual-rail photonic qubits for the building of a fail-safe quantum internet. We lay out a quantum network architecture for entanglement distribution between distant parties using a Bravais lattice topology, with the technological constraint that quantum repeaters equipped with quantum memories are not easily accessible. We provide a robust protocol for simultaneous entanglement distribution between two distant groups of parties on this network. We also discuss a memory-based quantum network architecture that can be implemented on networks with an arbitrary topology. We examine networks with bow-tie lattice and Archimedean lattice topologies and use percolation theory to quantify the robustness of the networks. In particular, we provide figures of merit on the loss parameter of the optical medium that depend only on the topology of the network and quantify the robustness of the network against intermittent photon loss and intermittent failure of nodes. These figures of merit can be used to compare the robustness of different network topologies in order to determine the best topology in a given real-world scenario, which is critical in the realization of the quantum internet.

  18. Robust relativistic bit commitment

    NASA Astrophysics Data System (ADS)

    Chakraborty, Kaushik; Chailloux, André; Leverrier, Anthony

    2016-12-01

    Relativistic cryptography exploits the fact that no information can travel faster than the speed of light in order to obtain security guarantees that cannot be achieved from the laws of quantum mechanics alone. Recently, Lunghi et al. [Phys. Rev. Lett. 115, 030502 (2015), 10.1103/PhysRevLett.115.030502] presented a bit-commitment scheme where each party uses two agents that exchange classical information in a synchronized fashion, and that is both hiding and binding. A caveat is that the commitment time is intrinsically limited by the spatial configuration of the players, and increasing this time requires the agents to exchange messages during the whole duration of the protocol. While such a solution remains computationally attractive, its practicality is severely limited in realistic settings since all communication must remain perfectly synchronized at all times. In this work, we introduce a robust protocol for relativistic bit commitment that tolerates failures of the classical communication network. This is done by adding a third agent to both parties. Our scheme provides a quadratic improvement in terms of expected sustain time compared with the original protocol, while retaining the same level of security.

  19. PPLN-waveguide-based polarization entangled QKD simulator

    NASA Astrophysics Data System (ADS)

    Gariano, John; Djordjevic, Ivan B.

    2017-08-01

    We have developed a comprehensive simulator to study the polarization entangled quantum key distribution (QKD) system, which takes various imperfections into account. We assume that a type-II SPDC source using a PPLN-based nonlinear optical waveguide is used to generate entangled photon pairs and implements the BB84 protocol, using two mutually unbiased basis with two orthogonal polarizations in each basis. The entangled photon pairs are then simulated to be transmitted to both parties; Alice and Bob, through the optical channel, imperfect optical elements and onto the imperfect detector. It is assumed that Eve has no control over the detectors, and can only gain information from the public channel and the intercept resend attack. The secure key rate (SKR) is calculated using an upper bound and by using actual code rates of LDPC codes implementable in FPGA hardware. After the verification of the simulation results, such as the pair generation rate and the number of error due to multiple pairs, for the ideal scenario, available in the literature, we then introduce various imperfections. Then, the results are compared to previously reported experimental results where a BBO nonlinear crystal is used, and the improvements in SKRs are determined for when a PPLN-waveguide is used instead.

  20. Two-way QKD with single-photon-added coherent states

    NASA Astrophysics Data System (ADS)

    Miranda, Mario; Mundarain, Douglas

    2017-12-01

    In this work we present a two-way quantum key distribution (QKD) scheme that uses single-photon-added coherent states and displacement operations. The first party randomly sends coherent states (CS) or single-photon-added coherent states (SPACS) to the second party. The latter sends back the same state it received. Both parties decide which kind of states they are receiving by detecting or not a photon on the received signal after displacement operations. The first party must determine whether its sent and received states are equal; otherwise, the case must be discarded. We are going to show that an eavesdropper provided with a beam splitter gets the same information in any of the non-discarded cases. The key can be obtained by assigning 0 to CS and 1 to SPACS in the non-discarded cases. This protocol guarantees keys' security in the presence of a beam splitter attack even for states with a high number of photons in the sent signal. It also works in a lossy quantum channel, becoming a good bet for improving long-distance QKD.

  1. Quantum Authencryption with Two-Photon Entangled States for Off-Line Communicants

    NASA Astrophysics Data System (ADS)

    Ye, Tian-Yu

    2016-02-01

    In this paper, a quantum authencryption protocol is proposed by using the two-photon entangled states as the quantum resource. Two communicants Alice and Bob share two private keys in advance, which determine the generation of two-photon entangled states. The sender Alice sends the two-photon entangled state sequence encoded with her classical bits to the receiver Bob in the manner of one-step quantum transmission. Upon receiving the encoded quantum state sequence, Bob decodes out Alice's classical bits with the two-photon joint measurements and authenticates the integrity of Alice's secret with the help of one-way hash function. The proposed protocol only uses the one-step quantum transmission and needs neither a public discussion nor a trusted third party. As a result, the proposed protocol can be adapted to the case where the receiver is off-line, such as the quantum E-mail systems. Moreover, the proposed protocol provides the message authentication to one bit level with the help of one-way hash function and has an information-theoretical efficiency equal to 100 %.

  2. Protection of Cultural Heritage in Urban Areas during Peace and Conflict Times from Threats to Risk Preparedness as a Shared Responsibility

    NASA Astrophysics Data System (ADS)

    Cimino, C.

    2013-07-01

    In times of economic hardship, the support given by specialized civil society organisations to public institutions in the protection of cultural heritage has often proved very useful, and there is evidence that their contribution is essential in times of conflicts and natural disasters, if well-designed plans and measures are organized efficiently, thoroughly tested and properly implemented. The 1954 Hague Convention for the Protection of Cultural Property in the Event of Armed Conflict (HC), its two Protocols and other international juridical instruments address these situations since decades, however, they remained widely not-applied in absence of proper regulatory instruments. In 2004, the Second Protocol of the Hague Convention (1999HP) entered into force and the Committee of the State Parties was formed. It became clear that a new trend started when, in 2009, draft Guidelines for the implementation of the 1999HP were issued. Meanwhile, WATCH, in partnership with the Council of the United Municipalitities of Jbail (Lebanon) and the Head of the Municipality of Mtskheta (Georgia) prepared a project proposal aimed to set a precedent in the governance of urban sites that are registered in the World Heritage List which are at risk of armed conflict. The project War Free World Heritage Listed Cities http://www.warfreeheritage.net/ was co-financed in 2010 with a grant within the framework of the EC CIUDAD programme and it is currently at an advanced level of implementation. This presentation will focus on achievements and contingencies faced during implementation as well as lessons learned that could be surely useful for pers pective applicants.

  3. Investigation into Practical Implementations of a Zero Knowledge Protocol.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Marleau, Peter; Krentz-Wee, Rebecca E.

    In recent years, the concept of Zero Knowledge Protocols (ZKP) as a useful approach to nuclear warhead verification has become increasingly popular. Several implementations of ZKP have been proposed, driving technology development toward proof of concept demonstrations. Whereas proposed implementations seem to fall within the general class of template-based techniques, all physical implementations of ZKPs proposed to date have a complication: once the instrumentation is prepared, it is no longer authenticatable; the instrument physically contains sensitive information. In this work we explore three different concepts that may offer more authenticatable and practical ZKP implementations and evaluate the sensitive information thatmore » may be at risk when doing so: sharing a subset of detector counts in a preloaded image (with spatial information removed), real-time image subtraction, and a new concept, CONfirmation using a Fast-neutron Imaging Detector with Anti-image NULL-positive Time Encoding (CONFIDANTE). CONFIDANTE promises to offer an almost ideal implementation of ZKP: a positive result is indicated by a constant rate at all times enabling the monitoring party the possibility of full access to the instrument before, during, and after confirmation. A prototype of CONFIDANTE was designed, built, and its performance evaluated in a series of measurements of several objects including a set of plutonium dioxide Hemispheres. Very encouraging results proving feasibility are presented. 1 Rebecca is currently a graduate student in Nuclear Engineering at UC Berkeley« less

  4. Higher-dimensional communication complexity problems: Classical protocols versus quantum ones based on Bell's theorem or prepare-transmit-measure schemes

    NASA Astrophysics Data System (ADS)

    Tavakoli, Armin; Żukowski, Marek

    2017-04-01

    Communication complexity problems (CCPs) are tasks in which separated parties attempt to compute a function whose inputs are distributed among the parties. Their communication is limited so that not all inputs can be sent. We show that broad classes of Bell inequalities can be mapped to CCPs and that a quantum violation of a Bell inequality is a necessary and sufficient condition for an enhancement of the related CCP beyond its classical limitation. However, one can implement CCPs by transmitting a quantum system, encoding no more information than is allowed in the CCP, and extracting information by performing measurements. We show that for a large class of Bell inequalities, the improvement of the CCP associated with a quantum violation of a Bell inequality can be no greater than the improvement obtained from quantum prepare-transmit-measure strategies.

  5. The dilemma of "to be or not to be": developing electronically e-health & cloud computing documents for overseas transplant patients from Taiwan organ transplant health professionals' perspective.

    PubMed

    Shih, F-J; Fan, Y-W; Chiu, C-M; Shih, F-Ji; Wang, S-S

    2012-05-01

    The development of mutually accessible e-health documents (ehD) and cloud computing (CC) for overseas organ transplant health professionals (OTHP) in two medical parties (domestic and overseas) would ensure better quality of care. This project attempted to compare pro and con arguments from the perspective of Taiwan's OTHP. A sample was obtained from three leading medical centers in Taiwan. Eighty subjects including transplant surgeons (n = 20), registered nurses (RN; n = 30), coordinating nurses (OTCN; n = 15), and e-health information and communication technologies experts (ehICTs; n = 15) participated in this research. The pros of developing ehD were: (1) better and continuous care through communication and cooperation in two parties (78%); (2) better collaborative efforts between health professionals, information technology experts in two medical parties is (74%); (3) easier retrieval and communication of personal health documents with the trustworthy OTHP in the different countries (71%); and (4) CC may help develop transplant patients medical cloud based on the collaboration between medical systems in political parties of Taiwan and mainland China (69%). The cons of developing ehD and CC included: (1) inadequate knowledge of benefits and manuals of developing ehD and CC (75%); (2) no reliable communication avenues in developing ehD and CC (73%); (3) increased workload in direct care and documentation in developing new ehD and CC (70%); (4) lack of coaching and accreditation systems in medical, electronic, and law aspects to settle discrepancies in medical diagnosis and treatment protocols between two parties (68%); and (5) lacking systematic ehD and CC plans developed by interdisciplinary teams in two parties (60%). In this initial phase, the establishment of an interdisciplinary team including transplant leaders, transplant surgeon, RN, OTCN, ehICTs, and law experts from two parties might be helpful in working out developing plans with careful monitoring mechanisms. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. 75 FR 61485 - Regulatory Training Session With Air Carriers, EPA Regional Partners and Other Interested Parties...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-05

    ... Regional Partners and Other Interested Parties for Implementation of the Aircraft Drinking Water Rule... Agency (EPA) will hold a two-day training session on the regulatory requirements of the Aircraft Drinking... water systems'' under the Safe Drinking Water Act (SDWA) must meet the first set of requirements of the...

  7. Multiparty quantum key agreement with single particles

    NASA Astrophysics Data System (ADS)

    Liu, Bin; Gao, Fei; Huang, Wei; Wen, Qiao-yan

    2013-04-01

    Two conditions must be satisfied in a secure quantum key agreement (QKA) protocol: (1) outside eavesdroppers cannot gain the generated key without introducing any error; (2) the generated key cannot be determined by any non-trivial subset of the participants. That is, a secure QKA protocol can not only prevent the outside attackers from stealing the key, but also resist the attack from inside participants, i.e. some dishonest participants determine the key alone by illegal means. How to resist participant attack is an aporia in the design of QKA protocols, especially the multi-party ones. In this paper we present the first secure multiparty QKA protocol against both outside and participant attacks. Further more, we have proved its security in detail.

  8. Integrated quantum key distribution sender unit for daily-life implementations

    NASA Astrophysics Data System (ADS)

    Mélen, Gwenaelle; Vogl, Tobias; Rau, Markus; Corrielli, Giacomo; Crespi, Andrea; Osellame, Roberto; Weinfurter, Harald

    2016-03-01

    Unlike currently implemented encryption schemes, Quantum Key Distribution provides a secure way of generating and distributing a key among two parties. Although a multitude of research platforms has been developed, the integration of QKD units within classical communication systems remains a tremendous challenge. The recently achieved maturity of integrated photonic technologies could be exploited to create miniature QKD add-ons that could extend the primary function of various existing systems such as mobile devices or optical stations. In this work we report on an integrated optics module enabling secure short-distance communication for, e.g., quantum access schemes. Using BB84-like protocols, Alice's mobile low-cost device can exchange secure key and information everywhere within a trusted node network. The new optics platform (35×20×8mm) compatible with current smartphone's technology generates NIR faint polarised laser pulses with 100MHz repetition rate. Fully automated beam tracking and live basis-alignment on Bob's side ensure user-friendly operation with a quantum link efficiency as high as 50% stable over a few seconds.

  9. Continuous-variable quantum key distribution in uniform fast-fading channels

    NASA Astrophysics Data System (ADS)

    Papanastasiou, Panagiotis; Weedbrook, Christian; Pirandola, Stefano

    2018-03-01

    We investigate the performance of several continuous-variable quantum key distribution protocols in the presence of uniform fading channels. These are lossy channels whose transmissivity changes according to a uniform probability distribution. We assume the worst-case scenario where an eavesdropper induces a fast-fading process, where she chooses the instantaneous transmissivity while the remote parties may only detect the mean statistical effect. We analyze coherent-state protocols in various configurations, including the one-way switching protocol in reverse reconciliation, the measurement-device-independent protocol in the symmetric configuration, and its extension to a three-party network. We show that, regardless of the advantage given to the eavesdropper (control of the fading), these protocols can still achieve high rates under realistic attacks, within reasonable values for the variance of the probability distribution associated with the fading process.

  10. Quantum key distribution session with 16-dimensional photonic states.

    PubMed

    Etcheverry, S; Cañas, G; Gómez, E S; Nogueira, W A T; Saavedra, C; Xavier, G B; Lima, G

    2013-01-01

    The secure transfer of information is an important problem in modern telecommunications. Quantum key distribution (QKD) provides a solution to this problem by using individual quantum systems to generate correlated bits between remote parties, that can be used to extract a secret key. QKD with D-dimensional quantum channels provides security advantages that grow with increasing D. However, the vast majority of QKD implementations has been restricted to two dimensions. Here we demonstrate the feasibility of using higher dimensions for real-world quantum cryptography by performing, for the first time, a fully automated QKD session based on the BB84 protocol with 16-dimensional quantum states. Information is encoded in the single-photon transverse momentum and the required states are dynamically generated with programmable spatial light modulators. Our setup paves the way for future developments in the field of experimental high-dimensional QKD.

  11. Quantum key distribution session with 16-dimensional photonic states

    NASA Astrophysics Data System (ADS)

    Etcheverry, S.; Cañas, G.; Gómez, E. S.; Nogueira, W. A. T.; Saavedra, C.; Xavier, G. B.; Lima, G.

    2013-07-01

    The secure transfer of information is an important problem in modern telecommunications. Quantum key distribution (QKD) provides a solution to this problem by using individual quantum systems to generate correlated bits between remote parties, that can be used to extract a secret key. QKD with D-dimensional quantum channels provides security advantages that grow with increasing D. However, the vast majority of QKD implementations has been restricted to two dimensions. Here we demonstrate the feasibility of using higher dimensions for real-world quantum cryptography by performing, for the first time, a fully automated QKD session based on the BB84 protocol with 16-dimensional quantum states. Information is encoded in the single-photon transverse momentum and the required states are dynamically generated with programmable spatial light modulators. Our setup paves the way for future developments in the field of experimental high-dimensional QKD.

  12. Quantum key distribution session with 16-dimensional photonic states

    PubMed Central

    Etcheverry, S.; Cañas, G.; Gómez, E. S.; Nogueira, W. A. T.; Saavedra, C.; Xavier, G. B.; Lima, G.

    2013-01-01

    The secure transfer of information is an important problem in modern telecommunications. Quantum key distribution (QKD) provides a solution to this problem by using individual quantum systems to generate correlated bits between remote parties, that can be used to extract a secret key. QKD with D-dimensional quantum channels provides security advantages that grow with increasing D. However, the vast majority of QKD implementations has been restricted to two dimensions. Here we demonstrate the feasibility of using higher dimensions for real-world quantum cryptography by performing, for the first time, a fully automated QKD session based on the BB84 protocol with 16-dimensional quantum states. Information is encoded in the single-photon transverse momentum and the required states are dynamically generated with programmable spatial light modulators. Our setup paves the way for future developments in the field of experimental high-dimensional QKD. PMID:23897033

  13. Quantum dice rolling: a multi-outcome generalization of quantum coin flipping

    NASA Astrophysics Data System (ADS)

    Aharon, N.; Silman, J.

    2010-03-01

    The problem of quantum dice rolling (DR)—a generalization of the problem of quantum coin flipping (CF) to more than two outcomes and parties—is studied in both its weak and strong variants. We prove by construction that quantum mechanics allows for (i) weak N-sided DR admitting arbitrarily small bias for any N and (ii) two-party strong N-sided DR saturating Kitaev's bound for any N. To derive (ii) we also prove by construction that quantum mechanics allows for (iii) strong imbalanced CF saturating Kitaev's bound for any degree of imbalance. Furthermore, as a corollary of (ii) we introduce a family of optimal 2m-party strong nm-sided DR protocols for any pair m and n.

  14. 40 CFR 82.4 - Prohibitions for class I controlled substances.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... not Party to the 1987 Montreal Protocol unless that foreign state is complying with the 1987 Montreal Protocol (For ratification status, see: http://ozone.unep.org/new_site/en/treaty_ratification_status.php... Montreal Protocol, unless that foreign state is complying with the 1987 Montreal Protocol (For ratification...

  15. Strong Password-Based Authentication in TLS Using the Three-PartyGroup Diffie-Hellman Protocol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abdalla, Michel; Bresson, Emmanuel; Chevassut, Olivier

    2006-08-26

    The Internet has evolved into a very hostile ecosystem where"phishing'' attacks are common practice. This paper shows that thethree-party group Diffie-Hellman key exchange can help protect againstthese attacks. We have developed a suite of password-based cipher suitesfor the Transport Layer Security (TLS) protocol that are not onlyprovably secure but also assumed to be free from patent and licensingrestrictions based on an analysis of relevant patents in thearea.

  16. Quantum teleportation and information splitting via four-qubit cluster state and a Bell state

    NASA Astrophysics Data System (ADS)

    Ramírez, Marlon David González; Falaye, Babatunde James; Sun, Guo-Hua; Cruz-Irisson, M.; Dong, Shi-Hai

    2017-10-01

    Quantum teleportation provides a "bodiless" way of transmitting the quantum state from one object to another, at a distant location, using a classical communication channel and a previously shared entangled state. In this paper, we present a tripartite scheme for probabilistic teleportation of an arbitrary single qubit state, without losing the information of the state being teleported, via a fourqubit cluster state of the form | ϕ>1234 = α|0000>+ β|1010>+ γ|0101>- η|1111>, as the quantum channel, where the nonzero real numbers α, β, γ, and η satisfy the relation j αj2 + | β|2 + | γ|2 + | η|2 = 1. With the introduction of an auxiliary qubit with state |0>, using a suitable unitary transformation and a positive-operator valued measure (POVM), the receiver can recreate the state of the original qubit. An important advantage of the teleportation scheme demonstrated here is that, if the teleportation fails, it can be repeated without teleporting copies of the unknown quantum state, if the concerned parties share another pair of entangled qubit. We also present a protocol for quantum information splitting of an arbitrary two-particle system via the aforementioned cluster state and a Bell-state as the quantum channel. Problems related to security attacks were examined for both the cases and it was found that this protocol is secure. This protocol is highly efficient and easy to implement.

  17. Controlling corporate influence in health policy making? An assessment of the implementation of article 5.3 of the World Health Organization framework convention on tobacco control.

    PubMed

    Fooks, Gary Jonas; Smith, Julia; Lee, Kelley; Holden, Chris

    2017-03-08

    The World Health Organization (WHO) Framework Convention on Tobacco Control (FCTC) stands to significantly reduce tobacco-related mortality by accelerating the introduction of evidence-based tobacco control measures. However, the extent to which States Parties have implemented the Convention varies considerably. Article 5.3 of the FCTC, is intended to insulate policy-making from the tobacco industry's political influence, and aims to address barriers to strong implementation of the Convention associated with tobacco industry political activity. This paper quantitatively assesses implementation of Article 5.3's Guidelines for Implementation, evaluates the strength of Parties' efforts to implement specific recommendations, and explores how different approaches to implementation expose the policy process to continuing industry influence. We cross-referenced a broad range of documentary data (including FCTC Party reports and World Bank data on the governance of conflicts of interest in public administration) against Article 5.3 implementation guidelines (n = 24) for 155 Parties, and performed an in-depth thematic analysis to examine the strength of implementation for specific recommendations. Across all Parties, 16% of guideline recommendations reviewed have been implemented. Eighty-three percent of Parties that have taken some action under Article 5.3 have introduced less than a third of the guidelines. Most compliance with the guidelines is achieved through pre-existing policy instruments introduced independently of the FCTC, which rarely cover all relevant policy actors and fall short of the guideline recommendations. Measures introduced in response to the FCTC are typically restricted to health ministries and not explicit about third parties acting on behalf of the industry. Parties systematically overlook recommendations that facilitate industry monitoring. Highly selective and incomplete implementation of specific guideline recommendations facilitates extensive ongoing opportunities for industry policy influence. Stronger commitment to implementation is required to ensure consistently strong compliance with the FCTC internationally.

  18. New Evaluation of the Electronically Activated Recorder (EAR): Obtrusiveness, Compliance, and Participant Self-selection Effects.

    PubMed

    Manson, Joseph H; Robbins, Megan L

    2017-01-01

    The Electronically Activated Recorder (EAR) is a method for collecting periodic brief audio snippets of participants' daily lives using a portable recording device. The EAR can potentially intrude into people's privacy, alter their natural behavior, and introduce self-selection biases greater than in other types of social science methods. Previous research (Mehl and Holleran, 2007, hereafter M&H) has shown that participant non-compliance with, and perceived obtrusiveness of, an EAR protocol are both low. However, these questions have not been addressed in jurisdictions that require the consent of all parties to recording conversations. This EAR study required participants to wear a button bearing a microphone icon and the words "This conversation may be recorded" to comply with California's all-party consent law. Results revealed self-reported obtrusiveness and non-compliance were actually lower in the present study than in the M&H study. Behaviorally assessed non-compliance did not differ between the two studies. Participants in the present study talked more about being in the study than participants in the M&H study, but such talk still comprised <2% of sampled conversations. Another potential problem with the EAR, participant self-selection bias, was addressed by comparing the EAR volunteers' HEXACO personality dimensions to a non-volunteer sample drawn from the same student population. EAR volunteers were significantly and moderately higher in Conscientiousness, and lower in Emotionality, than non-volunteers. In conclusion, the EAR method can be successfully implemented in at least one all-party consent state (California). Interested researchers are encouraged to review this procedure with their own legal counsel.

  19. The prevention access and risk taking in young people (PARTY) project protocol: a cluster randomised controlled trial of health risk screening and motivational interviewing for young people presenting to general practice.

    PubMed

    Sanci, Lena; Grabsch, Brenda; Chondros, Patty; Shiell, Alan; Pirkis, Jane; Sawyer, Susan; Hegarty, Kelsey; Patterson, Elizabeth; Cahill, Helen; Ozer, Elizabeth; Seymour, Janelle; Patton, George

    2012-06-06

    There are growing worldwide concerns about the ability of primary health care systems to manage the major burden of illness in young people. Over two thirds of premature adult deaths result from risks that manifest in adolescence, including injury, neuropsychiatric problems and consequences of risky behaviours. One policy response is to better reorientate primary health services towards prevention and early intervention. Currently, however, there is insufficient evidence to support this recommendation for young people. This paper describes the design and implementation of a trial testing an intervention to promote psychosocial risk screening of all young people attending general practice and to respond to identified risks using motivational interviewing. clinicians' detection of risk-taking and emotional distress, young people's intention to change and reduction of risk taking. pathways to care, trust in the clinician and likelihood of returning for future visits. The design of the economic and process evaluation are not detailed in this protocol. PARTY is a cluster randomised trial recruiting 42 general practices in Victoria, Australia. Baseline measures include: youth friendly practice characteristics; practice staff's self-perceived competency in young people's care and clinicians' detection and response to risk taking behaviours and emotional distress in 14-24 year olds, attending the practice. Practices are then stratified by a social disadvantage index and billing methods and randomised. Intervention practices receive: nine hours of training and tools; feedback of their baseline data and two practice visits over six weeks. Comparison practices receive a three hour seminar in youth friendly practice only. Six weeks post-intervention, 30 consecutive young people are interviewed post-consultation from each practice and followed-up for self-reported risk taking behaviour and emotional distress three and 12 months post consultation. The PARTY trial is the first to examine the effectiveness and efficiency of a psychosocial risk screening and counselling intervention for young people attending primary care. It will provide important data on health risk profiles of young people attending general practice and on the effects of the intervention on engagement with primary care and health outcomes over 12 months. ISRCTN16059206.

  20. The prevention access and risk taking in young people (PARTY) project protocol: A cluster randomised controlled trial of health risk screening and motivational interviewing for young people presenting to general practice

    PubMed Central

    2012-01-01

    Background There are growing worldwide concerns about the ability of primary health care systems to manage the major burden of illness in young people. Over two thirds of premature adult deaths result from risks that manifest in adolescence, including injury, neuropsychiatric problems and consequences of risky behaviours. One policy response is to better reorientate primary health services towards prevention and early intervention. Currently, however, there is insufficient evidence to support this recommendation for young people. This paper describes the design and implementation of a trial testing an intervention to promote psychosocial risk screening of all young people attending general practice and to respond to identified risks using motivational interviewing. Main outcomes: clinicians’ detection of risk-taking and emotional distress, young people’s intention to change and reduction of risk taking. Secondary outcomes: pathways to care, trust in the clinician and likelihood of returning for future visits. The design of the economic and process evaluation are not detailed in this protocol. Methods PARTY is a cluster randomised trial recruiting 42 general practices in Victoria, Australia. Baseline measures include: youth friendly practice characteristics; practice staff’s self-perceived competency in young people’s care and clinicians’ detection and response to risk taking behaviours and emotional distress in 14–24 year olds, attending the practice. Practices are then stratified by a social disadvantage index and billing methods and randomised. Intervention practices receive: nine hours of training and tools; feedback of their baseline data and two practice visits over six weeks. Comparison practices receive a three hour seminar in youth friendly practice only. Six weeks post-intervention, 30 consecutive young people are interviewed post-consultation from each practice and followed-up for self-reported risk taking behaviour and emotional distress three and 12 months post consultation. Discussion The PARTY trial is the first to examine the effectiveness and efficiency of a psychosocial risk screening and counselling intervention for young people attending primary care. It will provide important data on health risk profiles of young people attending general practice and on the effects of the intervention on engagement with primary care and health outcomes over 12 months. Trial registration ISRCTN16059206 PMID:22672481

  1. Self-referenced continuous-variable quantum key distribution protocol

    DOE PAGES

    Soh, Daniel Beom Soo; Sarovar, Mohan; Brif, Constantin; ...

    2015-10-21

    We introduce a new continuous-variable quantum key distribution (CV-QKD) protocol, self-referenced CV-QKD, that eliminates the need for transmission of a high-power local oscillator between the communicating parties. In this protocol, each signal pulse is accompanied by a reference pulse (or a pair of twin reference pulses), used to align Alice’s and Bob’s measurement bases. The method of phase estimation and compensation based on the reference pulse measurement can be viewed as a quantum analog of intradyne detection used in classical coherent communication, which extracts the phase information from the modulated signal. We present a proof-of-principle, fiber-based experimental demonstration of themore » protocol and quantify the expected secret key rates by expressing them in terms of experimental parameters. Our analysis of the secret key rate fully takes into account the inherent uncertainty associated with the quantum nature of the reference pulse(s) and quantifies the limit at which the theoretical key rate approaches that of the respective conventional protocol that requires local oscillator transmission. The self-referenced protocol greatly simplifies the hardware required for CV-QKD, especially for potential integrated photonics implementations of transmitters and receivers, with minimum sacrifice of performance. Furthermore, it provides a pathway towards scalable integrated CV-QKD transceivers, a vital step towards large-scale QKD networks.« less

  2. Self-referenced continuous-variable quantum key distribution protocol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Soh, Daniel Beom Soo; Sarovar, Mohan; Brif, Constantin

    We introduce a new continuous-variable quantum key distribution (CV-QKD) protocol, self-referenced CV-QKD, that eliminates the need for transmission of a high-power local oscillator between the communicating parties. In this protocol, each signal pulse is accompanied by a reference pulse (or a pair of twin reference pulses), used to align Alice’s and Bob’s measurement bases. The method of phase estimation and compensation based on the reference pulse measurement can be viewed as a quantum analog of intradyne detection used in classical coherent communication, which extracts the phase information from the modulated signal. We present a proof-of-principle, fiber-based experimental demonstration of themore » protocol and quantify the expected secret key rates by expressing them in terms of experimental parameters. Our analysis of the secret key rate fully takes into account the inherent uncertainty associated with the quantum nature of the reference pulse(s) and quantifies the limit at which the theoretical key rate approaches that of the respective conventional protocol that requires local oscillator transmission. The self-referenced protocol greatly simplifies the hardware required for CV-QKD, especially for potential integrated photonics implementations of transmitters and receivers, with minimum sacrifice of performance. Furthermore, it provides a pathway towards scalable integrated CV-QKD transceivers, a vital step towards large-scale QKD networks.« less

  3. Self-Referenced Continuous-Variable Quantum Key Distribution Protocol

    NASA Astrophysics Data System (ADS)

    Soh, Daniel B. S.; Brif, Constantin; Coles, Patrick J.; Lütkenhaus, Norbert; Camacho, Ryan M.; Urayama, Junji; Sarovar, Mohan

    2015-10-01

    We introduce a new continuous-variable quantum key distribution (CV-QKD) protocol, self-referenced CV-QKD, that eliminates the need for transmission of a high-power local oscillator between the communicating parties. In this protocol, each signal pulse is accompanied by a reference pulse (or a pair of twin reference pulses), used to align Alice's and Bob's measurement bases. The method of phase estimation and compensation based on the reference pulse measurement can be viewed as a quantum analog of intradyne detection used in classical coherent communication, which extracts the phase information from the modulated signal. We present a proof-of-principle, fiber-based experimental demonstration of the protocol and quantify the expected secret key rates by expressing them in terms of experimental parameters. Our analysis of the secret key rate fully takes into account the inherent uncertainty associated with the quantum nature of the reference pulse(s) and quantifies the limit at which the theoretical key rate approaches that of the respective conventional protocol that requires local oscillator transmission. The self-referenced protocol greatly simplifies the hardware required for CV-QKD, especially for potential integrated photonics implementations of transmitters and receivers, with minimum sacrifice of performance. As such, it provides a pathway towards scalable integrated CV-QKD transceivers, a vital step towards large-scale QKD networks.

  4. Nearest private query based on quantum oblivious key distribution

    NASA Astrophysics Data System (ADS)

    Xu, Min; Shi, Run-hua; Luo, Zhen-yu; Peng, Zhen-wan

    2017-12-01

    Nearest private query is a special private query which involves two parties, a user and a data owner, where the user has a private input (e.g., an integer) and the data owner has a private data set, and the user wants to query which element in the owner's private data set is the nearest to his input without revealing their respective private information. In this paper, we first present a quantum protocol for nearest private query, which is based on quantum oblivious key distribution (QOKD). Compared to the classical related protocols, our protocol has the advantages of the higher security and the better feasibility, so it has a better prospect of applications.

  5. Performance measures in the earth observations commercialization applications program

    NASA Astrophysics Data System (ADS)

    Macauley, Molly K.

    1996-03-01

    Performance measures in the Earth Observations Commercialization Application Program (EOCAP) are key to its success and include net profitability; enhancements to industry productivity through generic innovations in industry practices, standards, and protocols; and documented contributions to public policy governing the newly developing remote sensing industry. Because EOCAP requires company co-funding, both parties to the agreement (the government and the corporate partner) have incentives to pursue these goals. Further strengthening progress towards these goals are requirements for business plans in the company's EOCAP proposal, detailed scrutiny given these plans during proposal selection, and regularly documented progress reports during project implementation.

  6. Sequential quantum secret sharing in a noisy environment aided with weak measurements

    NASA Astrophysics Data System (ADS)

    Ray, Maharshi; Chatterjee, Sourav; Chakrabarty, Indranil

    2016-05-01

    In this work we give a (n,n)-threshold protocol for sequential secret sharing of quantum information for the first time. By sequential secret sharing we refer to a situation where the dealer is not having all the secrets at the same time, at the beginning of the protocol; however if the dealer wishes to share secrets at subsequent phases she/he can realize it with the help of our protocol. First of all we present our protocol for three parties and later we generalize it for the situation where we have more (n> 3) parties. Interestingly, we show that our protocol of sequential secret sharing requires less amount of quantum as well as classical resource as compared to the situation wherein existing protocols are repeatedly used. Further in a much more realistic situation, we consider the sharing of qubits through two kinds of noisy channels, namely the phase damping channel (PDC) and the amplitude damping channel (ADC). When we carry out the sequential secret sharing in the presence of noise we observe that the fidelity of secret sharing at the kth iteration is independent of the effect of noise at the (k - 1)th iteration. In case of ADC we have seen that the average fidelity of secret sharing drops down to ½ which is equivalent to a random guess of the quantum secret. Interestingly, we find that by applying weak measurements one can enhance the average fidelity. This increase of the average fidelity can be achieved with certain trade off with the success probability of the weak measurements.

  7. Full-field implementation of a perfect eavesdropper on a quantum cryptography system.

    PubMed

    Gerhardt, Ilja; Liu, Qin; Lamas-Linares, Antía; Skaar, Johannes; Kurtsiefer, Christian; Makarov, Vadim

    2011-06-14

    Quantum key distribution (QKD) allows two remote parties to grow a shared secret key. Its security is founded on the principles of quantum mechanics, but in reality it significantly relies on the physical implementation. Technological imperfections of QKD systems have been previously explored, but no attack on an established QKD connection has been realized so far. Here we show the first full-field implementation of a complete attack on a running QKD connection. An installed eavesdropper obtains the entire 'secret' key, while none of the parameters monitored by the legitimate parties indicate a security breach. This confirms that non-idealities in physical implementations of QKD can be fully practically exploitable, and must be given increased scrutiny if quantum cryptography is to become highly secure.

  8. Radiative Transfer Modeling in Proto-planetary Disks

    NASA Astrophysics Data System (ADS)

    Kasper, David; Jang-Condell, Hannah; Kloster, Dylan

    2016-01-01

    Young Stellar Objects (YSOs) are rich astronomical research environments. Planets form in circumstellar disks of gas and dust around YSOs. With ever increasing capabilities of the observational instruments designed to look at these proto-planetary disks, most notably GPI, SPHERE, and ALMA, more accurate interfaces must be made to connect modeling of the disks with observation. PaRTY (Parallel Radiative Transfer in YSOs) is a code developed previously to model the observable density and temperature structure of such a disk by self-consistently calculating the structure of the disk based on radiative transfer physics. We present upgrades we are implementing to the PaRTY code to improve its accuracy and flexibility. These upgrades include: creating a two-sided disk model, implementing a spherical coordinate system, and implementing wavelength-dependent opacities. These upgrades will address problems in the PaRTY code of infinite optical thickness, calculation under/over-resolution, and wavelength-independent photon penetration depths, respectively. The upgraded code will be used to better model disk perturbations resulting from planet formation.

  9. AD HOC Networks for the Autonomous Car

    NASA Astrophysics Data System (ADS)

    Ron, Davidescu; Negrus, Eugen

    2017-10-01

    The future of the vehicle is made of cars, roads and infrastructures connected in a two way automated communication in a holistic system. It is a mandatory to use Encryption to maintain Confidentiality, Integrity and Availability in an ad hoc vehicle network. Vehicle to Vehicle communication, requires multichannel interaction between mobile, moving and changing parties to insure the full benefit from data sharing and real time decision making, a network of such users referred as mobile ad hoc network (MANET), however as ad hoc networks were not implemented in such a scale, it is not clear what is the best method and protocol to apply. Furthermore the visibility of secure preferred asymmetric encrypted ad hoc networks in a real time environment of dense moving autonomous vehicles has to be demonstrated, In order to evaluate the performance of Ad Hoc networks in changing conditions a simulation of multiple protocols was performed on large number of mobile nodes. The following common routing protocols were tested, DSDV is a proactive protocol, every mobile station maintains a routing table with all available destinations, DSR is a reactive routing protocol which allows nodes in the MANET to dynamically discover a source route across multiple network hops, AODV is a reactive routing protocol Instead of being proactive. It minimizes the number of broadcasts by creating routes based on demand, SAODV is a secure version of AODV, requires heavyweight asymmetric cryptographic, ARIANDE is a routing protocol that relies on highly efficient symmetric cryptography the concept is primarily based on DSR. A methodical evolution was performed in a various density of transportation, based on known communication bench mark parameters including, Throughput Vs. time, Routing Load per packets and bytes. Out of the none encrypted protocols, It is clear that in terms of performance of throughput and routing load DSR protocol has a clear advantage the high node number mode. The encrypted protocols show lower performance with ARIANDE being superior to SAODV and SRP. Nevertheless all protocol simulation proved it to match required real time performance.

  10. Protocol for Direct Counterfactual Quantum Communication

    NASA Astrophysics Data System (ADS)

    Salih, Hatim; Li, Zheng-Hong; Al-Amri, M.; Zubairy, M. Suhail

    2013-04-01

    It has long been assumed in physics that for information to travel between two parties in empty space, “Alice” and “Bob,” physical particles have to travel between them. Here, using the “chained” quantum Zeno effect, we show how, in the ideal asymptotic limit, information can be transferred between Alice and Bob without any physical particles traveling between them.

  11. Evaluation of the Telecommunications Protocol Processing Subsystem Using Reconfigurable Interoperable Gate Array

    NASA Technical Reports Server (NTRS)

    Pang, Jackson; Liddicoat, Albert; Ralston, Jesse; Pingree, Paula

    2006-01-01

    The current implementation of the Telecommunications Protocol Processing Subsystem Using Reconfigurable Interoperable Gate Arrays (TRIGA) is equipped with CFDP protocol and CCSDS Telemetry and Telecommand framing schemes to replace the CPU intensive software counterpart implementation for reliable deep space communication. We present the hardware/software co-design methodology used to accomplish high data rate throughput. The hardware CFDP protocol stack implementation is then compared against the two recent flight implementations. The results from our experiments show that TRIGA offers more than 3 orders of magnitude throughput improvement with less than one-tenth of the power consumption.

  12. Curated eutherian third party data gene data sets.

    PubMed

    Premzl, Marko

    2016-03-01

    The free available eutherian genomic sequence data sets advanced scientific field of genomics. Of note, future revisions of gene data sets were expected, due to incompleteness of public eutherian genomic sequence assemblies and potential genomic sequence errors. The eutherian comparative genomic analysis protocol was proposed as guidance in protection against potential genomic sequence errors in public eutherian genomic sequences. The protocol was applicable in updates of 7 major eutherian gene data sets, including 812 complete coding sequences deposited in European Nucleotide Archive as curated third party data gene data sets.

  13. Efficient Entanglement Concentration of Nonlocal Two-Photon Polarization-Time-Bin Hyperentangled States

    NASA Astrophysics Data System (ADS)

    Wang, Zi-Hang; Yu, Wen-Xuan; Wu, Xiao-Yuan; Gao, Cheng-Yan; Alzahrani, Faris; Hobiny, Aatef; Deng, Fu-Guo

    2018-03-01

    We present two different hyperentanglement concentration protocols (hyper-ECPs) for two-photon systems in nonlocal polarization-time-bin hyperentangled states with known parameters, including Bell-like and cluster-like states, resorting to the parameter splitting method. They require only one of two parties in quantum communication to operate her photon in the process of entanglement concentration, not two, and they have the maximal success probability. They work with linear optical elements and have good feasibility in experiment, especially in the case that there are a big number of quantum data exchanged as the parties can obtain the information about the parameters of the nonlocal hyperentangled states by sampling a subset of nonlocal hyperentangled two-photon systems and measuring them. As the quantum state of photons in the time-bin degree of freedom suffers from less noise in an optical-fiber channel, these hyper-ECPs may have good applications in practical long-distance quantum communication in the future.

  14. Probabilistic direct counterfactual quantum communication

    NASA Astrophysics Data System (ADS)

    Zhang, Sheng

    2017-02-01

    It is striking that the quantum Zeno effect can be used to launch a direct counterfactual communication between two spatially separated parties, Alice and Bob. So far, existing protocols of this type only provide a deterministic counterfactual communication service. However, this counterfactuality should be payed at a price. Firstly, the transmission time is much longer than a classical transmission costs. Secondly, the chained-cycle structure makes them more sensitive to channel noises. Here, we extend the idea of counterfactual communication, and present a probabilistic-counterfactual quantum communication protocol, which is proved to have advantages over the deterministic ones. Moreover, the presented protocol could evolve to a deterministic one solely by adjusting the parameters of the beam splitters. Project supported by the National Natural Science Foundation of China (Grant No. 61300203).

  15. A secure protocol for protecting the identity of providers when disclosing data for disease surveillance

    PubMed Central

    Hu, Jun; Mercer, Jay; Peyton, Liam; Kantarcioglu, Murat; Malin, Bradley; Buckeridge, David; Samet, Saeed; Earle, Craig

    2011-01-01

    Background Providers have been reluctant to disclose patient data for public-health purposes. Even if patient privacy is ensured, the desire to protect provider confidentiality has been an important driver of this reluctance. Methods Six requirements for a surveillance protocol were defined that satisfy the confidentiality needs of providers and ensure utility to public health. The authors developed a secure multi-party computation protocol using the Paillier cryptosystem to allow the disclosure of stratified case counts and denominators to meet these requirements. The authors evaluated the protocol in a simulated environment on its computation performance and ability to detect disease outbreak clusters. Results Theoretical and empirical assessments demonstrate that all requirements are met by the protocol. A system implementing the protocol scales linearly in terms of computation time as the number of providers is increased. The absolute time to perform the computations was 12.5 s for data from 3000 practices. This is acceptable performance, given that the reporting would normally be done at 24 h intervals. The accuracy of detection disease outbreak cluster was unchanged compared with a non-secure distributed surveillance protocol, with an F-score higher than 0.92 for outbreaks involving 500 or more cases. Conclusion The protocol and associated software provide a practical method for providers to disclose patient data for sentinel, syndromic or other indicator-based surveillance while protecting patient privacy and the identity of individual providers. PMID:21486880

  16. New Evaluation of the Electronically Activated Recorder (EAR): Obtrusiveness, Compliance, and Participant Self-selection Effects

    PubMed Central

    Manson, Joseph H.; Robbins, Megan L.

    2017-01-01

    The Electronically Activated Recorder (EAR) is a method for collecting periodic brief audio snippets of participants’ daily lives using a portable recording device. The EAR can potentially intrude into people’s privacy, alter their natural behavior, and introduce self-selection biases greater than in other types of social science methods. Previous research (Mehl and Holleran, 2007, hereafter M&H) has shown that participant non-compliance with, and perceived obtrusiveness of, an EAR protocol are both low. However, these questions have not been addressed in jurisdictions that require the consent of all parties to recording conversations. This EAR study required participants to wear a button bearing a microphone icon and the words “This conversation may be recorded” to comply with California’s all-party consent law. Results revealed self-reported obtrusiveness and non-compliance were actually lower in the present study than in the M&H study. Behaviorally assessed non-compliance did not differ between the two studies. Participants in the present study talked more about being in the study than participants in the M&H study, but such talk still comprised <2% of sampled conversations. Another potential problem with the EAR, participant self-selection bias, was addressed by comparing the EAR volunteers’ HEXACO personality dimensions to a non-volunteer sample drawn from the same student population. EAR volunteers were significantly and moderately higher in Conscientiousness, and lower in Emotionality, than non-volunteers. In conclusion, the EAR method can be successfully implemented in at least one all-party consent state (California). Interested researchers are encouraged to review this procedure with their own legal counsel. PMID:28503162

  17. Quantum private comparison protocol based on the entanglement swapping between χ ^+ state and W-Class state

    NASA Astrophysics Data System (ADS)

    Xu, Ling; Zhao, Zhiwen

    2017-12-01

    Quantum private comparison (QPC) protocol, including Alice, Bob and the third party Charlie, aims at comparing Alice and Bob's secret inputs correctly without leaking them. Firstly, χ ^+ state and W-Class state are used to conduct the entanglement swapping in this protocol. Either the basis {|φ ^± > ,|ψ ^± >} or the basis {|χ ^± > ,|ω ^± > } is chosen by Alice and Bob based on the predetermined value to measure the particle pairs. And three bits of secret inputs can be compared in this protocol in every comparison time, while most of previous QPC protocols can only compare one or two bits. The qubit efficiency of this protocol is 60% more than others, which are 50% at most. Secondly, if the eavesdropper intends to obtain the secret inputs, it is important and primary to get the measurement results of particle pairs. In this protocol, even if the eavesdropper gets the accurate particle pairs, he cannot get the right measurement results without the right basis. Finally, this protocol is analyzed to be able to defend the secret inputs against various kinds of attack.

  18. Proof-of-principle experimental realization of a qubit-like qudit-based quantum key distribution scheme

    NASA Astrophysics Data System (ADS)

    Wang, Shuang; Yin, Zhen-Qiang; Chau, H. F.; Chen, Wei; Wang, Chao; Guo, Guang-Can; Han, Zheng-Fu

    2018-04-01

    In comparison to qubit-based protocols, qudit-based quantum key distribution ones generally allow two cooperative parties to share unconditionally secure keys under a higher channel noise. However, it is very hard to prepare and measure the required quantum states in qudit-based protocols in general. One exception is the recently proposed highly error tolerant qudit-based protocol known as the Chau15 (Chau 2015 Phys. Rev. A 92 062324). Remarkably, the state preparation and measurement in this protocol can be done relatively easily since the required states are phase encoded almost like the diagonal basis states of a qubit. Here we report the first proof-of-principle demonstration of the Chau15 protocol. One highlight of our experiment is that its post-processing is based on practical one-way manner, while the original proposal in Chau (2015 Phys. Rev. A 92 062324) relies on complicated two-way post-processing, which is a great challenge in experiment. In addition, by manipulating time-bin qudit and measurement with a variable delay interferometer, our realization is extensible to qudit with high-dimensionality and confirms the experimental feasibility of the Chau15 protocol.

  19. Continuous-variable measurement-device-independent quantum key distribution with virtual photon subtraction

    NASA Astrophysics Data System (ADS)

    Zhao, Yijia; Zhang, Yichen; Xu, Bingjie; Yu, Song; Guo, Hong

    2018-04-01

    The method of improving the performance of continuous-variable quantum key distribution protocols by postselection has been recently proposed and verified. In continuous-variable measurement-device-independent quantum key distribution (CV-MDI QKD) protocols, the measurement results are obtained from untrusted third party Charlie. There is still not an effective method of improving CV-MDI QKD by the postselection with untrusted measurement. We propose a method to improve the performance of coherent-state CV-MDI QKD protocol by virtual photon subtraction via non-Gaussian postselection. The non-Gaussian postselection of transmitted data is equivalent to an ideal photon subtraction on the two-mode squeezed vacuum state, which is favorable to enhance the performance of CV-MDI QKD. In CV-MDI QKD protocol with non-Gaussian postselection, two users select their own data independently. We demonstrate that the optimal performance of the renovated CV-MDI QKD protocol is obtained with the transmitted data only selected by Alice. By setting appropriate parameters of the virtual photon subtraction, the secret key rate and tolerable excess noise are both improved at long transmission distance. The method provides an effective optimization scheme for the application of CV-MDI QKD protocols.

  20. How to customize a bona fide psychotherapy for generalized anxiety disorder? A two-arms, patient blinded, ABAB crossed-therapist randomized clinical implementation trial design [IMPLEMENT 2.0].

    PubMed

    Flückiger, Christoph; Wolfer, Christine; Held, Judith; Hilpert, Peter; Rubel, Julian; Allemand, Mathias; Zinbarg, Richard E; Vîslă, Andreea

    2018-04-03

    Bona fide psychotherapy approaches are effective treatments for generalized anxiety disorder (GAD) compared to no-treatment conditions. Treatment manuals and protocols allow a relatively high degree of freedom for the way therapists implement these overall treatment packages and there is a systematic lack of knowledge on how therapists should customize these treatments. The present study experimentally examines two implementation strategies of customizing a bona fide psychotherapy approach based on a 16 session time-limited cognitive-behavioral therapy (CBT) protocol and their relation to the post-session and ultimate treatment outcomes. This trial contrasts two different implementation strategies of how to customize the in-session structure of a manual-based CBT-protocol for GAD. The patients will be randomly assigned to two implementation conditions: (1) a systematic focus on subtle changes lasting from 7 to 20 min at the check-in phase of every psychotherapy session and (2) a state-of-the-art (SOTA) check-in phase lasting several minutes mainly focused on the session goals. Potential therapist effects will be examined based on an ABAB crossed-therapist design. Treatment outcomes will be assessed at the following times: post-session outcomes, treatment outcome at post assessment and 6- as well as 12-month follow-up. The proposed randomized clinical implementation trial addresses the clinically relevant question of how to customize a bona fide psychotherapy protocol experimentally contrasting two implementation strategies. Through the development and testing of the proposed implementation design, this trial has the potential to inform therapists about efficacious implementation strategies of how to customize a manual-based treatment protocol in respect to the timing of the in-session structure. This trial was registered at ClinicalTrials.gov ( NCT03079336 ) at March 14, 2017.

  1. Time and Space Efficient Algorithms for Two-Party Authenticated Data Structures

    NASA Astrophysics Data System (ADS)

    Papamanthou, Charalampos; Tamassia, Roberto

    Authentication is increasingly relevant to data management. Data is being outsourced to untrusted servers and clients want to securely update and query their data. For example, in database outsourcing, a client's database is stored and maintained by an untrusted server. Also, in simple storage systems, clients can store very large amounts of data but at the same time, they want to assure their integrity when they retrieve them. In this paper, we present a model and protocol for two-party authentication of data structures. Namely, a client outsources its data structure and verifies that the answers to the queries have not been tampered with. We provide efficient algorithms to securely outsource a skip list with logarithmic time overhead at the server and client and logarithmic communication cost, thus providing an efficient authentication primitive for outsourced data, both structured (e.g., relational databases) and semi-structured (e.g., XML documents). In our technique, the client stores only a constant amount of space, which is optimal. Our two-party authentication framework can be deployed on top of existing storage applications, thus providing an efficient authentication service. Finally, we present experimental results that demonstrate the practical efficiency and scalability of our scheme.

  2. Lemnos interoperable security project.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Halbgewachs, Ronald D.

    2010-03-01

    With the Lemnos framework, interoperability of control security equipment is straightforward. To obtain interoperability between proprietary security appliance units, one or both vendors must now write cumbersome 'translation code.' If one party changes something, the translation code 'breaks.' The Lemnos project is developing and testing a framework that uses widely available security functions and protocols like IPsec - to form a secure communications channel - and Syslog, to exchange security log messages. Using this model, security appliances from two or more different vendors can clearly and securely exchange information, helping to better protect the total system. Simplify regulatory compliance inmore » a complicated security environment by leveraging the Lemnos framework. As an electric utility, are you struggling to implement the NERC CIP standards and other regulations? Are you weighing the misery of multiple management interfaces against committing to a ubiquitous single-vendor solution? When vendors build their security appliances to interoperate using the Lemnos framework, it becomes practical to match best-of-breed offerings from an assortment of vendors to your specific control systems needs. The Lemnos project is developing and testing a framework that uses widely available open-source security functions and protocols like IPsec and Syslog to create a secure communications channel between appliances in order to exchange security data.« less

  3. Practical issues in quantum-key-distribution postprocessing

    NASA Astrophysics Data System (ADS)

    Fung, Chi-Hang Fred; Ma, Xiongfeng; Chau, H. F.

    2010-01-01

    Quantum key distribution (QKD) is a secure key generation method between two distant parties by wisely exploiting properties of quantum mechanics. In QKD, experimental measurement outcomes on quantum states are transformed by the two parties to a secret key. This transformation is composed of many logical steps (as guided by security proofs), which together will ultimately determine the length of the final secret key and its security. We detail the procedure for performing such classical postprocessing taking into account practical concerns (including the finite-size effect and authentication and encryption for classical communications). This procedure is directly applicable to realistic QKD experiments and thus serves as a recipe that specifies what postprocessing operations are needed and what the security level is for certain lengths of the keys. Our result is applicable to the BB84 protocol with a single or entangled photon source.

  4. Quantum gates by inverse engineering of a Hamiltonian

    NASA Astrophysics Data System (ADS)

    Santos, Alan C.

    2018-01-01

    Inverse engineering of a Hamiltonian (IEH) from an evolution operator is a useful technique for the protocol of quantum control with potential applications in quantum information processing. In this paper we introduce a particular protocol to perform IEH and we show how this scheme can be used to implement a set of quantum gates by using minimal quantum resources (such as entanglement, interactions between more than two qubits or auxiliary qubits). Remarkably, while previous protocols request three-qubit interactions and/or auxiliary qubits to implement such gates, our protocol requires just two-qubit interactions and no auxiliary qubits. By using this approach we can obtain a large class of Hamiltonians that allow us to implement single and two-qubit gates necessary for quantum computation. To conclude this article we analyze the performance of our scheme against systematic errors related to amplitude noise, where we show that the free parameters introduced in our scheme can be useful for enhancing the robustness of the protocol against such errors.

  5. From design to implementation--the Joint Asia Diabetes Evaluation (JADE) program: a descriptive report of an electronic web-based diabetes management program.

    PubMed

    Ko, Gary T; So, Wing-Yee; Tong, Peter C; Le Coguiec, Francois; Kerr, Debborah; Lyubomirsky, Greg; Tamesis, Beaver; Wolthers, Troels; Nan, Jennifer; Chan, Juliana

    2010-05-13

    The Joint Asia Diabetes Evaluation (JADE) Program is a web-based program incorporating a comprehensive risk engine, care protocols, and clinical decision support to improve ambulatory diabetes care. The JADE Program uses information technology to facilitate healthcare professionals to create a diabetes registry and to deliver an evidence-based care and education protocol tailored to patients' risk profiles. With written informed consent from participating patients and care providers, all data are anonymized and stored in a databank to establish an Asian Diabetes Database for research and publication purpose. The JADE electronic portal (e-portal: http://www.jade-adf.org) is implemented as a Java application using the Apache web server, the mySQL database and the Cocoon framework. The JADE e-portal comprises a risk engine which predicts 5-year probability of major clinical events based on parameters collected during an annual comprehensive assessment. Based on this risk stratification, the JADE e-portal recommends a care protocol tailored to these risk levels with decision support triggered by various risk factors. Apart from establishing a registry for quality assurance and data tracking, the JADE e-portal also displays trends of risk factor control at each visit to promote doctor-patient dialogues and to empower both parties to make informed decisions. The JADE Program is a prototype using information technology to facilitate implementation of a comprehensive care model, as recommended by the International Diabetes Federation. It also enables health care teams to record, manage, track and analyze the clinical course and outcomes of people with diabetes.

  6. How to make optimal use of maximal multipartite entanglement in clock synchronization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ren, Changliang; Hofmann, Holger F.

    2014-12-04

    We introduce a multi-party quantum clock synchronization protocol that makes optimal use of the maximal multipartite entanglement of GHZ-type states. The measurement statistics of the protocol are analyzed and the efficiency is evaluated.

  7. Effectiveness of the P.A.R.T.Y. (Prevent Alcohol and Risk-related Trauma in Youth) program in preventing traumatic injuries: a 10-year analysis.

    PubMed

    Banfield, Joanne M; Gomez, Manuel; Kiss, Alex; Redelmeier, Donald A; Brenneman, Frederick

    2011-03-01

    The P.A.R.T.Y. (Prevent Alcohol and Risk-Related Trauma in Youth) program is a 1-day injury awareness and prevention program for youth aged 15 years and older. The goal is to teach adolescents to recognize their injury risks and make informed decisions to reduce them. This study assessed the effectiveness of the P.A.R.T.Y. Program in preventing traumatic injuries during a period of 10 years (1992-2004). P.A.R.T.Y. participants (STUDY) were matched with subjects having the same age, gender, residential area, and initial year in database, who did not attend the P.A.R.T.Y. Program (CONTROL). Data from hospital discharge database, and provincial health claims, were searched to determine the incidence of traumatic injuries in both groups. Statistical comparisons were made for the two groups, gender, calendar year, and before and after the graduating driver licensing system was implemented, using the χ and conditional logistic regression analysis with a p<0.05 considered significant. Of 3,905 P.A.R.T.Y. participants, 1,281 were successfully randomly matched on the above 4 variables with 1,281 controls. The most frequent injury was injury by other or homicide 373 of 2,562 (14.8%). There were fewer traumatic injuries in the STUDY group than in the CONTROL group (43.3% vs. 47.4%; p=0.02; OR, 1.22; 95% CI, 1.03-1.45). This difference was stronger in females (44.4% vs. 49.0%; p=0.04) and before the graduating driver licensing system implementation (60.1% vs. 67.2%; p=0.04). The P.A.R.T.Y. Program effectively reduced the incidence of traumatic injuries among its participants. This effectiveness was stronger among females and before the driver licensing system was implemented. Copyright © 2011 by Lippincott Williams & Wilkins

  8. Mock climate summit: teaching and assessing learning

    NASA Astrophysics Data System (ADS)

    Schweizer, D.; Gautier, C.; Bazerman, C.

    2003-04-01

    This paper will demonstrate the effectiveness of a Mock Climate Summit as a pedagogical approach for teaching the science and policy aspects of global climate change. The Mock Climate Summit is a student-centered course simulating the Conference of the Parties (COP) where international environmental protocols are negotiated. Compared to traditional lecture-based methods common in the geoscience classroom, the Mock Climate Summit uses negotiations and arguments to teach the interactions between these two “spheres” and demonstrate the depth and breadth of these interactions. Through a detailed assessment of students’ dialogue transcribed from video and audio tapes, we found that the nature of the student dialogue matures rapidly as they are given multiple opportunities to present, negotiate and argue a specific topic. Students’ dialogue progress from hypothetical (what-if) scenarios to action-oriented scenarios and implementation plans. The progression of the students’ dialogue shows increased comfort with the communities’ discourse as they take ownership of the point-of-view associated with their assumed roles.

  9. Mock Climate Summit: Teaching and Assessing Learning

    NASA Astrophysics Data System (ADS)

    Schweizer, D.; Gautier, C.; Bazerman, C.

    2003-04-01

    This paper will demonstrate the effectiveness of a Mock Climate Summit as a pedagogical for teaching the science and policy aspects of global climate change. The Mock Climate Summit is a student-centered course simulating the Conference of the Parties (COP) where international environmental protocols are negotiated. Compared to traditional lecture-based methods common in the geoscience classroom, the Mock Climate Summit uses negotiations and arguments to teach the interactions between these two "spheres" and demonstrate the depth and breadth of these interactions. Through a detailed assessment of students' dialogue transcribed from video and audio tapes, we found that the nature of the student dialogue matures rapidly as they are given multiple opportunities to present, negotiate and argue a specific topic. Students' dialogue progress from hypothetical (what-if) scenarios to action-oriented scenarios and implementation plans. The progression of the students' dialogue shows increased comfort with the communities' discourse as they take ownership of the point-of-view associated with their assumed roles.

  10. No-cloning of quantum steering

    NASA Astrophysics Data System (ADS)

    Chiu, Ching-Yi; Lambert, Neill; Liao, Teh-Lu; Nori, Franco; Li, Che-Ming

    2016-06-01

    Einstein-Podolsky-Rosen (EPR) steering allows two parties to verify their entanglement, even if one party’s measurements are untrusted. This concept has not only provided new insights into the nature of non-local spatial correlations in quantum mechanics, but also serves as a resource for one-sided device-independent quantum information tasks. Here, we investigate how EPR steering behaves when one-half of a maximally entangled pair of qudits (multidimensional quantum systems) is cloned by a universal cloning machine. We find that EPR steering, as verified by a criterion based on the mutual information between qudits, can only be found in one of the copy subsystems but not both. We prove that this is also true for the single-system analogue of EPR steering. We find that this restriction, which we term ‘no-cloning of quantum steering’, elucidates the physical reason why steering can be used to secure sources and channels against cloning-based attacks when implementing quantum communication and quantum computation protocols.

  11. Quantum and classical noise in practical quantum-cryptography systems based on polarization-entangled photons

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Castelletto, S.; Degiovanni, I.P.; Rastello, M.L.

    2003-02-01

    Quantum-cryptography key distribution (QCKD) experiments have been recently reported using polarization-entangled photons. However, in any practical realization, quantum systems suffer from either unwanted or induced interactions with the environment and the quantum measurement system, showing up as quantum and, ultimately, statistical noise. In this paper, we investigate how an ideal polarization entanglement in spontaneous parametric down-conversion (SPDC) suffers quantum noise in its practical implementation as a secure quantum system, yielding errors in the transmitted bit sequence. Since all SPDC-based QCKD schemes rely on the measurement of coincidence to assert the bit transmission between the two parties, we bundle up themore » overall quantum and statistical noise in an exhaustive model to calculate the accidental coincidences. This model predicts the quantum-bit error rate and the sifted key and allows comparisons between different security criteria of the hitherto proposed QCKD protocols, resulting in an objective assessment of performances and advantages of different systems.« less

  12. Translating Research to Practice: Overcoming Barriers to Implementing Effective Off-Campus Party Intervention. Issues in Prevention

    ERIC Educational Resources Information Center

    Higher Education Center for Alcohol, Drug Abuse, and Violence Prevention, 2012

    2012-01-01

    This issue of "Issues in Prevention" focuses on overcoming barriers in implementing effective off-campus party intervention. This issue contains the following articles: (1) Confronting the Problems Associated With Off-Campus Parties With Evidence-Based Strategies (John D. Clapp); (2) Overview of Research on Effective Off-Campus Party…

  13. Efficient entanglement distillation without quantum memory.

    PubMed

    Abdelkhalek, Daniela; Syllwasschy, Mareike; Cerf, Nicolas J; Fiurášek, Jaromír; Schnabel, Roman

    2016-05-31

    Entanglement distribution between distant parties is an essential component to most quantum communication protocols. Unfortunately, decoherence effects such as phase noise in optical fibres are known to demolish entanglement. Iterative (multistep) entanglement distillation protocols have long been proposed to overcome decoherence, but their probabilistic nature makes them inefficient since the success probability decays exponentially with the number of steps. Quantum memories have been contemplated to make entanglement distillation practical, but suitable quantum memories are not realised to date. Here, we present the theory for an efficient iterative entanglement distillation protocol without quantum memories and provide a proof-of-principle experimental demonstration. The scheme is applied to phase-diffused two-mode-squeezed states and proven to distil entanglement for up to three iteration steps. The data are indistinguishable from those that an efficient scheme using quantum memories would produce. Since our protocol includes the final measurement it is particularly promising for enhancing continuous-variable quantum key distribution.

  14. Efficient entanglement distillation without quantum memory

    PubMed Central

    Abdelkhalek, Daniela; Syllwasschy, Mareike; Cerf, Nicolas J.; Fiurášek, Jaromír; Schnabel, Roman

    2016-01-01

    Entanglement distribution between distant parties is an essential component to most quantum communication protocols. Unfortunately, decoherence effects such as phase noise in optical fibres are known to demolish entanglement. Iterative (multistep) entanglement distillation protocols have long been proposed to overcome decoherence, but their probabilistic nature makes them inefficient since the success probability decays exponentially with the number of steps. Quantum memories have been contemplated to make entanglement distillation practical, but suitable quantum memories are not realised to date. Here, we present the theory for an efficient iterative entanglement distillation protocol without quantum memories and provide a proof-of-principle experimental demonstration. The scheme is applied to phase-diffused two-mode-squeezed states and proven to distil entanglement for up to three iteration steps. The data are indistinguishable from those that an efficient scheme using quantum memories would produce. Since our protocol includes the final measurement it is particularly promising for enhancing continuous-variable quantum key distribution. PMID:27241946

  15. Security bound of cheat sensitive quantum bit commitment.

    PubMed

    He, Guang Ping

    2015-03-23

    Cheat sensitive quantum bit commitment (CSQBC) loosens the security requirement of quantum bit commitment (QBC), so that the existing impossibility proofs of unconditionally secure QBC can be evaded. But here we analyze the common features in all existing CSQBC protocols, and show that in any CSQBC having these features, the receiver can always learn a non-trivial amount of information on the sender's committed bit before it is unveiled, while his cheating can pass the security check with a probability not less than 50%. The sender's cheating is also studied. The optimal CSQBC protocols that can minimize the sum of the cheating probabilities of both parties are found to be trivial, as they are practically useless. We also discuss the possibility of building a fair protocol in which both parties can cheat with equal probabilities.

  16. Quantum Algorithms and Protocols

    NASA Astrophysics Data System (ADS)

    Divincenzo, David

    2001-06-01

    Quantum Computing is better than classical computing, but not just because it speeds up some computations. Some of the best known quantum algorithms, like Grover's, may well have their most interesting applications in settings that involve the combination of computation and communication. Thus, Grover speeds up the appointment scheduling problem by reducing the amount of communication needed between two parties who want to find a common free slot on their calendars. I will review various other applications of this sort that are being explored. Other distributed computing protocols are required to have other attributes like obliviousness and privacy; I will discuss our recent applications involving quantum data hiding.

  17. The Effect of the Dynamic Skills Protocol RTI Model on Reading Achievement in an Elementary School and the Predictive Validity of Phonics Screening Measures Implemented in the Model

    ERIC Educational Resources Information Center

    Laben, Joyce

    2012-01-01

    With the implementation of RTI, educators are attempting to find models that are the best fit for their schools. The problem solving and standard protocol models are the two most common. This study of 65 students examines a new model, the dynamic skills protocol implemented in an elementary school starting in their fourth quarter of kindergarten…

  18. 40 CFR 82.20 - Availability of consumption allowances in addition to baseline consumption allowances for class...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... period some quantity of consumption that the nation is permitted under the Montreal Protocol. (2) Trade... Party to the Protocol as set forth in this paragraph (b). A person may only receive consumption from... maximum consumption that the nation is allowed under the Protocol minus the quantity (in kilograms) traded...

  19. 40 CFR 82.13 - Recordkeeping and reporting requirements for class I controlled substances.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... petition is contrary to other provisions in the Vienna Convention or the Montreal Protocol; (D) If the..., by the producer and or by other U.S. companies, to a Party to the Protocol that will be transformed... to the Protocol that will be used solely for quarantine and preshipment applications and therefore...

  20. 40 CFR 82.20 - Availability of consumption allowances in addition to baseline consumption allowances for class...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... period some quantity of consumption that the nation is permitted under the Montreal Protocol. (2) Trade... Party to the Protocol as set forth in this paragraph (b). A person may only receive consumption from... maximum consumption that the nation is allowed under the Protocol minus the quantity (in kilograms) traded...

  1. 40 CFR 82.20 - Availability of consumption allowances in addition to baseline consumption allowances for class...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... period some quantity of consumption that the nation is permitted under the Montreal Protocol. (2) Trade... Party to the Protocol as set forth in this paragraph (b). A person may only receive consumption from... maximum consumption that the nation is allowed under the Protocol minus the quantity (in kilograms) traded...

  2. 40 CFR 82.13 - Recordkeeping and reporting requirements for class I controlled substances.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... petition is contrary to other provisions in the Vienna Convention or the Montreal Protocol; (D) If the..., by the producer and or by other U.S. companies, to a Party to the Protocol that will be transformed... to the Protocol that will be used solely for quarantine and preshipment applications and therefore...

  3. 40 CFR 82.20 - Availability of consumption allowances in addition to baseline consumption allowances for class...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... period some quantity of consumption that the nation is permitted under the Montreal Protocol. (2) Trade... Party to the Protocol as set forth in this paragraph (b). A person may only receive consumption from... maximum consumption that the nation is allowed under the Protocol minus the quantity (in kilograms) traded...

  4. 40 CFR 82.20 - Availability of consumption allowances in addition to baseline consumption allowances for class...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... period some quantity of consumption that the nation is permitted under the Montreal Protocol. (2) Trade... Party to the Protocol as set forth in this paragraph (b). A person may only receive consumption from... maximum consumption that the nation is allowed under the Protocol minus the quantity (in kilograms) traded...

  5. W-state Analyzer and Multi-party Measurement-device-independent Quantum Key Distribution

    PubMed Central

    Zhu, Changhua; Xu, Feihu; Pei, Changxing

    2015-01-01

    W-state is an important resource for many quantum information processing tasks. In this paper, we for the first time propose a multi-party measurement-device-independent quantum key distribution (MDI-QKD) protocol based on W-state. With linear optics, we design a W-state analyzer in order to distinguish the four-qubit W-state. This analyzer constructs the measurement device for four-party MDI-QKD. Moreover, we derived a complete security proof of the four-party MDI-QKD, and performed a numerical simulation to study its performance. The results show that four-party MDI-QKD is feasible over 150 km standard telecom fiber with off-the-shelf single photon detectors. This work takes an important step towards multi-party quantum communication and a quantum network. PMID:26644289

  6. 76 FR 36919 - Proof of Concept Demonstration for Electronic Reporting of Clean Water Act Compliance Monitoring...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-23

    ... commercial products or services of any third-party software providers. Proof of Concept Demonstration for..., protocols, and specifications for the Exchange Network's data exchange services, the software provider shall... demonstration will focus the electronic transmission of NPDES DMRs from a third-party commercial software...

  7. Some methods for blindfolded record linkage.

    PubMed

    Churches, Tim; Christen, Peter

    2004-06-28

    The linkage of records which refer to the same entity in separate data collections is a common requirement in public health and biomedical research. Traditionally, record linkage techniques have required that all the identifying data in which links are sought be revealed to at least one party, often a third party. This necessarily invades personal privacy and requires complete trust in the intentions of that party and their ability to maintain security and confidentiality. Dusserre, Quantin, Bouzelat and colleagues have demonstrated that it is possible to use secure one-way hash transformations to carry out follow-up epidemiological studies without any party having to reveal identifying information about any of the subjects - a technique which we refer to as "blindfolded record linkage". A limitation of their method is that only exact comparisons of values are possible, although phonetic encoding of names and other strings can be used to allow for some types of typographical variation and data errors. A method is described which permits the calculation of a general similarity measure, the n-gram score, without having to reveal the data being compared, albeit at some cost in computation and data communication. This method can be combined with public key cryptography and automatic estimation of linkage model parameters to create an overall system for blindfolded record linkage. The system described offers good protection against misdeeds or security failures by any one party, but remains vulnerable to collusion between or simultaneous compromise of two or more parties involved in the linkage operation. In order to reduce the likelihood of this, the use of last-minute allocation of tasks to substitutable servers is proposed. Proof-of-concept computer programmes written in the Python programming language are provided to illustrate the similarity comparison protocol. Although the protocols described in this paper are not unconditionally secure, they do suggest the feasibility, with the aid of modern cryptographic techniques and high speed communication networks, of a general purpose probabilistic record linkage system which permits record linkage studies to be carried out with negligible risk of invasion of personal privacy.

  8. Some methods for blindfolded record linkage

    PubMed Central

    Churches, Tim; Christen, Peter

    2004-01-01

    Background The linkage of records which refer to the same entity in separate data collections is a common requirement in public health and biomedical research. Traditionally, record linkage techniques have required that all the identifying data in which links are sought be revealed to at least one party, often a third party. This necessarily invades personal privacy and requires complete trust in the intentions of that party and their ability to maintain security and confidentiality. Dusserre, Quantin, Bouzelat and colleagues have demonstrated that it is possible to use secure one-way hash transformations to carry out follow-up epidemiological studies without any party having to reveal identifying information about any of the subjects – a technique which we refer to as "blindfolded record linkage". A limitation of their method is that only exact comparisons of values are possible, although phonetic encoding of names and other strings can be used to allow for some types of typographical variation and data errors. Methods A method is described which permits the calculation of a general similarity measure, the n-gram score, without having to reveal the data being compared, albeit at some cost in computation and data communication. This method can be combined with public key cryptography and automatic estimation of linkage model parameters to create an overall system for blindfolded record linkage. Results The system described offers good protection against misdeeds or security failures by any one party, but remains vulnerable to collusion between or simultaneous compromise of two or more parties involved in the linkage operation. In order to reduce the likelihood of this, the use of last-minute allocation of tasks to substitutable servers is proposed. Proof-of-concept computer programmes written in the Python programming language are provided to illustrate the similarity comparison protocol. Conclusion Although the protocols described in this paper are not unconditionally secure, they do suggest the feasibility, with the aid of modern cryptographic techniques and high speed communication networks, of a general purpose probabilistic record linkage system which permits record linkage studies to be carried out with negligible risk of invasion of personal privacy. PMID:15222890

  9. Capping the cost of compliance with the Kyoto Protocol and recycling revenues into land-use projects.

    PubMed

    Schlamadinger, B; Obersteiner, M; Michaelowa, A; Grubb, M; Azar, C; Yamagata, Y; Goldberg, D; Read, P; Kirschbaum, M U; Fearnside, P M; Sugiyama, T; Rametsteiner, E; Böswald, K

    2001-07-14

    There is the concern among some countries that compliance costs with commitments under the Kyoto Protocol may be unacceptably high. There is also the concern that technical difficulties with the inclusion of land use, land-use change, and forestry activities in non-Annex I countries might lead to an effective exclusion of such activities from consideration under the Protocol. This paper is proposing a mechanism that addresses both these concerns. In essence, it is suggested that parties should be able to purchase fixed-price offset certificates if they feel they cannot achieve compliance through other means alone, such as by improved energy efficiency, increased use of renewable energy, or use of the flexible mechanisms in the Kyoto Protocol. These offset certificates would act as a price cap for the cost of compliance for any party to the Protocol. Revenues from purchase of the offset certificates would be directed to forest-based activities in non-Annex I countries such as forest protection that may carry multiple benefits including enhancing net carbon sequestration.

  10. 40 CFR 82.9 - Availability of production allowances in addition to baseline production allowances for class I...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... listed in appendix C to this subpart (Parties to the Montreal Protocol) must agree either to transfer to... permitted under the Montreal Protocol or to receive from the person for the current control period some... by the United States to the Secretariat of the Montreal Protocol for an essential use exemption may...

  11. 40 CFR 82.9 - Availability of production allowances in addition to baseline production allowances for class I...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... listed in appendix C to this subpart (Parties to the Montreal Protocol) must agree either to transfer to... permitted under the Montreal Protocol or to receive from the person for the current control period some... by the United States to the Secretariat of the Montreal Protocol for an essential use exemption may...

  12. 40 CFR 82.18 - Availability of production in addition to baseline production allowances for class II controlled...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... quantity of production that the nation is permitted under the Montreal Protocol or to receive from the... Article 5 allowances, for a specified control period through trades with another Party to the Protocol as... this subpart that is also listed in Appendix C, Annex 1 of the Protocol as having ratified the Beijing...

  13. 40 CFR 82.9 - Availability of production allowances in addition to baseline production allowances for class I...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... listed in appendix C to this subpart (Parties to the Montreal Protocol) must agree either to transfer to... permitted under the Montreal Protocol or to receive from the person for the current control period some... by the United States to the Secretariat of the Montreal Protocol for an essential use exemption may...

  14. 40 CFR 82.18 - Availability of production in addition to baseline production allowances for class II controlled...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... quantity of production that the nation is permitted under the Montreal Protocol or to receive from the... Article 5 allowances, for a specified control period through trades with another Party to the Protocol as... this subpart that is also listed in Appendix C, Annex 1 of the Protocol as having ratified the Beijing...

  15. 40 CFR 82.9 - Availability of production allowances in addition to baseline production allowances for class I...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... listed in appendix C to this subpart (Parties to the Montreal Protocol) must agree either to transfer to... permitted under the Montreal Protocol or to receive from the person for the current control period some... by the United States to the Secretariat of the Montreal Protocol for an essential use exemption may...

  16. 40 CFR 82.10 - Availability of consumption allowances in addition to baseline consumption allowances for class I...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... this subpart (Parties to the Montreal Protocol) must agree to transfer to the person for the current control period some amount of production that the nation is permitted under the Montreal Protocol. If the... Protocol for class I, Group I through Group V and Group VII controlled substances until January 1, 1996 and...

  17. 40 CFR 82.10 - Availability of consumption allowances in addition to baseline consumption allowances for class I...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... this subpart (Parties to the Montreal Protocol) must agree to transfer to the person for the current control period some amount of production that the nation is permitted under the Montreal Protocol. If the... Protocol for class I, Group I through Group V and Group VII controlled substances until January 1, 1996 and...

  18. 40 CFR 82.18 - Availability of production in addition to baseline production allowances for class II controlled...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... quantity of production that the nation is permitted under the Montreal Protocol or to receive from the... Article 5 allowances, for a specified control period through trades with another Party to the Protocol as... this subpart that is also listed in Appendix C, Annex 1 of the Protocol as having ratified the Beijing...

  19. 40 CFR 82.10 - Availability of consumption allowances in addition to baseline consumption allowances for class I...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... this subpart (Parties to the Montreal Protocol) must agree to transfer to the person for the current control period some amount of production that the nation is permitted under the Montreal Protocol. If the... Protocol for class I, Group I through Group V and Group VII controlled substances until January 1, 1996 and...

  20. 40 CFR 82.10 - Availability of consumption allowances in addition to baseline consumption allowances for class I...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... this subpart (Parties to the Montreal Protocol) must agree to transfer to the person for the current control period some amount of production that the nation is permitted under the Montreal Protocol. If the... Protocol for class I, Group I through Group V and Group VII controlled substances until January 1, 1996 and...

  1. 40 CFR 82.18 - Availability of production in addition to baseline production allowances for class II controlled...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... quantity of production that the nation is permitted under the Montreal Protocol or to receive from the... Article 5 allowances, for a specified control period through trades with another Party to the Protocol as... this subpart that is also listed in Appendix C, Annex 1 of the Protocol as having ratified the Beijing...

  2. 40 CFR 82.10 - Availability of consumption allowances in addition to baseline consumption allowances for class I...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... this subpart (Parties to the Montreal Protocol) must agree to transfer to the person for the current control period some amount of production that the nation is permitted under the Montreal Protocol. If the... Protocol for class I, Group I through Group V and Group VII controlled substances until January 1, 1996 and...

  3. Verification and validation of a reliable multicast protocol

    NASA Technical Reports Server (NTRS)

    Callahan, John R.; Montgomery, Todd L.

    1995-01-01

    This paper describes the methods used to specify and implement a complex communications protocol that provides reliable delivery of data in multicast-capable, packet-switching telecommunication networks. The protocol, called the Reliable Multicasting Protocol (RMP), was developed incrementally by two complementary teams using a combination of formal and informal techniques in an attempt to ensure the correctness of the protocol implementation. The first team, called the Design team, initially specified protocol requirements using a variant of SCR requirements tables and implemented a prototype solution. The second team, called the V&V team, developed a state model based on the requirements tables and derived test cases from these tables to exercise the implementation. In a series of iterative steps, the Design team added new functionality to the implementation while the V&V team kept the state model in fidelity with the implementation through testing. Test cases derived from state transition paths in the formal model formed the dialogue between teams during development and served as the vehicles for keeping the model and implementation in fidelity with each other. This paper describes our experiences in developing our process model, details of our approach, and some example problems found during the development of RMP.

  4. Procedures and methods of benefit assessments for medicines in Germany.

    PubMed

    Bekkering, Geertruida E; Kleijnen, Jos

    2008-11-01

    The Federal Joint Committee (FJC; Gemeinsamer Bundesausschuss, G-BA) defines the health-care elements that are to be reimbursed by sickness funds. To define a directive, the FJC can commission benefit assessments, which provide an overview of the scientific evidence regarding the efficacy and benefits of an intervention. This paper describes the operational implementation of the legal requirements with regard to the benefit assessments of medicines. Such benefit assessments are sometimes referred to as "isolated benefit assessments," to distinguish them from benefit assessments as part of a full economic evaluation.The FJC has the freedom to commission these assessments from any agency; however, to date the majority have commissioned the Institute for Quality and Efficiency in Health Care (IQWiG). Nevertheless, the content of this paper applies integrally to any institute commissioned for such assessments. In this report, 'the institute' is used when the text refers to any of these institutes.The legal framework for benefit assessments is laid out in the German Social Code Book version V ( http://www.sozialgesetzbuch.de ), Sects. 35b ( section 1), 139a ( section 4-6) and Sect. 139b ( section 3). It is specified that: The institute must guarantee high transparency. The institute must provide appropriate participation of relevant parties for the commission-related development of assessments, and opportunity for comment on all important segments of the assessment procedure. The institute has to report on the progress and results of the work at regular intervals. The institute is held to giving the commission to external experts. Based on the legal framework, the institute must guarantee a high procedural transparency. Transparency of the whole process should be achieved, which is evidenced by clear reporting of procedures and criteria in all phases undertaken in the benefit assessment. The most important means of enhancing transparency are: 1. To implement a scoping process to support the development of the research question. 2. To separate the work of the external experts performing the evidence assessment from that of the institute formulating recommendations. Therefore, the preliminary report as produced by external experts needs to be public, and published separately from any subsequent amendments or (draft-)reports made by the institute, which includes the institute's recommendations. 3. To implement open peer review by publishing both the comments of the reviewers and their names. Based on the legal framework, the institute must provide for adequate participation of relevant parties. These include organisations representing the interests of patients; experts of medical, pharmaceutical and health economic science and practice; the professional organisations of pharmacists and pharmaceutical companies; and experts on alternative therapies. Patients and health care professionals bring in new insights with respect to research priorities, treatment and outcomes.The relevant parties should be identified and contacted whenever the global scope of the assessment has been drafted. Subsequently, the relevant parties should be involved in defining the research question, developing the protocol and commenting on the preliminary report. To implement the involvement of relevant parties in defining the research question a scoping process is suggested. For the other phases, written comments followed by an oral discussion should be used. Finally, the relevant parties should have the right to appeal the final decision on judicial grounds. None of these steps mean that the institute would lose any part of its scientific independence.From the relevant sections of the legal framework with respect to the assessment methods, it can be concluded that: 1. The institute must ensure that the assessment is made in accordance with internationally recognised standards of evidence-based medicine (EBM). 2. The assessment is conducted in comparison with other medicines and treatment forms under consideration of the additional therapeutic benefit for the patients. 3. The minimum criteria for assessing patient benefit are improvements in the state of health, shortening the duration of illness, extension of the duration of life, reduction of side effects and improvements in quality of life. EBM refers to the application of the best available evidence to answer a research question, which can inform questions about the care of patients. The optimal design, even for effectiveness questions, is not always the randomised, controlled trial (RCT) but depends on the research question and the outcomes of interest. To increase transparency for each question, the levels of evidence examined should be made explicit. There is no empirical evidence to support the use of cutoff points with respect to the number of studies before making recommendations. To get the best available evidence for the research question(s), all relevant evidence should be considered for each question, and the best available evidence should be used to answer the question. Separate levels of evidence may have to be used for each outcome.There are many ways in which bias can be introduced in systematic reviews. Some types of bias can be prevented, other types can only be reported and, for some, the influence of the bias can be investigated. Reviews must show that potential sources of bias have been dealt with adequately.Methods used by other agencies that perform benefit assessments are useful to interpret the term 'international standards' to which the institute must comply. The National Institute for Health and Clinical Excellence (NICE) is a good example in this respect. NICE shows that it is possible to have transparent procedures for benefit assessments but that this requires detailed documentation. NICE has implemented an open procedure with respect to the comments of reviewers, which makes the procedure transparent. Although the Institute for Quality and Efficiency in Health Care (IQWiG) in Germany invites comments on their protocol and preliminary report by posting them on their website, and comments are made public, the individual comments are not evaluated openly, and therefore it remains uncertain whether or not they lead to changes in the reports. The participation of relevant parties in the assessment process as implemented by NICE guarantees a process that is transparent to all relevant parties.Transparency of the whole process is assured by clear reporting of procedures and criteria in all phases undertaken in the benefit assessment. In a scoping process, a draft scope is commented on first in writing and subsequently in the form of a scoping workshop. In this way, all relevant aspects can be heard and included in the final scope. The protocol is then developed, followed by evidence assessment. The methods used should be completely reported to show readers that the assessment has been performed with scientific rigour and that bias has been prevented where possible. All relevant parties should have the opportunity to comment on the draft protocol and the draft preliminary report. Each comment should be evaluated as to whether or not it will lead to changes, and both the comments and the evaluation should be made public to ensure transparency of this process. The same procedure should be used for the peer-review phase. Based on the final report of the evidence assessment, the institute forms recommendations and the FJC appraises the evidence.During the writing of the final report, a separation between the evidence assessment and the evidence-appraisal phase should be implemented. Ideally, this separation should be legally enforced to prevent any confusion about conflict of interests.Such a process guarantees a feasible combination of the legal requirements for transparency and involvement of relevant parties with international standards of EBM to ensure that the benefit assessments of medicines in Germany are performed according to the highest standards.

  5. [Procedures and methods of benefit assessments for medicines in Germany].

    PubMed

    Bekkering, G E; Kleijnen, J

    2008-12-01

    The Federal Joint Committee (FJC; Gemeinsamer Bundesausschuss, G-BA) defines the health-care elements that are to be reimbursed by sickness funds. To define a directive, the FJC can commission benefit assessments, which provide an overview of the scientific evidence regarding the efficacy and benefits of an intervention. This paper describes the operational implementation of the legal requirements with regard to the benefit assessments of medicines. Such benefit assessments are sometimes referred to as "isolated benefit assessments," to distinguish them from benefit assessments as part of a full economic evaluation. The FJC has the freedom to commission these assessments from any agency; however, to date the majority have commissioned the Institute for Quality and Efficiency in Health Care (IQWiG). Nevertheless, the content of this paper applies integrally to any institute commissioned for such assessments. In this report, "the institute"' is used when the text refers to any of these institutes. The legal framework for benefit assessments is laid out in the German Social Code Book version V (http://www. sozialgesetzbuch.de), Sects. 35b ( section sign 1), 139a ( section sign 4-6) and Sect. 139b ( section sign 3). It is specified that: The institute must guarantee high transparency. The institute must provide appropriate participation of relevant parties for the commission-related development of assessments, and opportunity for comment on all important segments of the assessment procedure. The institute has to report on the progress and results of the work at regular intervals. The institute is held to giving the commission to external experts. Based on the legal framework, the institute must guarantee a high procedural transparency. Transparency of the whole process should be achieved, which is evidenced by clear reporting of procedures and criteria in all phases undertaken in the benefit assessment. The most important means of enhancing transparency are: 1. To implement a scoping process to support the development of the research question. 2. To separate the work of the external experts performing the evidence assessment from that of the institute formulating recommendations. Therefore, the preliminary report as produced by external experts needs to be public, and published separately from any subsequent amendments or (draft-)reports made by the institute, which includes the institute's recommendations. 3. To implement open peer review by publishing both the comments of the reviewers and their names. Based on the legal framework, the institute must provide for adequate participation of relevant parties. These include organisations representing the interests of patients; experts of medical, pharmaceutical and health economic science and practice; the professional organisations of pharmacists and pharmaceutical companies; and experts on alternative therapies. Patients and health care professionals bring in new insights with respect to research priorities, treatment and outcomes. The relevant parties should be identified and contacted whenever the global scope of the assessment has been drafted. Subsequently, the relevant parties should be involved in defining the research question, developing the protocol and commenting on the preliminary report. To implement the involvement of relevant parties in defining the research question a scoping process is suggested. For the other phases, written comments followed by an oral discussion should be used. Finally, the relevant parties should have the right to appeal the final decision on judicial grounds. None of these steps mean that the institute would lose any part of its scientific independence. From the relevant sections of the legal framework with respect to the assessment methods, it can be concluded that: 1. The institute must ensure that the assessment is made in accordance with internationally recognised standards of evidence-based medicine (EBM). 2. The assessment is conducted in comparison with other medicines and treatment forms under consideration of the additional therapeutic benefit for the patients. 3. The minimum criteria for assessing patient benefit are improvements in the state of health, shortening the duration of illness, extension of the duration of life, reduction of side effects and improvements in quality of life. EBM refers to the application of the best available evidence to answer a research question, which can inform questions about the care of patients. The optimal design, even for effectiveness questions, is not always the randomised, controlled trial (RCT) but depends on the research question and the outcomes of interest. To increase transparency for each question, the levels of evidence examined should be made explicit. There is no empirical evidence to support the use of cutoff points with respect to the number of studies before making recommendations. To get the best available evidence for the research question(s), all relevant evidence should be considered for each question, and the best available evidence should be used to answer the question. Separate levels of evidence may have to be used for each outcome. There are many ways in which bias can be introduced in systematic reviews. Some types of bias can be prevented, other types can only be reported and, for some, the influence of the bias can be investigated. Reviews must show that potential sources of bias have been dealt with adequately. Methods used by other agencies that perform benefit assessments are useful to interpret the term 'international standards' to which the institute must comply. The National Institute for Health and Clinical Excellence (NICE) is a good example in this respect. NICE shows that it is possible to have transparent procedures for benefit assessments but that this requires detailed documentation. NICE has implemented an open procedure with respect to the comments of reviewers, which makes the procedure transparent. Although the Institute for Quality and Efficiency in Health Care (IQWiG) in Germany invites comments on their protocol and preliminary report by posting them on their website, and comments are made public, the individual comments are not evaluated openly, and therefore it remains uncertain whether or not they lead to changes in the reports. The participation of relevant parties in the assessment process as implemented by NICE guarantees a process that is transparent to all relevant parties. Transparency of the whole process is assured by clear reporting of procedures and criteria in all phases undertaken in the benefit assessment. In a scoping process, a draft scope is commented on first in writing and subsequently in the form of a scoping workshop. In this way, all relevant aspects can be heard and included in the final scope. The protocol is then developed, followed by evidence assessment. The methods used should be completely reported to show readers that the assessment has been performed with scientific rigour and that bias has been prevented where possible. All relevant parties should have the opportunity to comment on the draft protocol and the draft preliminary report. Each comment should be evaluated as to whether or not it will lead to changes, and both the comments and the evaluation should be made public to ensure transparency of this process. The same procedure should be used for the peer-review phase. Based on the final report of the evidence assessment, the institute forms recommendations and the FJC appraises the evidence. During the writing of the final report, a separation between the evidence assessment and the evidence appraisal phase should be implemented. Ideally, this separation should be legally enforced to prevent any confusion about conflict of interests. Such a process guarantees a feasible combination of the legal requirements for transparency and involvement of relevant parties with international standards of EBM to ensure that the benefit assessments of medicines in Germany are performed according to the highest standards.

  6. The Impact of a Management Protocol on the Outcomes of Child Abuse in Hospitalized Children in Hong Kong

    ERIC Educational Resources Information Center

    Lee, Anselm C. W.; Li, C. H.; So, K. T.

    2006-01-01

    Objective: To study the outcomes of children hospitalized for suspected child abuse before and after the implementation of a management protocol in a hospital in Hong Kong. Study period: Two 2-year periods before (1994-1995) and after (2002-2003) the implementation of the protocol in 1998. Methods: This is a retrospective hospital chart review in…

  7. Hydrofluorocarbon (HFC) Scenarios, Climate Effects and the Montreal Protocol

    NASA Astrophysics Data System (ADS)

    Velders, G. J. M.; Fahey, D. W.; Daniel, J. S.

    2016-12-01

    The Montreal Protocol has reduced the use of ozone-depleting substances by more than 95% from its peak levels in the 1980s. As a direct result the use of hydrofluorocarbons (HFCs) as substitute compounds has increased significantly. National regulations to limit HFC use have been adopted recently in the European Union, Japan and USA, and four proposals have been submitted to amend the Montreal Protocol to substantially reduce growth in HFC use. The Parties of the Montreal Protocol have discussed these proposals during their meetings in 2016. The effects of the national regulations and Montreal Protocol amendment proposals on climate forcings and surface temperatures will be presented. Global scenarios of HFC emissions reach 4.0-5.3 GtCO2-eq yr-1 in 2050, which corresponds to a projected growth from 2015 to 2050 which is 9% to 29% of that for CO2 over the same time period. In 2050, in percent of global HFC emissions, China ( 30%), India and the rest of Asia ( 25%), Middle East and northern Africa ( 10%), and USA ( 10%) are the principal source regions; and refrigeration and stationary air conditioning are the major use sectors. Calculated baseline emissions are reduced by 90% in 2050 by implementing the North America Montreal Protocol amendment proposal. This corresponds to a reduction in surface temperature attributed to HFCs from 0.1 oC to 0.04 oC in 2050 and from 0.3-0.4 oC to 0.02 oC in 2100.

  8. Beyond Gisin’s Theorem and its Applications: Violation of Local Realism by Two-Party Einstein-Podolsky-Rosen Steering

    PubMed Central

    Chen, Jing-Ling; Su, Hong-Yi; Xu, Zhen-Peng; Wu, Yu-Chun; Wu, Chunfeng; Ye, Xiang-Jun; Żukowski, Marek; Kwek, L. C.

    2015-01-01

    We demonstrate here that for a given mixed multi-qubit state if there are at least two observers for whom mutual Einstein-Podolsky-Rosen steering is possible, i.e. each observer is able to steer the other qubits into two different pure states by spontaneous collapses due to von Neumann type measurements on his/her qubit, then nonexistence of local realistic models is fully equivalent to quantum entanglement (this is not so without this condition). This result leads to an enhanced version of Gisin’s theorem (originally: all pure entangled states violate local realism). Local realism is violated by all mixed states with the above steering property. The new class of states allows one e.g. to perform three party secret sharing with just pairs of entangled qubits, instead of three qubit entanglements (which are currently available with low fidelity). This significantly increases the feasibility of having high performance versions of such protocols. Finally, we discuss some possible applications. PMID:26108704

  9. J-PAKE: Authenticated Key Exchange without PKI

    NASA Astrophysics Data System (ADS)

    Hao, Feng; Ryan, Peter

    Password Authenticated Key Exchange (PAKE) is one of the important topics in cryptography. It aims to address a practical security problem: how to establish secure communication between two parties solely based on a shared password without requiring a Public Key Infrastructure (PKI). After more than a decade of extensive research in this field, there have been several PAKE protocols available. The EKE and SPEKE schemes are perhaps the two most notable examples. Both techniques are however patented. In this paper, we review these techniques in detail and summarize various theoretical and practical weaknesses. In addition, we present a new PAKE solution called J-PAKE. Our strategy is to depend on well-established primitives such as the Zero-Knowledge Proof (ZKP). So far, almost all of the past solutions have avoided using ZKP for the concern on efficiency. We demonstrate how to effectively integrate the ZKP into the protocol design and meanwhile achieve good efficiency. Our protocol has comparable computational efficiency to the EKE and SPEKE schemes with clear advantages on security.

  10. From design to implementation - The Joint Asia Diabetes Evaluation (JADE) program: A descriptive report of an electronic web-based diabetes management program

    PubMed Central

    2010-01-01

    Background The Joint Asia Diabetes Evaluation (JADE) Program is a web-based program incorporating a comprehensive risk engine, care protocols, and clinical decision support to improve ambulatory diabetes care. Methods The JADE Program uses information technology to facilitate healthcare professionals to create a diabetes registry and to deliver an evidence-based care and education protocol tailored to patients' risk profiles. With written informed consent from participating patients and care providers, all data are anonymized and stored in a databank to establish an Asian Diabetes Database for research and publication purpose. Results The JADE electronic portal (e-portal: http://www.jade-adf.org) is implemented as a Java application using the Apache web server, the mySQL database and the Cocoon framework. The JADE e-portal comprises a risk engine which predicts 5-year probability of major clinical events based on parameters collected during an annual comprehensive assessment. Based on this risk stratification, the JADE e-portal recommends a care protocol tailored to these risk levels with decision support triggered by various risk factors. Apart from establishing a registry for quality assurance and data tracking, the JADE e-portal also displays trends of risk factor control at each visit to promote doctor-patient dialogues and to empower both parties to make informed decisions. Conclusions The JADE Program is a prototype using information technology to facilitate implementation of a comprehensive care model, as recommended by the International Diabetes Federation. It also enables health care teams to record, manage, track and analyze the clinical course and outcomes of people with diabetes. PMID:20465815

  11. Measurement-device-independent semiquantum key distribution

    NASA Astrophysics Data System (ADS)

    He, Jinjun; Li, Qin; Wu, Chunhui; Chan, Wai Hong; Zhang, Shengyu

    Semiquantum key distribution (SQKD) allows two parties to share a common string when one of them is quantum and the other has rather limited quantum capability. Almost all existing SQKD protocols have been proved to be robust in theory, namely that if an eavesdropper tries to gain information, he will inevitably induce some detectable errors. However, ideal devices do not exist in reality and their imperfection may result in side-channel attacks, which can be used by an adversary to get some information on the secret key string. In this paper, we design a measurement-device-independent SQKD protocol for the first time, which can remove the threat of all detector side-channel attacks and show that it is also robust. In addition, we discuss the possible use of the proposed protocol in real-world applications and in QKD networks.

  12. Instant Messaging by SIP

    NASA Astrophysics Data System (ADS)

    Muhi, Daniel; Dulai, Tibor; Jaskó, Szilárd

    2008-11-01

    SIP is a general-purpose application layer protocol which is able to establish sessions between two or more parties. These sessions are mainly telephone calls and multimedia conferences. However it can be used for other purposes like instant messaging and presence service. SIP has a very important role in mobile communication as more and more communicating applications are going mobile. In this paper we would like to show how SIP can be used for instant messaging purposes.

  13. Physical key-protected one-time pad

    PubMed Central

    Horstmeyer, Roarke; Judkewitz, Benjamin; Vellekoop, Ivo M.; Assawaworrarit, Sid; Yang, Changhuei

    2013-01-01

    We describe an encrypted communication principle that forms a secure link between two parties without electronically saving either of their keys. Instead, random cryptographic bits are kept safe within the unique mesoscopic randomness of two volumetric scattering materials. We demonstrate how a shared set of patterned optical probes can generate 10 gigabits of statistically verified randomness between a pair of unique 2 mm3 scattering objects. This shared randomness is used to facilitate information-theoretically secure communication following a modified one-time pad protocol. Benefits of volumetric physical storage over electronic memory include the inability to probe, duplicate or selectively reset any bits without fundamentally altering the entire key space. Our ability to securely couple the randomness contained within two unique physical objects can extend to strengthen hardware required by a variety of cryptographic protocols, which is currently a critically weak link in the security pipeline of our increasingly mobile communication culture. PMID:24345925

  14. Development of a manualized protocol of massage therapy for clinical trials in osteoarthritis.

    PubMed

    Ali, Ather; Kahn, Janet; Rosenberger, Lisa; Perlman, Adam I

    2012-10-04

    Clinical trial design of manual therapies may be especially challenging as techniques are often individualized and practitioner-dependent. This paper describes our methods in creating a standardized Swedish massage protocol tailored to subjects with osteoarthritis of the knee while respectful of the individualized nature of massage therapy, as well as implementation of this protocol in two randomized clinical trials. The manualization process involved a collaborative process between methodologic and clinical experts, with the explicit goals of creating a reproducible semi-structured protocol for massage therapy, while allowing some latitude for therapists' clinical judgment and maintaining consistency with a prior pilot study. The manualized protocol addressed identical specified body regions with distinct 30- and 60-min protocols, using standard Swedish strokes. Each protocol specifies the time allocated to each body region. The manualized 30- and 60-min protocols were implemented in a dual-site 24-week randomized dose-finding trial in patients with osteoarthritis of the knee, and is currently being implemented in a three-site 52-week efficacy trial of manualized Swedish massage therapy. In the dose-finding study, therapists adhered to the protocols and significant treatment effects were demonstrated. The massage protocol was manualized, using standard techniques, and made flexible for individual practitioner and subject needs. The protocol has been applied in two randomized clinical trials. This manualized Swedish massage protocol has real-world utility and can be readily utilized both in the research and clinical settings. Clinicaltrials.gov NCT00970008 (18 August 2009).

  15. Toward fidelity between specification and implementation

    NASA Technical Reports Server (NTRS)

    Callahan, John R.; Montgomery, Todd L.; Morrison, Jeff; Wu, Yunqing

    1994-01-01

    This paper describes the methods used to specify and implement a complex communications protocol that provides reliable delivery of data in multicast-capable, packet-switching telecommunication networks. The protocol, called the Reliable Multicasting Protocol (RMP), was developed incrementally by two complementary teams using a combination of formal and informal techniques in an attempt to ensure the correctness of the protocol implementation. The first team, called the Design team, initially specified protocol requirements using a variant of SCR requirements tables and implemented a prototype solution. The second team, called the V&V team, developed a state model based on the requirements tables and derived test cases from these tables to exercise the implementation. In a series of iterative steps, the Design team added new functionality to the implementation while the V&V team kept the state model in fidelity with the implementation through testing. Test cases derived from state transition paths in the formal model formed the dialogue between teams during development and served as the vehicles for keeping the model and implementation in fidelity with each other. This paper describes our experiences in developing our process model, details of our approach, and some example problems found during the development of RMP.

  16. Gaining hospital administrators' attention: ways to improve physician-hospital management dialogue.

    PubMed

    Cohn, Kenneth H; Gill, Sandra L; Schwartz, Richard W

    2005-02-01

    Despite marked differences in training and professional interests, physicians and hospital managers face similar problems stemming from the unprecedented rate of change in the health care delivery system: failure of reimbursement to keep pace with rising costs, new therapeutic modalities, increasing government and managed care regulations, heightened consumerism, and an aging patient population. In the face of these mounting challenges, both physicians and hospital managers could benefit significantly from a climate of collaboration and interdependence. This article presents a "case report" of a community teaching hospital in which practicing physicians and hospital administrators collaborated to develop an operating plan for the next 3 years to improve the practice environment. The physicians recommended new clinical priorities to enhance service to patients and families, to improve physician-physician communication, to develop clinical protocols, and to build coordinated diagnostic treatment centers, which the administration has implemented. Physicians and hospital managers can no longer pass on cost increases at will to patients and third-party payers. Nor can physicians and managers ignore the heightened power of patients and third-party payers. Effective dialogue and collaboration are in all parties' interests to optimize patient care and to develop innovative services. Despite the tensions created by competition and rapid change, transformation from a blaming to a learning environment may be a key strategic advantage in today's health care marketplace.

  17. Object Management Group object transaction service based on an X/Open and International Organization for Standardization open systems interconnection transaction processing kernel

    NASA Astrophysics Data System (ADS)

    Liang, J.; Sédillot, S.; Traverson, B.

    1997-09-01

    This paper addresses federation of a transactional object standard - Object Management Group (OMG) object transaction service (OTS) - with the X/Open distributed transaction processing (DTP) model and International Organization for Standardization (ISO) open systems interconnection (OSI) transaction processing (TP) communication protocol. The two-phase commit propagation rules within a distributed transaction tree are similar in the X/Open, ISO and OMG models. Building an OTS on an OSI TP protocol machine is possible because the two specifications are somewhat complementary. OTS defines a set of external interfaces without specific internal protocol machine, while OSI TP specifies an internal protocol machine without any application programming interface. Given these observations, and having already implemented an X/Open two-phase commit transaction toolkit based on an OSI TP protocol machine, we analyse the feasibility of using this implementation as a transaction service provider for OMG interfaces. Based on the favourable result of this feasibility study, we are implementing an OTS compliant system, which, by initiating the extensibility and openness strengths of OSI TP, is able to provide interoperability between X/Open DTP and OMG OTS models.

  18. Biased decoy-state measurement-device-independent quantum cryptographic conferencing with finite resources.

    PubMed

    Chen, RuiKe; Bao, WanSu; Zhou, Chun; Li, Hongwei; Wang, Yang; Bao, HaiZe

    2016-03-21

    In recent years, a large quantity of work have been done to narrow the gap between theory and practice in quantum key distribution (QKD). However, most of them are focus on two-party protocols. Very recently, Yao Fu et al proposed a measurement-device-independent quantum cryptographic conferencing (MDI-QCC) protocol and proved its security in the limit of infinitely long keys. As a step towards practical application for MDI-QCC, we design a biased decoy-state measurement-device-independent quantum cryptographic conferencing protocol and analyze the performance of the protocol in both the finite-key and infinite-key regime. From numerical simulations, we show that our decoy-state analysis is tighter than Yao Fu et al. That is, we can achieve the nonzero asymptotic secret key rate in long distance with approximate to 200km and we also demonstrate that with a finite size of data (say 1011 to 1013 signals) it is possible to perform secure MDI-QCC over reasonable distances.

  19. International Translation of Project EX: A Teen Tobacco Use Cessation Program

    PubMed Central

    Sussman, Steve

    2013-01-01

    Aims There are relatively few documented teen tobacco use cessation efforts outside the United States (U.S.). Project EX is an evidence-based program that consists of eight sessions, as a school-based clinic tobacco cessation-only version and a classroom-based prevention and cessation version. This paper provides a ‘snapshot’ of progress on international translation of ProjectEXpilot study work in eight countries that have been approached thus far. The program was implemented in Wuhan, China; Israel and partners; Bashkortostan, Russia; and Elche, Spain. Implementation is planned for Vienna, Austria; Mumbai, India; and Bangkok, Thailand. This work will lead eventually to a greater understanding regarding preference for type of programming (e.g., clinic versus classroom modality), challenges in recruitment and retention, program receptivity, and short-term (approximately 3-month post-program) quit rates. Protocol and Interim Results of International Translation of Project EX Convenience samples are being recruited based on previous contacts with each location. A protocol was sent to each location, proposing a controlled design, in which subjects enter cessation groups or become a wait-list control, with an immediate pretest, posttest, and 3-month follow-up. Language translation of program materials was completed in seven of the eight locations. Several variations in design and implementation were demanded though. For example, youth fear of reporting tobacco publicly mandated to researchers that the prevention/cessation classroom version be implemented in some locations (Israel and partners, and India). Program effects are suggested across countries. Conclusions Ongoing partnerships with parties actively involved in tobacco control facilitate pilot testing of teen tobacco use cessation programming. The Project EX curriculum appears quite translatable, though having flexibility in implementation modality eased being able to pilot test the program. Research on this cognitive-behavioral, motivation enhancement approach continues. PMID:23885135

  20. General immunity and superadditivity of two-way Gaussian quantum cryptography.

    PubMed

    Ottaviani, Carlo; Pirandola, Stefano

    2016-03-01

    We consider two-way continuous-variable quantum key distribution, studying its security against general eavesdropping strategies. Assuming the asymptotic limit of many signals exchanged, we prove that two-way Gaussian protocols are immune to coherent attacks. More precisely we show the general superadditivity of the two-way security thresholds, which are proven to be higher than the corresponding one-way counterparts in all cases. We perform the security analysis first reducing the general eavesdropping to a two-mode coherent Gaussian attack, and then showing that the superadditivity is achieved by exploiting the random on/off switching of the two-way quantum communication. This allows the parties to choose the appropriate communication instances to prepare the key, accordingly to the tomography of the quantum channel. The random opening and closing of the circuit represents, in fact, an additional degree of freedom allowing the parties to convert, a posteriori, the two-mode correlations of the eavesdropping into noise. The eavesdropper is assumed to have no access to the on/off switching and, indeed, cannot adapt her attack. We explicitly prove that this mechanism enhances the security performance, no matter if the eavesdropper performs collective or coherent attacks.

  1. General immunity and superadditivity of two-way Gaussian quantum cryptography

    PubMed Central

    Ottaviani, Carlo; Pirandola, Stefano

    2016-01-01

    We consider two-way continuous-variable quantum key distribution, studying its security against general eavesdropping strategies. Assuming the asymptotic limit of many signals exchanged, we prove that two-way Gaussian protocols are immune to coherent attacks. More precisely we show the general superadditivity of the two-way security thresholds, which are proven to be higher than the corresponding one-way counterparts in all cases. We perform the security analysis first reducing the general eavesdropping to a two-mode coherent Gaussian attack, and then showing that the superadditivity is achieved by exploiting the random on/off switching of the two-way quantum communication. This allows the parties to choose the appropriate communication instances to prepare the key, accordingly to the tomography of the quantum channel. The random opening and closing of the circuit represents, in fact, an additional degree of freedom allowing the parties to convert, a posteriori, the two-mode correlations of the eavesdropping into noise. The eavesdropper is assumed to have no access to the on/off switching and, indeed, cannot adapt her attack. We explicitly prove that this mechanism enhances the security performance, no matter if the eavesdropper performs collective or coherent attacks. PMID:26928053

  2. From imitation to implementation: How two- and three-year-old children learn to enforce social norms.

    PubMed

    Hardecker, Susanne; Tomasello, Michael

    2017-06-01

    Young children enforce social norms from early on, but little research has examined how this enforcement behaviour emerges. This study investigated whether observing an adult's norm enforcement influences children's own enforcement of that norm compared with observing an action demonstration without enforcement. Additionally, children experienced enforcement either following their own (second-party) or a third-party's transgression (N = 120). Results revealed that observing enforcement increased two- and three-year-old children's protest against the sanctioned action regardless of second- or third-party context. However, only three-year-olds generalized their enforcement to a novel action not matching the norm, whereas two-year-olds only protested against the previously sanctioned action. Importantly, without any enforcement demonstration, two-year-olds rarely protested at all while three-year-olds did so quite frequently. Thus, providing an opportunity to imitate enforcement seems to give rise to enforcement behaviour in two-year-olds while three-year-olds already understand normative implications following a variety of cues and even apply norm enforcement without any demonstration of how to do it. Statement of contribution What is already known on this subject? Children conform to social norms from early in development. Young children from 2 to 3 years of age also enforce social norms on third parties. What does this study add? Observing enforcement by an adult increases two- and three-year-olds' protest against the sanctioned action. It does not matter whether children experienced enforcement on their own or a third party's action. Three-, but not two-year-olds, generalize their enforcement to novel actions that do not match the norm. © 2016 The British Psychological Society.

  3. Rigidity of quantum steering and one-sided device-independent verifiable quantum computation

    NASA Astrophysics Data System (ADS)

    Gheorghiu, Alexandru; Wallden, Petros; Kashefi, Elham

    2017-02-01

    The relationship between correlations and entanglement has played a major role in understanding quantum theory since the work of Einstein et al (1935 Phys. Rev. 47 777-80). Tsirelson proved that Bell states, shared among two parties, when measured suitably, achieve the maximum non-local correlations allowed by quantum mechanics (Cirel’son 1980 Lett. Math. Phys. 4 93-100). Conversely, Reichardt et al showed that observing the maximal correlation value over a sequence of repeated measurements, implies that the underlying quantum state is close to a tensor product of maximally entangled states and, moreover, that it is measured according to an ideal strategy (Reichardt et al 2013 Nature 496 456-60). However, this strong rigidity result comes at a high price, requiring a large number of entangled pairs to be tested. In this paper, we present a significant improvement in terms of the overhead by instead considering quantum steering where the device of the one side is trusted. We first demonstrate a robust one-sided device-independent version of self-testing, which characterises the shared state and measurement operators of two parties up to a certain bound. We show that this bound is optimal up to constant factors and we generalise the results for the most general attacks. This leads us to a rigidity theorem for maximal steering correlations. As a key application we give a one-sided device-independent protocol for verifiable delegated quantum computation, and compare it to other existing protocols, to highlight the cost of trust assumptions. Finally, we show that under reasonable assumptions, the states shared in order to run a certain type of verification protocol must be unitarily equivalent to perfect Bell states.

  4. Secret-key expansion from covert communication

    NASA Astrophysics Data System (ADS)

    Arrazola, Juan Miguel; Amiri, Ryan

    2018-02-01

    Covert communication allows the transmission of messages in such a way that it is not possible for adversaries to detect that the communication is occurring. This provides protection in situations where knowledge that two parties are talking to each other may be incriminating to them. In this work, we study how covert communication can be used for a different purpose: secret key expansion. First, we show that any message transmitted in a secure covert protocol is also secret and therefore unknown to an adversary. We then propose a covert communication protocol where the amount of key consumed in the protocol is smaller than the transmitted key, thus leading to secure secret key expansion. We derive precise conditions for secret key expansion to occur, showing that it is possible when there are sufficiently low levels of noise for a given security level. We conclude by examining how secret key expansion from covert communication can be performed in a computational security model.

  5. Continuous variable quantum key distribution with modulated entangled states.

    PubMed

    Madsen, Lars S; Usenko, Vladyslav C; Lassen, Mikael; Filip, Radim; Andersen, Ulrik L

    2012-01-01

    Quantum key distribution enables two remote parties to grow a shared key, which they can use for unconditionally secure communication over a certain distance. The maximal distance depends on the loss and the excess noise of the connecting quantum channel. Several quantum key distribution schemes based on coherent states and continuous variable measurements are resilient to high loss in the channel, but are strongly affected by small amounts of channel excess noise. Here we propose and experimentally address a continuous variable quantum key distribution protocol that uses modulated fragile entangled states of light to greatly enhance the robustness to channel noise. We experimentally demonstrate that the resulting quantum key distribution protocol can tolerate more noise than the benchmark set by the ideal continuous variable coherent state protocol. Our scheme represents a very promising avenue for extending the distance for which secure communication is possible.

  6. 40 CFR Appendix J to Subpart A of... - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 18 2012-07-01 2012-07-01 false [Reserved] J Appendix J to Subpart A of Part 82-Parties to the Montreal Protocol Classied Under Article 5(1) That Have Banned the Import... Montreal Protocol Classied Under Article 5(1) That Have Banned the Import of Controlled Products That Rely...

  7. 40 CFR Appendix J to Subpart A of... - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false [Reserved] J Appendix J to Subpart A of Part 82-Parties to the Montreal Protocol Classied Under Article 5(1) That Have Banned the Import... Montreal Protocol Classied Under Article 5(1) That Have Banned the Import of Controlled Products That Rely...

  8. 40 CFR Appendix J to Subpart A of... - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 18 2014-07-01 2014-07-01 false [Reserved] J Appendix J to Subpart A of Part 82-Parties to the Montreal Protocol Classied Under Article 5(1) That Have Banned the Import... Montreal Protocol Classied Under Article 5(1) That Have Banned the Import of Controlled Products That Rely...

  9. 40 CFR Appendix J to Subpart A of... - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 18 2013-07-01 2013-07-01 false [Reserved] J Appendix J to Subpart A of Part 82-Parties to the Montreal Protocol Classied Under Article 5(1) That Have Banned the Import... Montreal Protocol Classied Under Article 5(1) That Have Banned the Import of Controlled Products That Rely...

  10. 40 CFR Appendix J to Subpart A of... - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 17 2011-07-01 2011-07-01 false [Reserved] J Appendix J to Subpart A of Part 82-Parties to the Montreal Protocol Classied Under Article 5(1) That Have Banned the Import... Montreal Protocol Classied Under Article 5(1) That Have Banned the Import of Controlled Products That Rely...

  11. Secure Multi-party Computation Protocol for Defense Applications in Military Operations Using Virtual Cryptography

    NASA Astrophysics Data System (ADS)

    Pathak, Rohit; Joshi, Satyadhar

    With the advent into the 20th century whole world has been facing the common dilemma of Terrorism. The suicide attacks on US twin towers 11 Sept. 2001, Train bombings in Madrid Spain 11 Mar. 2004, London bombings 7 Jul. 2005 and Mumbai attack 26 Nov. 2008 were some of the most disturbing, destructive and evil acts by terrorists in the last decade which has clearly shown their evil intent that they can go to any extent to accomplish their goals. Many terrorist organizations such as al Quaida, Harakat ul-Mujahidin, Hezbollah, Jaish-e-Mohammed, Lashkar-e-Toiba, etc. are carrying out training camps and terrorist operations which are accompanied with latest technology and high tech arsenal. To counter such terrorism our military is in need of advanced defense technology. One of the major issues of concern is secure communication. It has to be made sure that communication between different military forces is secure so that critical information is not leaked to the adversary. Military forces need secure communication to shield their confidential data from terrorist forces. Leakage of concerned data can prove hazardous, thus preservation and security is of prime importance. There may be a need to perform computations that require data from many military forces, but in some cases the associated forces would not want to reveal their data to other forces. In such situations Secure Multi-party Computations find their application. In this paper, we propose a new highly scalable Secure Multi-party Computation (SMC) protocol and algorithm for Defense applications which can be used to perform computation on encrypted data. Every party encrypts their data in accordance with a particular scheme. This encrypted data is distributed among some created virtual parties. These Virtual parties send their data to the TTP through an Anonymizer layer. TTP performs computation on encrypted data and announces the result. As the data sent was encrypted its actual value can’t be known by TTP and with the use of Anonymizers we have covered the identity of true source of data. Modifier tokens are generated along encryption of data which are distributed among virtual parties, then sent to TTP and finally used in the computation. Thus without revealing the data, right result can be computed and privacy of the parties is maintained. We have also given a probabilistic security analysis of hacking the protocol and shown how zero hacking security can be achieved.

  12. Wireless Authentication Protocol Implementation: Descriptions of a Zero-Knowledge Proof (ZKP) Protocol Implementation for Testing on Ground and Airborne Mobile Networks

    DTIC Science & Technology

    2015-01-01

    on AFRL’s small unmanned aerial vehicle (UAV) test bed . 15. SUBJECT TERMS Zero-Knowledge Proof Protocol Testing 16. SECURITY CLASSIFICATION OF...VERIFIER*** edition Version Information: Version 1.1.3 Version Details: Successful ZK authentication between two networked machines. Fixed a bug ...that causes intermittent bignum errors. Fixed a network hang bug and now allows continually authentication at the Verifier. Also now removing

  13. Tight finite-key analysis for quantum cryptography

    PubMed Central

    Tomamichel, Marco; Lim, Charles Ci Wen; Gisin, Nicolas; Renner, Renato

    2012-01-01

    Despite enormous theoretical and experimental progress in quantum cryptography, the security of most current implementations of quantum key distribution is still not rigorously established. One significant problem is that the security of the final key strongly depends on the number, M, of signals exchanged between the legitimate parties. Yet, existing security proofs are often only valid asymptotically, for unrealistically large values of M. Another challenge is that most security proofs are very sensitive to small differences between the physical devices used by the protocol and the theoretical model used to describe them. Here we show that these gaps between theory and experiment can be simultaneously overcome by using a recently developed proof technique based on the uncertainty relation for smooth entropies. PMID:22252558

  14. Tight finite-key analysis for quantum cryptography.

    PubMed

    Tomamichel, Marco; Lim, Charles Ci Wen; Gisin, Nicolas; Renner, Renato

    2012-01-17

    Despite enormous theoretical and experimental progress in quantum cryptography, the security of most current implementations of quantum key distribution is still not rigorously established. One significant problem is that the security of the final key strongly depends on the number, M, of signals exchanged between the legitimate parties. Yet, existing security proofs are often only valid asymptotically, for unrealistically large values of M. Another challenge is that most security proofs are very sensitive to small differences between the physical devices used by the protocol and the theoretical model used to describe them. Here we show that these gaps between theory and experiment can be simultaneously overcome by using a recently developed proof technique based on the uncertainty relation for smooth entropies.

  15. Linear-Optics-Based Entanglement Concentration of Four-Photon χ-type States for Quantum Communication Network

    NASA Astrophysics Data System (ADS)

    Li, Tao; Deng, Fu-Guo

    2014-09-01

    We present an efficient entanglement concentration protocol (ECP) for partially entangled four-photon χ-type states in the first time with only linear optical elements and single-photon detectors. Without any ancillary particles, the parties in quantum communication network can obtain a subset of four-photon systems in the standard | χ 00> state from a set of four-photon systems in a partially entangled χ-type state with the parameter-splitting method developed by Ren et al. (Phys. Rev. A 88:012302, 2013). The present ECP has the optimal success probability which is determined by the component with the minimal probability amplitude in the initial state. Moreover, it is easy to implement this ECP in experiment.

  16. Multipartite Gaussian steering: Monogamy constraints and quantum cryptography applications

    NASA Astrophysics Data System (ADS)

    Xiang, Yu; Kogias, Ioannis; Adesso, Gerardo; He, Qiongyi

    2017-01-01

    We derive laws for the distribution of quantum steering among different parties in multipartite Gaussian states under Gaussian measurements. We prove that a monogamy relation akin to the generalized Coffman-Kundu-Wootters inequality holds quantitatively for a recently introduced measure of Gaussian steering. We then define the residual Gaussian steering, stemming from the monogamy inequality, as an indicator of collective steering-type correlations. For pure three-mode Gaussian states, the residual acts as a quantifier of genuine multipartite steering, and is interpreted operationally in terms of the guaranteed key rate in the task of secure quantum secret sharing. Optimal resource states for the latter protocol are identified, and their possible experimental implementation discussed. Our results pin down the role of multipartite steering for quantum communication.

  17. Towards durable multistakeholder-generated solutions: The pilot application of a problem-oriented policy learning protocol to legality verification and community rights in Peru

    Treesearch

    D. Humphreys; B. Cashore; I.J. Visseren-Hamakers; W. De Jong; K. McGinley; A. Denvir; P. Caro Torres; S. Lupberger

    2017-01-01

    This paper reports and reflects on the pilot application of an 11-step policy learning protocol that was developed by Cashore and Lupberger (2015) based on several years of Cashore's multi-author collaborations. The protocol was applied for the first time in Peru in 2015 and 2016 by the IUFRO Working Party on Forest Policy Learning Architectures (hereinafter...

  18. Efficient Fair Exchange from Identity-Based Signature

    NASA Astrophysics Data System (ADS)

    Yum, Dae Hyun; Lee, Pil Joong

    A fair exchange scheme is a protocol by which two parties Alice and Bob exchange items or services without allowing either party to gain advantages by quitting prematurely or otherwise misbehaving. To this end, modern cryptographic solutions use a semi-trusted arbitrator who involves only in cases where one party attempts to cheat or simply crashes. We call such a fair exchange scheme optimistic. When no registration is required between the signer and the arbitrator, we say that the fair exchange scheme is setup free. To date, the setup-free optimist fair exchange scheme under the standard RSA assumption was only possible from the generic construction of [12], which uses ring signatures. In this paper, we introduce a new setup-free optimistic fair exchange scheme under the standard RSA assumption. Our scheme uses the GQ identity-based signature and is more efficient than [12]. The construction can also be generalized by using various identity-based signature schemes. Our main technique is to allow each user to choose his (or her) own “random” public key in the identitybased signature scheme.

  19. Developing a Standard Method for Link-Layer Security of CCSDS Space Communications

    NASA Technical Reports Server (NTRS)

    Biggerstaff, Craig

    2009-01-01

    Communications security for space systems has been a specialized field generally far removed from considerations of mission interoperability and cross-support in fact, these considerations often have been viewed as intrinsically opposed to security objectives. The space communications protocols defined by the Consultative Committee for Space Data Systems (CCSDS) have a twenty-five year history of successful use in over 400 missions. While the CCSDS Telemetry, Telecommand, and Advancing Orbiting Systems protocols for use at OSI Layer 2 are operationally mature, there has been no direct support within these protocols for communications security techniques. Link-layer communications security has been successfully implemented in the past using mission-unique methods, but never before with an objective of facilitating cross-support and interoperability. This paper discusses the design of a standard method for cryptographic authentication, encryption, and replay protection at the data link layer that can be integrated into existing CCSDS protocols without disruption to legacy communications services. Integrating cryptographic operations into existing data structures and processing sequences requires a careful assessment of the potential impediments within spacecraft, ground stations, and operations centers. The objective of this work is to provide a sound method for cryptographic encapsulation of frame data that also facilitates Layer 2 virtual channel switching, such that a mission may procure data transport services as needed without involving third parties in the cryptographic processing, or split independent data streams for separate cryptographic processing.

  20. IONAC-Lite

    NASA Technical Reports Server (NTRS)

    Torgerson, Jordan L.; Clare, Loren P.; Pang, Jackson

    2011-01-01

    The Interplanetary Overlay Net - working Protocol Accelerator (IONAC) described previously in The Inter - planetary Overlay Networking Protocol Accelerator (NPO-45584), NASA Tech Briefs, Vol. 32, No. 10, (October 2008) p. 106 (http://www.techbriefs.com/component/ content/article/3317) provides functions that implement the Delay Tolerant Networking (DTN) bundle protocol. New missions that require high-speed downlink-only use of DTN can now be accommodated by the unidirectional IONAC-Lite to support high data rate downlink mission applications. Due to constrained energy resources, a conventional software implementation of the DTN protocol can provide only limited throughput for any given reasonable energy consumption rate. The IONAC-Lite DTN Protocol Accelerator is able to reduce this energy consumption by an order of magnitude and increase the throughput capability by two orders of magnitude. In addition, a conventional DTN implementation requires a bundle database with a considerable storage requirement. In very high downlink datarate missions such as near-Earth radar science missions, the storage space utilization needs to be maximized for science data and minimized for communications protocol-related storage needs. The IONAC-Lite DTN Protocol Accelerator is implemented in a reconfigurable hardware device to accomplish exactly what s needed for high-throughput DTN downlink-only scenarios. The following are salient features of the IONAC-Lite implementation: An implementation of the Bundle Protocol for an environment that requires a very high rate bundle egress data rate. The C&DH (command and data handling) subsystem is also expected to be very constrained so the interaction with the C&DH processor and the temporary storage are minimized. Fully pipelined design so that bundle processing database is not required. Implements a lookup table-based approach to eliminate multi-pass processing requirement imposed by the Bundle Protocol header s length field structure and the SDNV (self-delimiting numeric value) data field formatting. 8-bit parallel datapath to support high data-rate missions. Reduced resource utilization implementation for missions that do not require custody transfer features. There was no known implementation of the DTN protocol in a field programmable gate array (FPGA) device prior to the current implementation. The combination of energy and performance optimization that embodies this design makes the work novel.

  1. Eavesdropping on counterfactual quantum key distribution with finite resources

    NASA Astrophysics Data System (ADS)

    Liu, Xingtong; Zhang, Bo; Wang, Jian; Tang, Chaojing; Zhao, Jingjing; Zhang, Sheng

    2014-08-01

    A striking scheme called "counterfactual quantum cryptography" gives a conceptually new approach to accomplish the task of key distribution. It allows two legitimate parties to share a secret even though a particle carrying secret information is not, in fact, transmitted through the quantum channel. Since an eavesdropper cannot directly access the entire quantum system of each signal particle, the protocol seems to provide practical security advantages. However, here we propose an eavesdropping method which works on the scheme in a finite key scenario. We show that, for practical systems only generating a finite number of keys, the eavesdropping can obtain all of the secret information without being detected. We also present a improved protocol as a countermeasure against this attack.

  2. Distributed Noise Generation for Density Estimation Based Clustering without Trusted Third Party

    NASA Astrophysics Data System (ADS)

    Su, Chunhua; Bao, Feng; Zhou, Jianying; Takagi, Tsuyoshi; Sakurai, Kouichi

    The rapid growth of the Internet provides people with tremendous opportunities for data collection, knowledge discovery and cooperative computation. However, it also brings the problem of sensitive information leakage. Both individuals and enterprises may suffer from the massive data collection and the information retrieval by distrusted parties. In this paper, we propose a privacy-preserving protocol for the distributed kernel density estimation-based clustering. Our scheme applies random data perturbation (RDP) technique and the verifiable secret sharing to solve the security problem of distributed kernel density estimation in [4] which assumed a mediate party to help in the computation.

  3. Multi-party Quantum Key Agreement without Entanglement

    NASA Astrophysics Data System (ADS)

    Cai, Bin-Bin; Guo, Gong-De; Lin, Song

    2017-04-01

    A new efficient quantum key agreement protocol without entanglement is proposed. In this protocol, each user encodes his secret key into the traveling particles by performing one of four rotation operations that one cannot perfectly distinguish. In the end, all users can simultaneously obtain the final shared key. The security of the presented protocol against some common attacks is discussed. It is shown that this protocol can effectively protect the privacy of each user and satisfy the requirement of fairness in theory. Moreover, the quantum carriers and the encoding operations used in the protocol can be achieved in realistic physical devices. Therefore, the presented protocol is feasible with current technology.

  4. Bridging the Gap Between Validation and Implementation of Non-Animal Veterinary Vaccine Potency Testing Methods.

    PubMed

    Dozier, Samantha; Brown, Jeffrey; Currie, Alistair

    2011-11-29

    In recent years, technologically advanced high-throughput techniques have been developed that replace, reduce or refine animal use in vaccine quality control tests. Following validation, these tests are slowly being accepted for use by international regulatory authorities. Because regulatory acceptance itself has not guaranteed that approved humane methods are adopted by manufacturers, various organizations have sought to foster the preferential use of validated non-animal methods by interfacing with industry and regulatory authorities. After noticing this gap between regulation and uptake by industry, we began developing a paradigm that seeks to narrow the gap and quicken implementation of new replacement, refinement or reduction guidance. A systematic analysis of our experience in promoting the transparent implementation of validated non-animal vaccine potency assays has led to the refinement of our paradigmatic process, presented here, by which interested parties can assess the local regulatory acceptance of methods that reduce animal use and integrate them into quality control testing protocols, or ensure the elimination of peripheral barriers to their use, particularly for potency and other tests carried out on production batches.

  5. An Approach to Verification and Validation of a Reliable Multicasting Protocol

    NASA Technical Reports Server (NTRS)

    Callahan, John R.; Montgomery, Todd L.

    1994-01-01

    This paper describes the process of implementing a complex communications protocol that provides reliable delivery of data in multicast-capable, packet-switching telecommunication networks. The protocol, called the Reliable Multicasting Protocol (RMP), was developed incrementally using a combination of formal and informal techniques in an attempt to ensure the correctness of its implementation. Our development process involved three concurrent activities: (1) the initial construction and incremental enhancement of a formal state model of the protocol machine; (2) the initial coding and incremental enhancement of the implementation; and (3) model-based testing of iterative implementations of the protocol. These activities were carried out by two separate teams: a design team and a V&V team. The design team built the first version of RMP with limited functionality to handle only nominal requirements of data delivery. In a series of iterative steps, the design team added new functionality to the implementation while the V&V team kept the state model in fidelity with the implementation. This was done by generating test cases based on suspected errant or offnominal behaviors predicted by the current model. If the execution of a test was different between the model and implementation, then the differences helped identify inconsistencies between the model and implementation. The dialogue between both teams drove the co-evolution of the model and implementation. Testing served as the vehicle for keeping the model and implementation in fidelity with each other. This paper describes (1) our experiences in developing our process model; and (2) three example problems found during the development of RMP.

  6. An approach to verification and validation of a reliable multicasting protocol

    NASA Technical Reports Server (NTRS)

    Callahan, John R.; Montgomery, Todd L.

    1995-01-01

    This paper describes the process of implementing a complex communications protocol that provides reliable delivery of data in multicast-capable, packet-switching telecommunication networks. The protocol, called the Reliable Multicasting Protocol (RMP), was developed incrementally using a combination of formal and informal techniques in an attempt to ensure the correctness of its implementation. Our development process involved three concurrent activities: (1) the initial construction and incremental enhancement of a formal state model of the protocol machine; (2) the initial coding and incremental enhancement of the implementation; and (3) model-based testing of iterative implementations of the protocol. These activities were carried out by two separate teams: a design team and a V&V team. The design team built the first version of RMP with limited functionality to handle only nominal requirements of data delivery. In a series of iterative steps, the design team added new functionality to the implementation while the V&V team kept the state model in fidelity with the implementation. This was done by generating test cases based on suspected errant or off-nominal behaviors predicted by the current model. If the execution of a test was different between the model and implementation, then the differences helped identify inconsistencies between the model and implementation. The dialogue between both teams drove the co-evolution of the model and implementation. Testing served as the vehicle for keeping the model and implementation in fidelity with each other. This paper describes (1) our experiences in developing our process model; and (2) three example problems found during the development of RMP.

  7. Improvement of "Novel Multiparty Quantum Key Agreement Protocol with GHZ States"

    NASA Astrophysics Data System (ADS)

    Gu, Jun; Hwang, Tzonelih

    2017-10-01

    Quantum key agreement (QKA) protocol is a method for negotiating a fair and secure key among mutually untrusted participants. Recently, Xu et al. (Quantum Inf. Process. 13:2587-2594, 2014) proposed a multi-party QKA protocol based on Greenberger-Horne-Zeilinger (GHZ) states. However, this study points out that Xu et al.'s protocol cannot provide the fairness property. That is, the last involved participant in the protocol can manipulate the final shared secret key without being detected by the other participants. Moreover, according to Yu et al.'s research (2015), Xu et al.'s protocol cannot avoid the public discussion attack too. To avoid these weaknesses, an improved QKA protocol is proposed.

  8. Twenty Seven Years of Quantum Cryptography!

    NASA Astrophysics Data System (ADS)

    Hughes, Richard

    2011-03-01

    One of the fundamental goals of cryptographic research is to minimize the assumptions underlying the protocols that enable secure communications between pairs or groups of users. In 1984, building on earlier research by Stephen Wiesner, Charles Bennett and Gilles Brassard showed how quantum physics could be harnessed to provide information-theoretic security for protocols such as the distribution of cryptographic keys, which enables two parties to secure their conventional communications. Bennett and Brassard and colleagues performed a proof-of-principle quantum key distribution (QKD) experiment with single-photon quantum state transmission over a 32-cm air path in 1991. This seminal experiment led other researchers to explore QKD in optical fibers and over line-of-sight outdoor atmospheric paths (``free-space''), resulting in dramatic increases in range, bit rate and security. These advances have been enabled by improvements in sources and single-photon detectors. Also in 1991 Artur Ekert showed how the security of QKD could be related to quantum entanglement. This insight led to a deeper understanding and proof of QKD security with practical sources and detectors in the presence of transmission loss and channel noise. Today, QKD has been implemented over ranges much greater than 100km in both fiber and free-space, multi-node network testbeds have been demonstrated, and satellite-based QKD is under study in several countries. ``Quantum hacking'' researchers have shown the importance of extending security considerations to the classical devices that produce and detect the photon quantum states. New quantum cryptographic protocols such as secure identification have been proposed, and others such as quantum secret splitting have been demonstrated. It is now possible to envision quantum cryptography providing a more secure alternative to present-day cryptographic methods for many secure communications functions. My talk will survey these remarkable developments.

  9. The Soviet Concept of the ’Correlation of Forces’

    DTIC Science & Technology

    1976-05-01

    activity rests on a strong foundation of objective assessments and accurate information " and that "all party docu- ments devoted to domestic problems... tekst protokolov (Thjrd Regular Congress of the Russian Social-Demoeratic Worker s Party, 1905. roll Text of the Protocols) (Moscow: State...Literature. 1949), p. 248. U pointed out at the founding conference oi the Communist Information Bureau (Comlnform) In September 1947, the

  10. Multiparty quantum key agreement protocol based on locally indistinguishable orthogonal product states

    NASA Astrophysics Data System (ADS)

    Jiang, Dong-Huan; Xu, Guang-Bao

    2018-07-01

    Based on locally indistinguishable orthogonal product states, we propose a novel multiparty quantum key agreement (QKA) protocol. In this protocol, the private key information of each party is encoded as some orthogonal product states that cannot be perfectly distinguished by local operations and classical communications. To ensure the security of the protocol with small amount of decoy particles, the different particles of each product state are transmitted separately. This protocol not only can make each participant fairly negotiate a shared key, but also can avoid information leakage in the maximum extent. We give a detailed security proof of this protocol. From comparison result with the existing QKA protocols, we can know that the new protocol is more efficient.

  11. An electronic specimen collection protocol schema (eSCPS). Document architecture for specimen management and the exchange of specimen collection protocols between biobanking information systems.

    PubMed

    Eminaga, O; Semjonow, A; Oezguer, E; Herden, J; Akbarov, I; Tok, A; Engelmann, U; Wille, S

    2014-01-01

    The integrity of collection protocols in biobanking is essential for a high-quality sample preparation process. However, there is not currently a well-defined universal method for integrating collection protocols in the biobanking information system (BIMS). Therefore, an electronic schema of the collection protocol that is based on Extensible Markup Language (XML) is required to maintain the integrity and enable the exchange of collection protocols. The development and implementation of an electronic specimen collection protocol schema (eSCPS) was performed at two institutions (Muenster and Cologne) in three stages. First, we analyzed the infrastructure that was already established at both the biorepository and the hospital information systems of these institutions and determined the requirements for the sufficient preparation of specimens and documentation. Second, we designed an eSCPS according to these requirements. Finally, a prospective study was conducted to implement and evaluate the novel schema in the current BIMS. We designed an eSCPS that provides all of the relevant information about collection protocols. Ten electronic collection protocols were generated using the supplementary Protocol Editor tool, and these protocols were successfully implemented in the existing BIMS. Moreover, an electronic list of collection protocols for the current studies being performed at each institution was included, new collection protocols were added, and the existing protocols were redesigned to be modifiable. The documentation time was significantly reduced after implementing the eSCPS (5 ± 2 min vs. 7 ± 3 min; p = 0.0002). The eSCPS improves the integrity and facilitates the exchange of specimen collection protocols in the existing open-source BIMS.

  12. Making the most of cloud storage - a toolkit for exploitation by WLCG experiments

    NASA Astrophysics Data System (ADS)

    Alvarez Ayllon, Alejandro; Arsuaga Rios, Maria; Bitzes, Georgios; Furano, Fabrizio; Keeble, Oliver; Manzi, Andrea

    2017-10-01

    Understanding how cloud storage can be effectively used, either standalone or in support of its associated compute, is now an important consideration for WLCG. We report on a suite of extensions to familiar tools targeted at enabling the integration of cloud object stores into traditional grid infrastructures and workflows. Notable updates include support for a number of object store flavours in FTS3, Davix and gfal2, including mitigations for lack of vector reads; the extension of Dynafed to operate as a bridge between grid and cloud domains; protocol translation in FTS3; the implementation of extensions to DPM (also implemented by the dCache project) to allow 3rd party transfers over HTTP. The result is a toolkit which facilitates data movement and access between grid and cloud infrastructures, broadening the range of workflows suitable for cloud. We report on deployment scenarios and prototype experience, explaining how, for example, an Amazon S3 or Azure allocation can be exploited by grid workflows.

  13. On the security of semi-device-independent QKD protocols

    NASA Astrophysics Data System (ADS)

    Chaturvedi, Anubhav; Ray, Maharshi; Veynar, Ryszard; Pawłowski, Marcin

    2018-06-01

    While fully device-independent security in (BB84-like) prepare-and-measure quantum key distribution (QKD) is impossible, it can be guaranteed against individual attacks in a semi-device-independent (SDI) scenario, wherein no assumptions are made on the characteristics of the hardware used except for an upper bound on the dimension of the communicated system. Studying security under such minimal assumptions is especially relevant in the context of the recent quantum hacking attacks wherein the eavesdroppers can not only construct the devices used by the communicating parties but are also able to remotely alter their behavior. In this work, we study the security of a SDIQKD protocol based on the prepare-and-measure quantum implementation of a well-known cryptographic primitive, the random access code (RAC). We consider imperfect detectors and establish the critical values of the security parameters (the observed success probability of the RAC and the detection efficiency) required for guaranteeing security against eavesdroppers with and without quantum memory. Furthermore, we suggest a minimal characterization of the preparation device in order to lower the requirements for establishing a secure key.

  14. The SED in the 1980’s -- New Program and Statutes for the Party

    DTIC Science & Technology

    1977-08-17

    cit., p 294. 85. Protocol, Vol 1, p 40. 86. " Scientific Communism," loc. cit., p 295. 87. Zatsepilin, V.G., "Sorevnovaniye dvukh mirovykh sistem ...Covered 14. 15. Supplementary Notes 16. Abstracts The report contains an analysis by the West German Federal Institute for Eastern Scientific ...for Eastern Scientific and International Studies] CONTENTS PAGE Summary -*- I. Historical Background 5 II. Discussion of Party Documents 6 1

  15. Efficiency and security problems of anonymous key agreement protocol based on chaotic maps

    NASA Astrophysics Data System (ADS)

    Yoon, Eun-Jun

    2012-07-01

    In 2011, Niu-Wang proposed an anonymous key agreement protocol based on chaotic maps in [Niu Y, Wang X. An anonymous key agreement protocol based on chaotic maps. Commun Nonlinear Sci Simulat 2011;16(4):1986-92]. Niu-Wang's protocol not only achieves session key agreement between a server and a user, but also allows the user to anonymously interact with the server. Nevertheless, this paper points out that Niu-Wang's protocol has the following efficiency and security problems: (1) The protocol has computational efficiency problem when a trusted third party decrypts the user sending message. (2) The protocol is vulnerable to Denial of Service (DoS) attack based on illegal message modification by an attacker.

  16. Application Level Protocol Development for Library and Information Science Applications. Volume 1: Service Definition. Volume 2: Protocol Specification. Report No. TG.1.5; TG.50.

    ERIC Educational Resources Information Center

    Aagaard, James S.; And Others

    This two-volume document specifies a protocol that was developed using the Reference Model for Open Systems Interconnection (OSI), which provides a framework for communications within a heterogeneous network environment. The protocol implements the features necessary for bibliographic searching, record maintenance, and mail transfer between…

  17. Dynamic Communication Resource Negotiations

    NASA Technical Reports Server (NTRS)

    Chow, Edward; Vatan, Farrokh; Paloulian, George; Frisbie, Steve; Srostlik, Zuzana; Kalomiris, Vasilios; Apgar, Daniel

    2012-01-01

    Today's advanced network management systems can automate many aspects of the tactical networking operations within a military domain. However, automation of joint and coalition tactical networking across multiple domains remains challenging. Due to potentially conflicting goals and priorities, human agreement is often required before implementation into the network operations. This is further complicated by incompatible network management systems and security policies, rendering it difficult to implement automatic network management, thus requiring manual human intervention to the communication protocols used at various network routers and endpoints. This process of manual human intervention is tedious, error-prone, and slow. In order to facilitate a better solution, we are pursuing a technology which makes network management automated, reliable, and fast. Automating the negotiation of the common network communication parameters between different parties is the subject of this paper. We present the technology that enables inter-force dynamic communication resource negotiations to enable ad-hoc inter-operation in the field between force domains, without pre-planning. It also will enable a dynamic response to changing conditions within the area of operations. Our solution enables the rapid blending of intra-domain policies so that the forces involved are able to inter-operate effectively without overwhelming each other's networks with in-appropriate or un-warranted traffic. It will evaluate the policy rules and configuration data for each of the domains, then generate a compatible inter-domain policy and configuration that will update the gateway systems between the two domains.

  18. Three-party authenticated key agreements for optimal communication

    PubMed Central

    Lee, Tian-Fu; Hwang, Tzonelih

    2017-01-01

    Authenticated key agreements enable users to determine session keys, and to securely communicate with others over an insecure channel via the session keys. This study investigates the lower bounds on communications for three-party authenticated key agreements and considers whether or not the sub-keys for generating a session key can be revealed in the channel. Since two clients do not share any common secret key, they require the help of the server to authenticate their identities and exchange confidential and authenticated information over insecure networks. However, if the session key security is based on asymmetric cryptosystems, then revealing the sub-keys cannot compromise the session key. The clients can directly exchange the sub-keys and reduce the transmissions. In addition, authenticated key agreements were developed by using the derived results of the lower bounds on communications. Compared with related approaches, the proposed protocols had fewer transmissions and realized the lower bounds on communications. PMID:28355253

  19. Device-independent secret-key-rate analysis for quantum repeaters

    NASA Astrophysics Data System (ADS)

    Holz, Timo; Kampermann, Hermann; Bruß, Dagmar

    2018-01-01

    The device-independent approach to quantum key distribution (QKD) aims to establish a secret key between two or more parties with untrusted devices, potentially under full control of a quantum adversary. The performance of a QKD protocol can be quantified by the secret key rate, which can be lower bounded via the violation of an appropriate Bell inequality in a setup with untrusted devices. We study secret key rates in the device-independent scenario for different quantum repeater setups and compare them to their device-dependent analogon. The quantum repeater setups under consideration are the original protocol by Briegel et al. [Phys. Rev. Lett. 81, 5932 (1998), 10.1103/PhysRevLett.81.5932] and the hybrid quantum repeater protocol by van Loock et al. [Phys. Rev. Lett. 96, 240501 (2006), 10.1103/PhysRevLett.96.240501]. For a given repeater scheme and a given QKD protocol, the secret key rate depends on a variety of parameters, such as the gate quality or the detector efficiency. We systematically analyze the impact of these parameters and suggest optimized strategies.

  20. An eCK-Secure Authenticated Key Exchange Protocol without Random Oracles

    NASA Astrophysics Data System (ADS)

    Moriyama, Daisuke; Okamoto, Tatsuaki

    This paper presents a (PKI-based) two-pass authenticated key exchange (AKE) protocol that is secure in the extended Canetti-Krawczyk (eCK) security model. The security of the proposed protocol is proven without random oracles (under three assumptions), and relies on no implementation techniques such as a trick by LaMacchia, Lauter and Mityagin (so-called the NAXOS trick). Since an AKE protocol that is eCK-secure under a NAXOS-like implementation trick will be no more eCK-secure if some realistic information leakage occurs through side-channel attacks, it has been an important open problem how to realize an eCK-secure AKE protocol without using the NAXOS tricks (and without random oracles).

  1. Optimal continuous variable quantum teleportation protocol for realistic settings

    NASA Astrophysics Data System (ADS)

    Luiz, F. S.; Rigolin, Gustavo

    2015-03-01

    We show the optimal setup that allows Alice to teleport coherent states | α > to Bob giving the greatest fidelity (efficiency) when one takes into account two realistic assumptions. The first one is the fact that in any actual implementation of the continuous variable teleportation protocol (CVTP) Alice and Bob necessarily share non-maximally entangled states (two-mode finitely squeezed states). The second one assumes that Alice's pool of possible coherent states to be teleported to Bob does not cover the whole complex plane (| α | < ∞). The optimal strategy is achieved by tuning three parameters in the original CVTP, namely, Alice's beam splitter transmittance and Bob's displacements in position and momentum implemented on the teleported state. These slight changes in the protocol are currently easy to be implemented and, as we show, give considerable gain in performance for a variety of possible pool of input states with Alice.

  2. Semi-counterfactual cryptography

    NASA Astrophysics Data System (ADS)

    Akshata Shenoy, H.; Srikanth, R.; Srinivas, T.

    2013-09-01

    In counterfactual quantum key distribution (QKD), two remote parties can securely share random polarization-encoded bits through the blocking rather than the transmission of particles. We propose a semi-counterfactual QKD, i.e., one where the secret bit is shared, and also encoded, based on the blocking or non-blocking of a particle. The scheme is thus semi-counterfactual and not based on polarization encoding. As with other counterfactual schemes and the Goldenberg-Vaidman protocol, but unlike BB84, the encoding states are orthogonal and security arises ultimately from single-particle non-locality. Unlike any of them, however, the secret bit generated is maximally indeterminate until the joint action of Alice and Bob. We prove the general security of the protocol, and study the most general photon-number-preserving incoherent attack in detail.

  3. BIAS: Bioinformatics Integrated Application Software.

    PubMed

    Finak, G; Godin, N; Hallett, M; Pepin, F; Rajabi, Z; Srivastava, V; Tang, Z

    2005-04-15

    We introduce a development platform especially tailored to Bioinformatics research and software development. BIAS (Bioinformatics Integrated Application Software) provides the tools necessary for carrying out integrative Bioinformatics research requiring multiple datasets and analysis tools. It follows an object-relational strategy for providing persistent objects, allows third-party tools to be easily incorporated within the system and supports standards and data-exchange protocols common to Bioinformatics. BIAS is an OpenSource project and is freely available to all interested users at http://www.mcb.mcgill.ca/~bias/. This website also contains a paper containing a more detailed description of BIAS and a sample implementation of a Bayesian network approach for the simultaneous prediction of gene regulation events and of mRNA expression from combinations of gene regulation events. hallett@mcb.mcgill.ca.

  4. SSWAP: A Simple Semantic Web Architecture and Protocol for semantic web services

    PubMed Central

    Gessler, Damian DG; Schiltz, Gary S; May, Greg D; Avraham, Shulamit; Town, Christopher D; Grant, David; Nelson, Rex T

    2009-01-01

    Background SSWAP (Simple Semantic Web Architecture and Protocol; pronounced "swap") is an architecture, protocol, and platform for using reasoning to semantically integrate heterogeneous disparate data and services on the web. SSWAP was developed as a hybrid semantic web services technology to overcome limitations found in both pure web service technologies and pure semantic web technologies. Results There are currently over 2400 resources published in SSWAP. Approximately two dozen are custom-written services for QTL (Quantitative Trait Loci) and mapping data for legumes and grasses (grains). The remaining are wrappers to Nucleic Acids Research Database and Web Server entries. As an architecture, SSWAP establishes how clients (users of data, services, and ontologies), providers (suppliers of data, services, and ontologies), and discovery servers (semantic search engines) interact to allow for the description, querying, discovery, invocation, and response of semantic web services. As a protocol, SSWAP provides the vocabulary and semantics to allow clients, providers, and discovery servers to engage in semantic web services. The protocol is based on the W3C-sanctioned first-order description logic language OWL DL. As an open source platform, a discovery server running at (as in to "swap info") uses the description logic reasoner Pellet to integrate semantic resources. The platform hosts an interactive guide to the protocol at , developer tools at , and a portal to third-party ontologies at (a "swap meet"). Conclusion SSWAP addresses the three basic requirements of a semantic web services architecture (i.e., a common syntax, shared semantic, and semantic discovery) while addressing three technology limitations common in distributed service systems: i.e., i) the fatal mutability of traditional interfaces, ii) the rigidity and fragility of static subsumption hierarchies, and iii) the confounding of content, structure, and presentation. SSWAP is novel by establishing the concept of a canonical yet mutable OWL DL graph that allows data and service providers to describe their resources, to allow discovery servers to offer semantically rich search engines, to allow clients to discover and invoke those resources, and to allow providers to respond with semantically tagged data. SSWAP allows for a mix-and-match of terms from both new and legacy third-party ontologies in these graphs. PMID:19775460

  5. Using Third-Party Inspectors in Building Energy Codes Enforcement in India

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yu, Sha; Evans, Meredydd; Kumar, Pradeep

    India is experiencing fast income growth and urbanization, and this leads to unprecedented increases in demand for building energy services and resulting energy consumption. In response to rapid growth in building energy use, the Government of India issued the Energy Conservation Building Code (ECBC) in 2007, which is consistent with and based on the 2001 Energy Conservation Act. ECBC implementation has been voluntary since its enactment and a few states have started to make progress towards mandatory implementation. Rajasthan is the first state in India to adopt ECBC as a mandatory code. The State adopted ECBC with minor additions onmore » March 28, 2011 through a stakeholder process; it became mandatory in Rajasthan on September 28, 2011. Tamil Nadu, Gujarat, and Andhra Pradesh have started to draft an implementation roadmap and build capacity for its implementation. The Bureau of Energy Efficiency (BEE) plans to encourage more states to adopt ECBC in the near future, including Haryana, Uttar Pradesh, Karnataka, Maharashtra, West Bengal, and Delhi. Since its inception, India has applied the code on a voluntary basis, but the Government of India is developing a strategy to mandate compliance. Implementing ECBC requires coordination between the Ministry of Power and the Ministry of Urban Development at the national level as well as interdepartmental coordination at the state level. One challenge is that the Urban Local Bodies (ULBs), the enforcement entities of building by-laws, lack capacity to implement ECBC effectively. For example, ULBs in some states might find the building permitting procedures to be too complex; in other cases, lack of awareness and technical knowledge on ECBC slows down the amendment of local building by-laws as well as ECBC implementation. The intent of this white paper is to share with Indian decision-makers code enforcement approaches: through code officials, third-party inspectors, or a hybrid approach. Given the limited capacity and human resources available in the state and local governments, involving third-party inspectors could rapidly expand the capacity for plan reviews and broad implementation. However, the procedures of involving third-parties need to be carefully designed in order to guarantee a fair process. For example, there should be multiple checks and certification requirements for third-party inspectors, and the government should have the final approval when third-party inspectors are used in a project. This paper discusses different approaches of involving third-parties in ECBC enforcement; the Indian states may choose the approaches that work best in their given circumstances.« less

  6. Adherence to, and outcomes of, a galactomannan screening protocol in high-risk hematology patients.

    PubMed

    Harricharan, S; Biederman, K; Bombassaro, A M; Lazo-Langner, A; Elsayed, S; Fulford, A; Delport, J A; Xenocostas, A

    2018-04-01

    A twice-weekly galactomannan (gm) screening protocol was implemented in high-risk hematology inpatients. Study objectives were to determine adherence to the protocol, use of selected resources, and patient outcomes. This retrospective cohort study compared outcomes of interest before and after implementation of gm screening. Adults undergoing matched related allogeneic hematopoietic stem-cell transplantation or induction chemotherapy for acute leukemia were eligible. Patients could be enrolled more than once and were evaluated as episodes. Adherence to the gm protocol was assessed in post-implementation episodes. Use of broad-spectrum antifungals (bsafs), consultations (infectious diseases, respirology), and diagnostic procedures (computed tomography imaging, bronchoalveolar lavage) were compared between phases, as were the patient outcomes of all-cause mortality and clinical success (alive and not taking a bsaf). Of 182 episodes consecutively screened, 70 per phase were enrolled. Clinical characteristics and duration of assessment were similar for the phases. Full or partial adherence to the protocol was observed in 61 post-implementation episodes (87%), with full adherence in 40 episodes (57%). More episodes in the pre-implementation phase than in the post-implementation phase involved receipt of bsafs, consultations, and diagnostics (27% vs. 7%, p = 0.02; 46% vs. 26%, p = 0.014; and 46% vs. 31%, p = 0.083 respectively). Although mortality was similar in the two phases, clinical success at the final assessment was observed in fewer pre-implementation than post-implementation episodes (79% vs. 98%, p < 0.001). Implementation of a gm screening protocol was feasible and associated with significantly fewer episodes involving receipt of bsafs and consultations, and with significantly more episodes showing clinical success.

  7. Explanation of the Nagoya Protocol on Access and Benefit Sharing and its implication for microbiology.

    PubMed

    Smith, David; da Silva, Manuela; Jackson, Julian; Lyal, Christopher

    2017-03-01

    Working with genetic resources and associated data requires greater attention since the Nagoya Protocol on Access and Benefit Sharing (ABS) came into force in October 2014. Biologists must ensure that they have legal clarity in how they can and cannot use the genetic resources on which they carry out research. Not only must they work within the spirit in the Convention on Biological Diversity (https://www.cbd.int/convention/articles/default.shtml?a=cbd-02) but also they may have regulatory requirements to meet. Although the Nagoya Protocol was negotiated and agreed globally, it is the responsibility of each country that ratifies it to introduce their individual implementing procedures and practices. Many countries in Europe, such as the UK, have chosen not to put access controls in place at this time, but others already have laws enacted providing ABS measures under the Convention on Biological Diversity or specifically to implement the Nagoya Protocol. Access legislation is in place in many countries and information on this can be found at the ABS Clearing House (https://absch.cbd.int/). For example, Brazil, although not a Party to the Nagoya Protocol at the time of writing, has Law 13.123 which entered into force on 17 November 2015, regulated by Decree 8.772 which was published on 11 May 2016. In this case, export of Brazilian genetic resources is not allowed unless the collector is registered in the National System for Genetic Heritage and Associated Traditional Knowledge Management (SisGen). The process entails that a foreign scientist must first of all be registered working with someone in Brazil and have authorization to collect. The enactment of European Union Regulation po. 511/2014 implements Nagoya Protocol elements that govern compliance measures for users and offers the opportunity to demonstrate due diligence in sourcing their organisms by selecting from holdings of 'registered collections'. The UK has introduced a Statutory Instrument that puts in place enforcement measures within the UK to implement this European Union Regulation; this is regulated by Regulatory Delivery, Department for Business, Energy and Industrial Strategies. Scientific communities, including the private sector, individual institutions and organizations, have begun to design policy and best practices for compliance. Microbiologists and culture collections alike need to be aware of the legislation of the source country of the materials they use and put in place best practices for compliance; such best practice has been drafted by the Microbial Resource Research Infrastructure, and other research communities such as the Consortium of European Taxonomic Facilities, the Global Genome Biodiversity Network and the International Organisation for Biological Control have published best practice and/or codes of conduct to ensure legitimate exchange and use of genetic resources.

  8. Implementation of a treaty banning chemical weapons. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ross, S.W.; Sams, D.; Wright, T.

    1991-06-15

    The current rolling text (CD 1046), being negotiated in Geneva by the Conference on Disarmament, calls for the establishment of a Technical Secretariat that would ensure compliance by all State Parties to the treaty through an agreed upon inspection regime. This paper takes the status of CD 1046 and analyzes over 40 National Trial Inspections conducted by individual States of both military and civilian facilities that would be affected by the treaty. It establishes the size; composition; proposed, detailed structure and initial cost of this Technical Secretariat. In addition, it provides a cursory look at the responsibilities of the Preparatorymore » Commission to be formed as a part of the implementation process as well as a National Authority to be established by each State Party. A comparison of two inspection regimes is also presented to evidence that financial implications will not be significantly affected.« less

  9. Evaluation of Secure Computation in a Distributed Healthcare Setting.

    PubMed

    Kimura, Eizen; Hamada, Koki; Kikuchi, Ryo; Chida, Koji; Okamoto, Kazuya; Manabe, Shirou; Kuroda, Tomohiko; Matsumura, Yasushi; Takeda, Toshihiro; Mihara, Naoki

    2016-01-01

    Issues related to ensuring patient privacy and data ownership in clinical repositories prevent the growth of translational research. Previous studies have used an aggregator agent to obscure clinical repositories from the data user, and to ensure the privacy of output using statistical disclosure control. However, there remain several issues that must be considered. One such issue is that a data breach may occur when multiple nodes conspire. Another is that the agent may eavesdrop on or leak a user's queries and their results. We have implemented a secure computing method so that the data used by each party can be kept confidential even if all of the other parties conspire to crack the data. We deployed our implementation at three geographically distributed nodes connected to a high-speed layer two network. The performance of our method, with respect to processing times, suggests suitability for practical use.

  10. Quantum correlations of lights in macroscopic environments

    NASA Astrophysics Data System (ADS)

    Sua, Yong Meng

    This dissertation presents a detailed study in exploring quantum correlations of lights in macroscopic environments. We have explored quantum correlations of single photons, weak coherent states, and polarization-correlated/polarization-entangled photons in macroscopic environments. These included macroscopic mirrors, macroscopic photon number, spatially separated observers, noisy photons source and propagation medium with loss or disturbances. We proposed a measurement scheme for observing quantum correlations and entanglement in the spatial properties of two macroscopic mirrors using single photons spatial compass state. We explored the phase space distribution features of spatial compass states, such as chessboard pattern by using the Wigner function. The displacement and tilt correlations of the two mirrors were manifested through the propensities of the compass states. This technique can be used to extract Einstein-Podolsky-Rosen correlations (EPR) of the two mirrors. We then formulated the discrete-like property of the propensity P b(m,n), which can be used to explore environmental perturbed quantum jumps of the EPR correlations in phase space. With single photons spatial compass state, the variances in position and momentum are much smaller than standard quantum limit when using a Gaussian TEM 00 beam. We observed intrinsic quantum correlations of weak coherent states between two parties through balanced homodyne detection. Our scheme can be used as a supplement to decoy-state BB84 protocol and differential phase-shift QKD protocol. We prepared four types of bipartite correlations +/- cos2(theta1 +/- theta 2) that shared between two parties. We also demonstrated bits correlations between two parties separated by 10 km optical fiber. The bits information will be protected by the large quantum phase fluctuation of weak coherent states, adding another physical layer of security to these protocols for quantum key distribution. Using 10 m of highly nonlinear fiber (HNLF) at 77 K, we observed coincidence to accidental-coincidence ratio of 130+/-5 for correlated photon-pair and Two-Photon Interference visibility >98% entangled photon-pair. We also verified the non-local behavior of polarization-entangled photon pair by violating Clauser-Horne-Shimony-Holt Bell's inequality by more than 12 standard deviations. With the HNLF at 300 K (77 K), photon-pair production rate about factor 3(2) higher than a 300 m dispersion-shifted fiber is observed. Then, we studied quantum correlation and interference of photon-pairs; with one photon of the photon-pair experiencing multiple scattering in a random medium. We observed that depolarization noise photon in multiple scattering degrading the purity of photon-pair, and the existence of Raman noise photon in a photon-pair source will contribute to the depolarization affect. We found that quantum correlation of polarization-entangled photon-pair is better preserved than polarization-correlated photon-pair as one photon of the photon-pair scattered through a random medium. Our findings showed that high purity polarization-entangled photon-pair is better candidate for long distance quantum key distribution.

  11. Interdisciplinary development and implementation of communication checklist for postoperative management of pediatric airway patients.

    PubMed

    Kim, Sang W; Maturo, Stephen; Dwyer, Danielle; Monash, Bradley; Yager, Phoebe H; Zanger, Kerstin; Hartnick, Christopher J

    2012-01-01

    The authors describe their multidisciplinary experience in applying the Institute of Health Improvement methodology to develop a protocol and checklist to reduce communication error during transfer of care for postoperative pediatric surgical airway patients. Preliminary outcome data following implementation of the protocol and checklist are also presented. Prospective study from July 1, 2009, to February 1, 2011. Tertiary care center. Subjects. One hundred twenty-six pediatric airway patients who required coordinated care between Massachusetts Eye and Ear Infirmary and Massachusetts General Hospital. Two sentinel events involving airway emergencies demonstrated a critical need for a standardized, comprehensive instrument that would ensure safe transfer of care. After development and implementation of the protocol and checklist, an initial pilot period on the first set of 9 pediatric airway patients was reassessed. Subsequent prospective 11-month follow-up data of 93 pediatric airway patients were collected and analyzed. A multidisciplinary pediatric team developed and implemented a formalized, postoperative checklist and transfer protocol. After implementation of the checklist and transfer protocol, prospective analysis showed no adverse events from miscommunication during transfer of care over the subsequent 11-month period involving 93 pediatric airway patients. There has been very little written in the quality and safety patient literature about coordinating effective transfer of care between the pediatric surgical and medical subspecialty realms. After design and implementation of a simple, electronically based transfer-of-care checklist and protocol, the number of postsurgical pediatric airway information transfer and communication errors decreased significantly.

  12. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yu, Weikuan; Vetter, Jeffrey S

    Parallel NFS (pNFS) is touted as an emergent standard protocol for parallel I/O access in various storage environments. Several pNFS prototypes have been implemented for initial validation and protocol examination. Previous efforts have focused on realizing the pNFS protocol to expose the best bandwidth potential from underlying file and storage systems. In this presentation, we provide an initial characterization of two pNFS prototype implementations, lpNFS (a Lustre-based parallel NFS implementation) and spNFS (another reference implementation from Network Appliance, Inc.). We show that both lpNFS and spNFS can faithfully achieve the primary goal of pNFS, i.e., aggregating I/O bandwidth from manymore » storage servers. However, they both face the challenge of scalable metadata management. Particularly, the throughput of sp-NFS metadata operations degrades significanlty with an increasing number of data servers. Even for the better-performing lpNFS, we discuss its architecture and propose a direct I/O request flow protocol to improve its performance.« less

  13. 76 FR 74771 - Notice of Implementation of Determination Under Section 129 of the Uruguay Round Agreements Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-01

    ... Department informed interested parties that it was initiating a proceeding under section 129 of the URAA to... FR 77722 (December 27, 2006). The Department invited interested parties to comment on the Preliminary 129 Results. After receiving comments and rebuttal comments from the interested parties, the...

  14. 47 CFR 101.1523 - Sharing and coordination among non-government licensees and between non-government and government...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Wireless Telecommunications Bureau announces by public notice the implementation of a third-party database...) Provide an electronic copy of an interference analysis to the third-party database manager which...-party database managers shall receive and retain the interference analyses electronically and make them...

  15. 47 CFR 101.1523 - Sharing and coordination among non-government licensees and between non-government and government...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Wireless Telecommunications Bureau announces by public notice the implementation of a third-party database...) Provide an electronic copy of an interference analysis to the third-party database manager which...-party database managers shall receive and retain the interference analyses electronically and make them...

  16. 47 CFR 101.1523 - Sharing and coordination among non-government licensees and between non-government and government...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Wireless Telecommunications Bureau announces by public notice the implementation of a third-party database...) Provide an electronic copy of an interference analysis to the third-party database manager which...-party database managers shall receive and retain the interference analyses electronically and make them...

  17. 47 CFR 101.1523 - Sharing and coordination among non-government licensees and between non-government and government...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Wireless Telecommunications Bureau announces by public notice the implementation of a third-party database...) Provide an electronic copy of an interference analysis to the third-party database manager which...-party database managers shall receive and retain the interference analyses electronically and make them...

  18. 47 CFR 101.1523 - Sharing and coordination among non-government licensees and between non-government and government...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Wireless Telecommunications Bureau announces by public notice the implementation of a third-party database...) Provide an electronic copy of an interference analysis to the third-party database manager which...-party database managers shall receive and retain the interference analyses electronically and make them...

  19. Implementation of Symptom Protocols for Nurses Providing Telephone‐Based Cancer Symptom Management: A Comparative Case Study

    PubMed Central

    Green, Esther; Ballantyne, Barbara; Tarasuk, Joy; Skrutkowski, Myriam; Carley, Meg; Chapman, Kim; Kuziemsky, Craig; Kolari, Erin; Sabo, Brenda; Saucier, Andréanne; Shaw, Tara; Tardif, Lucie; Truant, Tracy; Cummings, Greta G.; Howell, Doris

    2016-01-01

    ABSTRACT Background The pan‐Canadian Oncology Symptom Triage and Remote Support (COSTaRS) team developed 13 evidence‐informed protocols for symptom management. Aim To build an effective and sustainable approach for implementing the COSTaRS protocols for nurses providing telephone‐based symptom support to cancer patients. Methods A comparative case study was guided by the Knowledge to Action Framework. Three cases were created for three Canadian oncology programs that have nurses providing telephone support. Teams of researchers and knowledge users: (a) assessed barriers and facilitators influencing protocol use, (b) adapted protocols for local use, (c) intervened to address barriers, (d) monitored use, and (e) assessed barriers and facilitators influencing sustained use. Analysis was within and across cases. Results At baseline, >85% nurses rated protocols positively but barriers were identified (64‐80% needed training). Patients and families identified similar barriers and thought protocols would enhance consistency among nurses teaching self‐management. Twenty‐two COSTaRS workshops reached 85% to 97% of targeted nurses (N = 119). Nurses felt more confident with symptom management and using the COSTaRS protocols (p < .01). Protocol adaptations addressed barriers (e.g., health records approval, creating pocket versions, distributing with telephone messages). Chart audits revealed that protocols used were documented for 11% to 47% of patient calls. Sustained use requires organizational alignment and ongoing leadership support. Linking Evidence to Action Protocol uptake was similar to trials that have evaluated tailored interventions to improve professional practice by overcoming identified barriers. Collaborating with knowledge users facilitated interpretation of findings, aided protocol adaptation, and supported implementation. Protocol implementation in nursing requires a tailored approach. A multifaceted intervention approach increased nurses’ use of evidence‐informed protocols during telephone calls with patients about symptoms. Training and other interventions improved nurses’ confidence with using COSTaRS protocols and their uptake was evident in some documented telephone calls. Protocols could be adapted for use by patients and nurses globally. PMID:27243574

  20. Initial description of primate-specific cystine-knot Prometheus genes and differential gene expansions of D-dopachrome tautomerase genes

    PubMed Central

    Premzl, Marko

    2015-01-01

    Using eutherian comparative genomic analysis protocol and public genomic sequence data sets, the present work attempted to update and revise two gene data sets. The most comprehensive third party annotation gene data sets of eutherian adenohypophysis cystine-knot genes (128 complete coding sequences), and d-dopachrome tautomerases and macrophage migration inhibitory factor genes (30 complete coding sequences) were annotated. For example, the present study first described primate-specific cystine-knot Prometheus genes, as well as differential gene expansions of D-dopachrome tautomerase genes. Furthermore, new frameworks of future experiments of two eutherian gene data sets were proposed. PMID:25941635

  1. A Formative Evaluation of CU-SeeMe.

    DTIC Science & Technology

    1995-02-01

    CU- SeeMe is a video conferencing software package that was designed and programmed at Cornell University. The program works with the TCP/IP network...protocol and allows two or more parties to conduct a real-time video conference with full audio support. In this paper we evaluate CU- SeeMe through...caused the problem and why This helps in the process of formulating solutions for observed usability problems. All the testing results are combined in the Appendix in an illustrated partial redesign of the CU- SeeMe Interface.

  2. Conclusive identification of quantum channels via monogamy of quantum correlations

    NASA Astrophysics Data System (ADS)

    Kumar, Asutosh; Singha Roy, Sudipto; Pal, Amit Kumar; Prabhu, R.; Sen(De), Aditi; Sen, Ujjwal

    2016-10-01

    We investigate the action of global noise and local channels, namely, amplitude-damping, phase-damping, and depolarizing channels, on monogamy of quantum correlations, such as negativity and quantum discord, in three-qubit systems. We discuss the monotonic and non-monotonic variation, and robustness of the monogamy scores. By using monogamy scores, we propose a two-step protocol to conclusively identify the noise applied to the quantum system, by using generalized Greenberger-Horne-Zeilinger and generalized W states as resource states. We discuss a possible generalization of the results to higher number of parties.

  3. Reexamination of quantum bit commitment: The possible and the impossible

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    D'Ariano, Giacomo Mauro; Kretschmann, Dennis; Institut fuer Mathematische Physik, Technische Universitaet Braunschweig, Mendelssohnstrasse 3, 38106 Braunschweig

    2007-09-15

    Bit commitment protocols whose security is based on the laws of quantum mechanics alone are generally held to be impossible. We give a strengthened and explicit proof of this result. We extend its scope to a much larger variety of protocols, which may have an arbitrary number of rounds, in which both classical and quantum information is exchanged, and which may include aborts and resets. Moreover, we do not consider the receiver to be bound to a fixed 'honest' strategy, so that 'anonymous state protocols', which were recently suggested as a possible way to beat the known no-go results, aremore » also covered. We show that any concealing protocol allows the sender to find a cheating strategy, which is universal in the sense that it works against any strategy of the receiver. Moreover, if the concealing property holds only approximately, the cheat goes undetected with a high probability, which we explicitly estimate. The proof uses an explicit formalization of general two-party protocols, which is applicable to more general situations, and an estimate about the continuity of the Stinespring dilation of a general quantum channel. The result also provides a natural characterization of protocols that fall outside the standard setting of unlimited available technology and thus may allow secure bit commitment. We present such a protocol whose security, perhaps surprisingly, relies on decoherence in the receiver's laboratory.« less

  4. [Effect of a multidisciplinar protocol on the clinical results obtained after bariatric surgery].

    PubMed

    Cánovas Gaillemin, B; Sastre Martos, J; Moreno Segura, G; Llamazares Iglesias, O; Familiar Casado, C; Abad de Castro, S; López Pardo, R; Sánchez-Cabezudo Muñoz, M A

    2011-01-01

    Bariatric surgery has been shown to be an effective therapy for weight loss in patients with severe obesity, and the implementation of a multidisciplinar management protocol is recommended. To assess the usefulness of the implementation of a management protocol in obesity surgery based on the Spanish Consensus Document of the SEEDO. Retrospective comparative study of the outcomes in patients previously operated (51 patients) and after the implementation of the protocol (66 patients). The following data were gathered: anthropometry, pre-and post-surgery comorbidities, post-surgical nutritional and surgical complications, validated Quality of Life questionnaire, and dietary habits. Withdrawals (l7.6%) and alcoholism (5.8%) were higher in patients pre- versus post-implementation of the protocol (4.5% vs. 3%, respectively), the differences being statistically significant. The mortality rate was 2% in the pre-protocol group and 0% in the postprotocol group. The dietary habits were better in the post-protocol group, the pre-protocol group presenting a higher percentage of feeding-behavior disorders (5.1%) although not reaching a statistical significance. The improvement in quality of life was higher in the post-protocol group for all items, but only reaching statistical significance in sexual activity (p = 0.004). In the pre-protocol group, 70.5% of the patients had more than one nutritional complication vs. 32.8% in the post-protocol group (p < 0.05). There were no differences regarding the percentage of weight in excess lost at two years (> 50% in 81.3% in the pre-protocol group vs. 74.8% in the pos-protocol group) or the comorbidities. Bariatric surgery achieves excellent outcomes in weight loss, comorbidities, and quality of life, but presents nutritional, surgical, and psychiatric complications that require a protocol-based and multidisciplinary approach. Our protocol improves the outcomes regarding the withdrawal rates, feeding-behavior disorders, dietary habits, nutritional complications, and quality of life.

  5. Timeline of Actions on HFCs

    EPA Pesticide Factsheets

    The Kigali amendment to phase down HFCs was the result of years of negotiation by parties to the Montreal Protocol, with numerous HFC amendment proposals submitted by North America, Island States, India, and the European Union.

  6. Experimentally feasible security check for n-qubit quantum secret sharing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schauer, Stefan; Huber, Marcus; Hiesmayr, Beatrix C.

    In this article we present a general security strategy for quantum secret sharing (QSS) protocols based on the scheme presented by Hillery, Buzek, and Berthiaume (HBB) [Phys. Rev. A 59, 1829 (1999)]. We focus on a generalization of the HBB protocol to n communication parties thus including n-partite Greenberger-Horne-Zeilinger states. We show that the multipartite version of the HBB scheme is insecure in certain settings and impractical when going to large n. To provide security for such QSS schemes in general we use the framework presented by some of the authors [M. Huber, F. Mintert, A. Gabriel, B. C. Hiesmayr,more » Phys. Rev. Lett. 104, 210501 (2010)] to detect certain genuine n-partite entanglement between the communication parties. In particular, we present a simple inequality which tests the security.« less

  7. SSWAP: A Simple Semantic Web Architecture and Protocol for semantic web services.

    PubMed

    Gessler, Damian D G; Schiltz, Gary S; May, Greg D; Avraham, Shulamit; Town, Christopher D; Grant, David; Nelson, Rex T

    2009-09-23

    SSWAP (Simple Semantic Web Architecture and Protocol; pronounced "swap") is an architecture, protocol, and platform for using reasoning to semantically integrate heterogeneous disparate data and services on the web. SSWAP was developed as a hybrid semantic web services technology to overcome limitations found in both pure web service technologies and pure semantic web technologies. There are currently over 2400 resources published in SSWAP. Approximately two dozen are custom-written services for QTL (Quantitative Trait Loci) and mapping data for legumes and grasses (grains). The remaining are wrappers to Nucleic Acids Research Database and Web Server entries. As an architecture, SSWAP establishes how clients (users of data, services, and ontologies), providers (suppliers of data, services, and ontologies), and discovery servers (semantic search engines) interact to allow for the description, querying, discovery, invocation, and response of semantic web services. As a protocol, SSWAP provides the vocabulary and semantics to allow clients, providers, and discovery servers to engage in semantic web services. The protocol is based on the W3C-sanctioned first-order description logic language OWL DL. As an open source platform, a discovery server running at http://sswap.info (as in to "swap info") uses the description logic reasoner Pellet to integrate semantic resources. The platform hosts an interactive guide to the protocol at http://sswap.info/protocol.jsp, developer tools at http://sswap.info/developer.jsp, and a portal to third-party ontologies at http://sswapmeet.sswap.info (a "swap meet"). SSWAP addresses the three basic requirements of a semantic web services architecture (i.e., a common syntax, shared semantic, and semantic discovery) while addressing three technology limitations common in distributed service systems: i.e., i) the fatal mutability of traditional interfaces, ii) the rigidity and fragility of static subsumption hierarchies, and iii) the confounding of content, structure, and presentation. SSWAP is novel by establishing the concept of a canonical yet mutable OWL DL graph that allows data and service providers to describe their resources, to allow discovery servers to offer semantically rich search engines, to allow clients to discover and invoke those resources, and to allow providers to respond with semantically tagged data. SSWAP allows for a mix-and-match of terms from both new and legacy third-party ontologies in these graphs.

  8. Secure authentication protocol for Internet applications over CATV network

    NASA Astrophysics Data System (ADS)

    Chin, Le-Pond

    1998-02-01

    An authentication protocol is proposed in this paper to implement secure functions which include two way authentication and key management between end users and head-end. The protocol can protect transmission from frauds, attacks such as reply and wiretap. Location privacy is also achieved. A rest protocol is designed to restore the system once when systems fail. The security is verified by taking several security and privacy requirements into consideration.

  9. Implementation and Analysis of Real-Time Streaming Protocols.

    PubMed

    Santos-González, Iván; Rivero-García, Alexandra; Molina-Gil, Jezabel; Caballero-Gil, Pino

    2017-04-12

    Communication media have become the primary way of interaction thanks to the discovery and innovation of many new technologies. One of the most widely used communication systems today is video streaming, which is constantly evolving. Such communications are a good alternative to face-to-face meetings, and are therefore very useful for coping with many problems caused by distance. However, they suffer from different issues such as bandwidth limitation, network congestion, energy efficiency, cost, reliability and connectivity. Hence, the quality of service and the quality of experience are considered the two most important issues for this type of communication. This work presents a complete comparative study of two of the most used protocols of video streaming, Real Time Streaming Protocol (RTSP) and the Web Real-Time Communication (WebRTC). In addition, this paper proposes two new mobile applications that implement those protocols in Android whose objective is to know how they are influenced by the aspects that most affect the streaming quality of service, which are the connection establishment time and the stream reception time. The new video streaming applications are also compared with the most popular video streaming applications for Android, and the experimental results of the analysis show that the developed WebRTC implementation improves the performance of the most popular video streaming applications with respect to the stream packet delay.

  10. Threshold quantum cryptography

    NASA Astrophysics Data System (ADS)

    Tokunaga, Yuuki; Okamoto, Tatsuaki; Imoto, Nobuyuki

    2005-01-01

    We present the concept of threshold collaborative unitary transformation or threshold quantum cryptography, which is a kind of quantum version of threshold cryptography. Threshold quantum cryptography states that classical shared secrets are distributed to several parties and a subset of them, whose number is greater than a threshold, collaborates to compute a quantum cryptographic function, while keeping each share secretly inside each party. The shared secrets are reusable if no cheating is detected. As a concrete example of this concept, we show a distributed protocol (with threshold) of conjugate coding.

  11. Financing Solar PV at Government Sites with PPAs and Public Debt (Brochure)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    2011-11-01

    Historically, state and local governmental agencies have employed one of two models to deploy solar photovoltaic (PV) projects: (1) self-ownership (financed through a variety of means) or (2) third-party ownership through a power purchase agreement (PPA). Morris County, New Jersey, administrators recently pioneered a way to combine many of the benefits of self-ownership and third-party PPAs through a bond-PPA hybrid, frequently referred to as the Morris Model. At the request of the Department of Energy's Solar Market Transformation group, NREL examined the hybrid model. This fact sheet describes how the hybrid model works, assesses the model's relative advantages and challengesmore » as compared to self-ownership and the third-party PPA model, provides a quick guide to project implementation, and assesses the replicability of the model in other jurisdictions across the United States.« less

  12. Financing Solar PV at Government Sites with PPAs and Public Debt (Brochure)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    2011-12-01

    Historically, state and local governmental agencies have employed one of two models to deploy solar photovoltaic (PV) projects: (1) self-ownership (financed through a variety of means) or (2) third-party ownership through a power purchase agreement (PPA). Morris County, New Jersey, administrators recently pioneered a way to combine many of the benefits of self-ownership and third-party PPAs through a bond-PPA hybrid, frequently referred to as the Morris Model. At the request of the Department of Energy?s Solar Market Transformation group, NREL examined the hybrid model. This fact sheet describes how the hybrid model works, assesses the model?s relative advantages and challengesmore » as compared to self-ownership and the third-party PPA model, provides a quick guide to project implementation, and assesses the replicability of the model in other jurisdictions across the United States.« less

  13. A model-guided symbolic execution approach for network protocol implementations and vulnerability detection.

    PubMed

    Wen, Shameng; Meng, Qingkun; Feng, Chao; Tang, Chaojing

    2017-01-01

    Formal techniques have been devoted to analyzing whether network protocol specifications violate security policies; however, these methods cannot detect vulnerabilities in the implementations of the network protocols themselves. Symbolic execution can be used to analyze the paths of the network protocol implementations, but for stateful network protocols, it is difficult to reach the deep states of the protocol. This paper proposes a novel model-guided approach to detect vulnerabilities in network protocol implementations. Our method first abstracts a finite state machine (FSM) model, then utilizes the model to guide the symbolic execution. This approach achieves high coverage of both the code and the protocol states. The proposed method is implemented and applied to test numerous real-world network protocol implementations. The experimental results indicate that the proposed method is more effective than traditional fuzzing methods such as SPIKE at detecting vulnerabilities in the deep states of network protocol implementations.

  14. Two-Stage Residual Inclusion Estimation in Health Services Research and Health Economics.

    PubMed

    Terza, Joseph V

    2018-06-01

    Empirical analyses in health services research and health economics often require implementation of nonlinear models whose regressors include one or more endogenous variables-regressors that are correlated with the unobserved random component of the model. In such cases, implementation of conventional regression methods that ignore endogeneity will likely produce results that are biased and not causally interpretable. Terza et al. (2008) discuss a relatively simple estimation method that avoids endogeneity bias and is applicable in a wide variety of nonlinear regression contexts. They call this method two-stage residual inclusion (2SRI). In the present paper, I offer a 2SRI how-to guide for practitioners and a step-by-step protocol that can be implemented with any of the popular statistical or econometric software packages. We introduce the protocol and its Stata implementation in the context of a real data example. Implementation of 2SRI for a very broad class of nonlinear models is then discussed. Additional examples are given. We analyze cigarette smoking as a determinant of infant birthweight using data from Mullahy (1997). It is hoped that the discussion will serve as a practical guide to implementation of the 2SRI protocol for applied researchers. © Health Research and Educational Trust.

  15. Secure data sharing in public cloud

    NASA Astrophysics Data System (ADS)

    Venkataramana, Kanaparti; Naveen Kumar, R.; Tatekalva, Sandhya; Padmavathamma, M.

    2012-04-01

    Secure multi-party protocols have been proposed for entities (organizations or individuals) that don't fully trust each other to share sensitive information. Many types of entities need to collect, analyze, and disseminate data rapidly and accurately, without exposing sensitive information to unauthorized or untrusted parties. Solutions based on secure multiparty computation guarantee privacy and correctness, at an extra communication (too costly in communication to be practical) and computation cost. The high overhead motivates us to extend this SMC to cloud environment which provides large computation and communication capacity which makes SMC to be used between multiple clouds (i.e., it may between private or public or hybrid clouds).Cloud may encompass many high capacity servers which acts as a hosts which participate in computation (IaaS and PaaS) for final result, which is controlled by Cloud Trusted Authority (CTA) for secret sharing within the cloud. The communication between two clouds is controlled by High Level Trusted Authority (HLTA) which is one of the hosts in a cloud which provides MgaaS (Management as a Service). Due to high risk for security in clouds, HLTA generates and distributes public keys and private keys by using Carmichael-R-Prime- RSA algorithm for exchange of private data in SMC between itself and clouds. In cloud, CTA creates Group key for Secure communication between the hosts in cloud based on keys sent by HLTA for exchange of Intermediate values and shares for computation of final result. Since this scheme is extended to be used in clouds( due to high availability and scalability to increase computation power) it is possible to implement SMC practically for privacy preserving in data mining at low cost for the clients.

  16. Entanglement-based Free Space Quantum Cryptography in Daylight

    NASA Astrophysics Data System (ADS)

    Gerhardt, Ilja; Peloso, Matthew P.; Ho, Caleb; Lamas-Linares, Antia; Kurtsiefer, Christian

    2009-05-01

    In quantum key distribution (QKD) two families of protocols are established: One, based on preparing and sending approximations of single photons, the other based on measurements on entangled photon pairs, which allow to establish a secret key using less assumptions on the size of a Hilbert space. The larger optical bandwidth of photon pairs in comparison with light used for the first family makes establishing a free space link challenging. We present a complete entanglement based QKD system following the BBM92 protocol, which generates a secure key continuously 24 hours a day between distant parties. Spectral, spatial and temporal filtering schemes were introduced to a previous setup, suppressing more than 30,B of background. We are able to establish the link during daytime, and have developed an algorithm to start and maintain time synchronization with simple crystal oscillators.

  17. Watermarking protocols for authentication and ownership protection based on timestamps and holograms

    NASA Astrophysics Data System (ADS)

    Dittmann, Jana; Steinebach, Martin; Croce Ferri, Lucilla

    2002-04-01

    Digital watermarking has become an accepted technology for enabling multimedia protection schemes. One problem here is the security of these schemes. Without a suitable framework, watermarks can be replaced and manipulated. We discuss different protocols providing security against rightful ownership attacks and other fraud attempts. We compare the characteristics of existing protocols for different media like direct embedding or seed based and required attributes of the watermarking technology like robustness or payload. We introduce two new media independent protocol schemes for rightful ownership authentication. With the first scheme we ensure security of digital watermarks used for ownership protection with a combination of two watermarks: first watermark of the copyright holder and a second watermark from a Trusted Third Party (TTP). It is based on hologram embedding and the watermark consists of e.g. a company logo. As an example we use digital images and specify the properties of the embedded additional security information. We identify components necessary for the security protocol like timestamp, PKI and cryptographic algorithms. The second scheme is used for authentication. It is designed for invertible watermarking applications which require high data integrity. We combine digital signature schemes and digital watermarking to provide a public verifiable integrity. The original data can only be reproduced with a secret key. Both approaches provide solutions for copyright and authentication watermarking and are introduced for image data but can be easily adopted for video and audio data as well.

  18. Asynchronous Messaging and Data Transfer in a Spacecraft: An Implementation

    NASA Technical Reports Server (NTRS)

    Moholt, Joseph M.

    2005-01-01

    Data transfer and messaging is an important part of a spacecraft. Creating a standard protocol for messaging that can be used for a variety of applications is an extremely beneficial project at the Jet Propulsion Laboratory (JPL). The Asynchronous Messaging Service (AMS) is a protocol outlining how subsystems initialize and conduct communication between each other. There are currently two implementations of AMS in the works. At JPL, my task is to get a working implementation of AMS onto vxWorks as a proof of concept. An Autocoder, a program used to convert visually created state chart diagrams to C++, has also been created to accomplish a part of the implementation. I was assigned to make the program portable on any Unix type environment. Lastly, I was to develop a program to demonstrate messaging between two FireWire cards running vxworks.

  19. Stratospheric ozone, global warming, and the principle of unintended consequences--an ongoing science and policy success story.

    PubMed

    Andersen, Stephen O; Halberstadt, Marcel L; Borgford-Parnell, Nathan

    2013-06-01

    In 1974, Mario Molina and F. Sherwood Rowland warned that chlorofluorocarbons (CFCs) could destroy the stratospheric ozone layer that protects Earth from harmful ultraviolet radiation. In the decade after scientists documented the buildup and long lifetime of CFCs in the atmosphere; found the proof that CFCs chemically decomposed in the stratosphere and catalyzed the depletion of ozone; quantified the adverse effects; and motivated the public and policymakers to take action. In 1987, 24 nations plus the European Community signed the Montreal Protocol. Today, 25 years after the Montreal Protocol was agreed, every United Nations state is a party (universal ratification of 196 governments); all parties are in compliance with the stringent controls; 98% of almost 100 ozone-depleting chemicals have been phased out worldwide; and the stratospheric ozone layer is on its way to recovery by 2065. A growing coalition of nations supports using the Montreal Protocol to phase down hydrofluorocarbons, which are ozone safe but potent greenhouse gases. Without rigorous science and international consensus, emissions of CFCs and related ozone-depleting substances (ODSs) could have destroyed up to two-thirds of the ozone layer by 2065, increasing the risk of causing millions of cancer cases and the potential loss of half of global agricultural production. Furthermore, because most, ODSs are also greenhouse gases, CFCs and related ODSs could have had the effect of the equivalent of 24-76 gigatons per year of carbon dioxide. This critical review describes the history of the science of stratospheric ozone depletion, summarizes the evolution of control measures and compliance under the Montreal Protocol and national legislation, presents a review of six separate transformations over the last 100 years in refrigeration and air conditioning (A/C) technology, and illustrates government-industry cooperation in continually improving the environmental performance of motor vehicle A/C.

  20. Stratospheric ozone, global warming, and the principle of unintended consequences-An ongoing science and policy success story.

    PubMed

    Andersen, Stephen O; Halberstadt, Marcel L; Borgford-Parnell, Nathan

    2013-06-01

    In 1974, Mario Molina and F. Sherwood Rowland warned that chlorofluorocarbons (CFCs) could destroy the stratospheric ozone layer that protects Earth from harmful ultraviolet radiation. In the decade after, scientists documented the buildup and long lifetime of CFCs in the atmosphere; found the proof that CFCs chemically decomposed in the stratosphere and catalyzed the depletion of ozone; quantified the adverse effects; and motivated the public and policymakers to take action. In 1987, 24 nations plus the European Community signed the Montreal Protocol. Today, 25 years after the Montreal Protocol was agreed, every United Nations state is a party (universal ratification of 196 governments); all parties are in compliance with the stringent controls; 98% of almost 100 ozone-depleting chemicals have been phased out worldwide; and the stratospheric ozone layer is on its way to recovery by 2065. A growing coalition of nations supports using the Montreal Protocol to phase down hydrofluorocarbons, which are ozone safe but potent greenhouse gases. Without rigorous science and international consensus, emissions of CFCs and related ozone-depleting substances (ODSs) could have destroyed up to two-thirds of the ozone layer by 2065, increasing the risk of causing millions of cancer cases and the potential loss of half of global agricultural production. Furthermore, because most ODSs are also greenhouse gases, CFCs and related ODSs could have had the effect of the equivalent of 24-76 gigatons per year of carbon dioxide. This critical review describes the history of the science of stratospheric ozone depletion, summarizes the evolution of control measures and compliance under the Montreal Protocol and national legislation, presents a review of six separate transformations over the last 100 years in refrigeration and air conditioning (A/C) technology, and illustrates government-industry cooperation in continually improving the environmental performance of motor vehicle A/C. [Box: see text].

  1. TRUSTBUILDER2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, Adam J.; Perano, Kenneth J.

    In trust negotiation, resource providers specify access control policies in terms of the attributes that should be possessed by authorized users, rather than the identities of these users. Users can prove ownership of certain attributes through the use of digital credentials issued by trusted entities. For example, the Department of Motor Vehicles might issue vehicle owners X.509 driver's licenses that can be used to demonstrate proof of their current age, address, or ability to drive. These types of digital credentials may also be protected by user-specified policies controlling their release to remote parties; for example, Alice might only be willingmore » to show her VISA card credential to members of the Better Business Bureau. In this way, a request to access a given resource can result in a bilateral and iterative exchange of policies and credentials that represents a negotiation between the participating parties. To date, research interest in trust negotiation has been primarily theoretical and any implementations have been largely proofs of concept; experimenting with these prototypes is often not a straightforward task. TrustBuilder2 is a flexible framework for supporting research in the area trust negotiation protocols, designed to allow researchers to quickly prototype and experiment with various approaches to trust negotiation. In TrustBuilder2, the primary components of a trust negotiation system are represented using abstract interfaces.« less

  2. 29 CFR 37.89 - May the Director offer the parties to a complaint the option of mediation?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... of mediation? 37.89 Section 37.89 Labor Office of the Secretary of Labor IMPLEMENTATION OF THE... Procedures § 37.89 May the Director offer the parties to a complaint the option of mediation? Yes. The..., the following rules apply: (a) Mediation is voluntary; the parties must consent before the mediation...

  3. A post-Kyoto partner: Considering the Montreal Protocol as a tool to manage nitrous oxide

    NASA Astrophysics Data System (ADS)

    Mauzerall, D. L.; Kanter, D.; Ravishankara, A. R.; Daniel, J. S.; Portmann, R. W.; Grabiel, P.; Moomaw, W.; Galloway, J. N.

    2012-12-01

    While nitrous oxide (N2O) was recently identified as the largest remaining anthropogenic threat to the stratospheric ozone layer, it is currently regulated under the 1997 Kyoto Protocol due to its simultaneous ability to warm the climate. The threat N2O poses to the stratospheric ozone layer, coupled with the uncertain future of the international climate regime, motivates our exploration of issues that could be relevant to the Parties to the 1987 Montreal Protocol if they decide to take measures to manage N2O in the future. There are clear legal avenues for the Montreal Protocol and its parent treaty, the 1985 Vienna Convention, to regulate N2O, as well as several ways to share authority with the existing and future international climate treaties. N2O mitigation strategies exist to address its most significant anthropogenic sources, including agriculture, where behavioral practices and new technologies could contribute significantly to mitigation efforts. Existing policies managing N2O and other forms of reactive nitrogen could be harnessed and built upon by the Montreal Protocol's existing bodies to implement N2O controls. Given the tight coupling of the nitrogen cycle, such controls would likely simultaneously reduce emissions of reactive nitrogen and hence have co-benefits for ecosystems and public health. Nevertheless, there are at least three major regulatory challenges that are unique and central to N2O control: food security, equity, and the nitrogen cascade. The possible inclusion of N2O in the Montreal Protocol need not be viewed as a sign of the Kyoto Protocol's failure to adequately deal with climate change, given the complexity of the issue. Rather, it could represent an additional tool in the field of sustainable development diplomacy.lt;img border=0 src="images/B43K-06_B.jpg">

  4. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hayashi, A.; Hashimoto, T.; Horibe, M.

    In quantum teleportation, neither Alice nor Bob acquires any classical knowledge on teleported states. The teleportation protocol is said to be oblivious to both parties. In remote state preparation (RSP), it is assumed that Alice is given complete classical knowledge on the state that is to be prepared by Bob. Recently, Leung and Shor [e-print quant-ph/0201008] showed that the same amount of classical information as that in teleportation needs to be transmitted in any exact and deterministic RSP protocol that is oblivious to Bob. Assuming that the dimension of subsystems in the prior-entangled state is the same as the dimensionmore » of the input space, we study similar RSP protocols, but not necessarily oblivious to Bob. We show that in this case Bob's quantum operation can be safely assumed to be a unitary transformation. We then derive an equation that is a necessary and sufficient condition for such a protocol to exist. By studying this equation, we show that one-qubit RSP requires two classical bits of communication, which is the same amount as in teleportation, even if the protocol is not assumed oblivious to Bob. For higher dimensions, it is still an open question whether the amount of classical communication can be reduced by abandoning oblivious conditions.« less

  5. Lightweight CoAP-Based Bootstrapping Service for the Internet of Things.

    PubMed

    Garcia-Carrillo, Dan; Marin-Lopez, Rafael

    2016-03-11

    The Internet of Things (IoT) is becoming increasingly important in several fields of industrial applications and personal applications, such as medical e-health, smart cities, etc. The research into protocols and security aspects related to this area is continuously advancing in making these networks more reliable and secure, taking into account these aspects by design. Bootstrapping is a procedure by which a user obtains key material and configuration information, among other parameters, to operate as an authenticated party in a security domain. Until now solutions have focused on re-using security protocols that were not developed for IoT constraints. For this reason, in this work we propose a design and implementation of a lightweight bootstrapping service for IoT networks that leverages one of the application protocols used in IoT : Constrained Application Protocol (CoAP). Additionally, in order to provide flexibility, scalability, support for large scale deployment, accountability and identity federation, our design uses technologies such as the Extensible Authentication Protocol (EAP) and Authentication Authorization and Accounting (AAA). We have named this service CoAP-EAP. First, we review the state of the art in the field of bootstrapping and specifically for IoT. Second, we detail the bootstrapping service: the architecture with entities and interfaces and the flow operation. Third, we obtain performance measurements of CoAP-EAP (bootstrapping time, memory footprint, message processing time, message length and energy consumption) and compare them with PANATIKI. The most significant and constrained representative of the bootstrapping solutions related with CoAP-EAP. As we will show, our solution provides significant improvements, mainly due to an important reduction of the message length.

  6. Lightweight CoAP-Based Bootstrapping Service for the Internet of Things

    PubMed Central

    Garcia-Carrillo, Dan; Marin-Lopez, Rafael

    2016-01-01

    The Internet of Things (IoT) is becoming increasingly important in several fields of industrial applications and personal applications, such as medical e-health, smart cities, etc. The research into protocols and security aspects related to this area is continuously advancing in making these networks more reliable and secure, taking into account these aspects by design. Bootstrapping is a procedure by which a user obtains key material and configuration information, among other parameters, to operate as an authenticated party in a security domain. Until now solutions have focused on re-using security protocols that were not developed for IoT constraints. For this reason, in this work we propose a design and implementation of a lightweight bootstrapping service for IoT networks that leverages one of the application protocols used in IoT : Constrained Application Protocol (CoAP). Additionally, in order to provide flexibility, scalability, support for large scale deployment, accountability and identity federation, our design uses technologies such as the Extensible Authentication Protocol (EAP) and Authentication Authorization and Accounting (AAA). We have named this service CoAP-EAP. First, we review the state of the art in the field of bootstrapping and specifically for IoT. Second, we detail the bootstrapping service: the architecture with entities and interfaces and the flow operation. Third, we obtain performance measurements of CoAP-EAP (bootstrapping time, memory footprint, message processing time, message length and energy consumption) and compare them with PANATIKI. The most significant and constrained representative of the bootstrapping solutions related with CoAP-EAP. As we will show, our solution provides significant improvements, mainly due to an important reduction of the message length. PMID:26978362

  7. Cryptographic Protocol for Comparing Sets without Leaking Them: Applications in Astronomy

    NASA Astrophysics Data System (ADS)

    McCullough, Peter R.

    2011-09-01

    We describe a cryptographic protocol for two or more persons to compare individual lists of astronomical objects of interest without leaking them. Cryptographers have long known such protocols; astronomers and other scientists may benefit from them also. We describe some latent opportunities that would be enabled by this protocol. Consider the following scenario: Alice has a set of stars that are candidate hosts of transiting planets. Bob has a similar set. Alice and Bob have a mutual desire to know the intersection of their two lists without revealing them to each other. Alice and Bob can recruit a trusted third party, Josephine, to make the comparison, report the results, and then destroy each list. Limitations of that approach are that 1) Josephine must devote time to make each comparison, 2) Alice and Bob may not know a Josephine that they both can trust, especially if Alice and Bob are from different communities, 3) Josephine may not indeed be trustworthy, 4) a fourth person may wittingly or unwittingly intercept one or both of the lists in Josephine's care, and 5) anticipating those limitations, Alice and Bob may elect not to recruit a Josephine and hence not compare their lists. We describe a variant that overcomes those limitations by A) encrypting the lists prior to transmitting them to Josephine, and B) replacing a human Josephine with a computer website.

  8. [Multidisciplinary protocol for computed tomography imaging and angiographic embolization of splenic injury due to trauma: assessment of pre-protocol and post-protocol outcomes].

    PubMed

    Koo, M; Sabaté, A; Magalló, P; García, M A; Domínguez, J; de Lama, M E; López, S

    2011-11-01

    To assess conservative treatment of splenic injury due to trauma, following a protocol for computed tomography (CT) and angiographic embolization. To quantify the predictive value of CT for detecting bleeding and need for embolization. The care protocol developed by the multidisciplinary team consisted of angiography with embolization of lesions revealed by contrast extravasation under CT as well as embolization of grade III-V injuries observed, or grade I-II injuries causing hemodynamic instability and/or need for blood transfusion. We collected data on demographic variables, injury severity score (ISS), angiographic findings, and injuries revealed by CT. Pre-protocol and post-protocol outcomes were compared. The sensitivity and specificity of CT findings were calculated for all patients who required angiographic embolization. Forty-four and 30 angiographies were performed in the pre- and post-protocol periods, respectively. The mean (SD) ISSs in the two periods were 25 (11) and 26 (12), respectively. A total of 24 (54%) embolizations were performed in the pre-protocol period and 28 (98%) after implementation of the protocol. Two and 7 embolizations involved the spleen in the 2 periods, respectively; abdominal laparotomies numbered 32 and 25, respectively, and 10 (31%) vs 4 (16%) splenectomies were performed. The specificity and sensitivity values for contrast extravasation found on CT and followed by embolization were 77.7% and 79.5%. The implementation of this multidisciplinary protocol using CT imaging and angiographic embolization led to a decrease in the number of splenectomies. The protocol allows us to take a more conservative treatment approach.

  9. Comparison of H.323 and SIP for IP telephony signaling

    NASA Astrophysics Data System (ADS)

    Dalgic, Ismail; Fang, Hanlin

    1999-11-01

    Two standards currently compete for the dominance of IP telephony signaling: the H.323 protocol suite by ITU-T, and the Session Initiation Protocol (SIP) by IETF. Both of these signaling protocols provide mechanisms for call establishment and teardown, call control and supplementary services, and capability exchange. We investigate and compare these two protocols in terms of Functionality, Quality of Service (QoS), Scalability, Flexibility, Interoperability, and Ease of Implementation. For fairness of comparison, we consider similar scenarios for both protocols. In particular, we focus on scenarios that involve a gatekeeper for H.323, and a Proxy/Redirect server for SIP. The reason is that medium-to-large IP Telephony systems are not manageable without a gatekeeper or proxy server. We consider all three versions of H.323. In terms of functionality and services that can be supported, H.323 version 2 and SIP are very similar. However, supplementary services in H.323 are more rigorously defined, and therefore fewer interoperability issues are expected among its implementations. Furthermore, H.323 has taken more steps to ensure compatibility among its different versions, and to interoperate with PSTN. The two protocols are comparable in their QoS support [similar call setup delays, no support for resource reservation or class of service (CoS) setting], but H.323 version 3 will allow signaling of the requested CoS. SIP's primary advantages are (1) flexibility to add new features, and (2) relative ease of implementation and debugging. Finally, we note that H.323 and SIP are improving themselves by learning from each other, and the differences between them are diminishing with each new version.

  10. Modeling commodity salam contract between two parties for discrete and continuous time series

    NASA Astrophysics Data System (ADS)

    Hisham, Azie Farhani Badrol; Jaffar, Maheran Mohd

    2017-08-01

    In order for Islamic finance to remain competitive as the conventional, there needs a new development of Islamic compliance product such as Islamic derivative that can be used to manage the risk. However, under syariah principles and regulations, all financial instruments must not be conflicting with five syariah elements which are riba (interest paid), rishwah (corruption), gharar (uncertainty or unnecessary risk), maysir (speculation or gambling) and jahl (taking advantage of the counterparty's ignorance). This study has proposed a traditional Islamic contract namely salam that can be built as an Islamic derivative product. Although a lot of studies has been done on discussing and proposing the implementation of salam contract as the Islamic product however they are more into qualitative and law issues. Since there is lack of quantitative study of salam contract being developed, this study introduces mathematical models that can value the appropriate salam price for a commodity salam contract between two parties. In modeling the commodity salam contract, this study has modified the existing conventional derivative model and come out with some adjustments to comply with syariah rules and regulations. The cost of carry model has been chosen as the foundation to develop the commodity salam model between two parties for discrete and continuous time series. However, the conventional time value of money results from the concept of interest that is prohibited in Islam. Therefore, this study has adopted the idea of Islamic time value of money which is known as the positive time preference, in modeling the commodity salam contract between two parties for discrete and continuous time series.

  11. Lightweight and scalable secure communication in VANET

    NASA Astrophysics Data System (ADS)

    Zhu, Xiaoling; Lu, Yang; Zhu, Xiaojuan; Qiu, Shuwei

    2015-05-01

    To avoid a message to be tempered and forged in vehicular ad hoc network (VANET), the digital signature method is adopted by IEEE1609.2. However, the costs of the method are excessively high for large-scale networks. The paper efficiently copes with the issue with a secure communication framework by introducing some lightweight cryptography primitives. In our framework, point-to-point and broadcast communications for vehicle-to-infrastructure (V2I) and vehicle-to-vehicle (V2V) are studied, mainly based on symmetric cryptography. A new issue incurred is symmetric key management. Thus, we develop key distribution and agreement protocols for two-party key and group key under different environments, whether a road side unit (RSU) is deployed or not. The analysis shows that our protocols provide confidentiality, authentication, perfect forward secrecy, forward secrecy and backward secrecy. The proposed group key agreement protocol especially solves the key leak problem caused by members joining or leaving in existing key agreement protocols. Due to aggregated signature and substitution of XOR for point addition, the average computation and communication costs do not significantly increase with the increase in the number of vehicles; hence, our framework provides good scalability.

  12. Protocol to the African Charter on the Rights of Women: implications for access to abortion at the regional level.

    PubMed

    Ngwena, Charles G

    2010-08-01

    Article 14(2)(c) of the Protocol to the African Charter on the Rights of Women enjoins States Parties to take appropriate measures "to protect the reproductive rights of women by authorising medical abortion in cases of sexual assault, rape, incest, and where continued pregnancy endangers the mental and physical health of the mother or the life of the mother or the foetus." This paper considers the implications of Article 14 for access to safe, legal abortion. It is submitted that Article 14 has the potential to impact positively on regional abortion law, policy, and practice in 3 main areas. First, it takes forward the global consensus on combating abortion as a major public health danger. Second, it provides African countries with not just an incentive, but also an imperative for reforming abortion laws in a transparent manner. Third, if implemented in the context of a treaty that centers on the equality and non-discrimination of women, Article 14 has the potential to contribute toward transforming access to abortion from a crime and punishment model to a reproductive health model. Copyright 2010 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  13. A decentralized software bus based on IP multicas ting

    NASA Technical Reports Server (NTRS)

    Callahan, John R.; Montgomery, Todd

    1995-01-01

    We describe decentralized reconfigurable implementation of a conference management system based on the low-level Internet Protocol (IP) multicasting protocol. IP multicasting allows low-cost, world-wide, two-way transmission of data between large numbers of conferencing participants through the Multicasting Backbone (MBone). Each conference is structured as a software bus -- a messaging system that provides a run-time interconnection model that acts as a separate agent (i.e., the bus) for routing, queuing, and delivering messages between distributed programs. Unlike the client-server interconnection model, the software bus model provides a level of indirection that enhances the flexibility and reconfigurability of a distributed system. Current software bus implementations like POLYLITH, however, rely on a centralized bus process and point-to-point protocols (i.e., TCP/IP) to route, queue, and deliver messages. We implement a software bus called the MULTIBUS that relies on a separate process only for routing and uses a reliable IP multicasting protocol for delivery of messages. The use of multicasting means that interconnections are independent of IP machine addresses. This approach allows reconfiguration of bus participants during system execution without notifying other participants of new IP addresses. The use of IP multicasting also permits an economy of scale in the number of participants. We describe the MULITIBUS protocol elements and show how our implementation performs better than centralized bus implementations.

  14. Experimental temporal quantum steering

    PubMed Central

    Bartkiewicz, Karol; Černoch, Antonín; Lemr, Karel; Miranowicz, Adam; Nori, Franco

    2016-01-01

    Temporal steering is a form of temporal correlation between the initial and final state of a quantum system. It is a temporal analogue of the famous Einstein-Podolsky-Rosen (spatial) steering. We demonstrate, by measuring the photon polarization, that temporal steering allows two parties to verify if they have been interacting with the same particle, even if they have no information about what happened with the particle in between the measurements. This is the first experimental study of temporal steering. We also performed experimental tests, based on the violation of temporal steering inequalities, of the security of two quantum key distribution protocols against individual attacks. Thus, these results can lead to applications for secure quantum communications and quantum engineering. PMID:27901121

  15. Key rate for calibration robust entanglement based BB84 quantum key distribution protocol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gittsovich, O.; Moroder, T.

    2014-12-04

    We apply the approach of verifying entanglement, which is based on the sole knowledge of the dimension of the underlying physical system to the entanglement based version of the BB84 quantum key distribution protocol. We show that the familiar one-way key rate formula holds already if one assumes the assumption that one of the parties is measuring a qubit and no further assumptions about the measurement are needed.

  16. The Achilles' heel of prevention to mother-to-child transmission of HIV: Protocol implementation, uptake, and sustainability.

    PubMed

    Rodriguez, Violeta J; LaCabe, Richard P; Privette, C Kyle; Douglass, K Marie; Peltzer, Karl; Matseke, Gladys; Mathebula, Audrey; Ramlagan, Shandir; Sifunda, Sibusiso; Prado, Guillermo Willy; Horigian, Viviana; Weiss, Stephen M; Jones, Deborah L

    2017-12-01

    The Joint United Nations Programme on HIV and AIDS proposed to reduce the vertical transmission of HIV from ∼72,200 to ∼8300 newly infected children by 2015 in South Africa (SA). However, cultural, infrastructural, and socio-economic barriers hinder the implementation of the prevention of mother-to-child transmission (PMTCT) protocol, and research on potential solutions to address these barriers in rural areas is particularly limited. This study sought to identify challenges and solutions to the implementation, uptake, and sustainability of the PMTCT protocol in rural SA. Forty-eight qualitative interviews, 12 focus groups discussions (n = 75), and one two-day workshop (n = 32 participants) were conducted with district directors, clinic leaders, staff, and patients from 12 rural clinics. The delivery and uptake of the PMTCT protocol was evaluated using the Consolidated Framework for Implementation Research (CFIR); 15 themes associated with challenges and solutions emerged. Intervention characteristics themes included PMTCT training and HIV serostatus disclosure. Outer-setting themes included facility space, health record management, and staff shortage; inner-setting themes included supply use and availability, staff-patient relationship, and transportation and scheduling. Themes related to characteristics of individuals included staff relationships, initial antenatal care visit, adherence, and culture and stigma. Implementation process themes included patient education, test results delivery, and male involvement. Significant gaps in care were identified in rural areas. Information obtained from participants using the CFIR framework provided valuable insights into solutions to barriers to PMTCT implementation. Continuously assessing and correcting PMTCT protocol implementation, uptake and sustainability appear merited to maximize HIV prevention.

  17. The Achilles’ heel of prevention to mother-to-child transmission of HIV: Protocol implementation, uptake, and sustainability

    PubMed Central

    Rodriguez, Violeta J.; LaCabe, Richard P.; Privette, C. Kyle; Douglass, K. Marie; Peltzer, Karl; Matseke, Gladys; Mathebula, Audrey; Ramlagan, Shandir; Sifunda, Sibusiso; Prado, Guillermo “Willy”; Horigian, Viviana; Weiss, Stephen M.; Jones, Deborah L.

    2017-01-01

    Abstract The Joint United Nations Programme on HIV and AIDS proposed to reduce the vertical transmission of HIV from ∼72,200 to ∼8300 newly infected children by 2015 in South Africa (SA). However, cultural, infrastructural, and socio-economic barriers hinder the implementation of the prevention of mother-to-child transmission (PMTCT) protocol, and research on potential solutions to address these barriers in rural areas is particularly limited. This study sought to identify challenges and solutions to the implementation, uptake, and sustainability of the PMTCT protocol in rural SA. Forty-eight qualitative interviews, 12 focus groups discussions (n = 75), and one two-day workshop (n = 32 participants) were conducted with district directors, clinic leaders, staff, and patients from 12 rural clinics. The delivery and uptake of the PMTCT protocol was evaluated using the Consolidated Framework for Implementation Research (CFIR); 15 themes associated with challenges and solutions emerged. Intervention characteristics themes included PMTCT training and HIV serostatus disclosure. Outer-setting themes included facility space, health record management, and staff shortage; inner-setting themes included supply use and availability, staff–patient relationship, and transportation and scheduling. Themes related to characteristics of individuals included staff relationships, initial antenatal care visit, adherence, and culture and stigma. Implementation process themes included patient education, test results delivery, and male involvement. Significant gaps in care were identified in rural areas. Information obtained from participants using the CFIR framework provided valuable insights into solutions to barriers to PMTCT implementation. Continuously assessing and correcting PMTCT protocol implementation, uptake and sustainability appear merited to maximize HIV prevention. PMID:28922974

  18. Implementation and Analysis of Real-Time Streaming Protocols

    PubMed Central

    Santos-González, Iván; Rivero-García, Alexandra; Molina-Gil, Jezabel; Caballero-Gil, Pino

    2017-01-01

    Communication media have become the primary way of interaction thanks to the discovery and innovation of many new technologies. One of the most widely used communication systems today is video streaming, which is constantly evolving. Such communications are a good alternative to face-to-face meetings, and are therefore very useful for coping with many problems caused by distance. However, they suffer from different issues such as bandwidth limitation, network congestion, energy efficiency, cost, reliability and connectivity. Hence, the quality of service and the quality of experience are considered the two most important issues for this type of communication. This work presents a complete comparative study of two of the most used protocols of video streaming, Real Time Streaming Protocol (RTSP) and the Web Real-Time Communication (WebRTC). In addition, this paper proposes two new mobile applications that implement those protocols in Android whose objective is to know how they are influenced by the aspects that most affect the streaming quality of service, which are the connection establishment time and the stream reception time. The new video streaming applications are also compared with the most popular video streaming applications for Android, and the experimental results of the analysis show that the developed WebRTC implementation improves the performance of the most popular video streaming applications with respect to the stream packet delay. PMID:28417949

  19. The Interface of Clinical Decision-Making With Study Protocols for Knowledge Translation From a Walking Recovery Trial.

    PubMed

    Hershberg, Julie A; Rose, Dorian K; Tilson, Julie K; Brutsch, Bettina; Correa, Anita; Gallichio, Joann; McLeod, Molly; Moore, Craig; Wu, Sam; Duncan, Pamela W; Behrman, Andrea L

    2017-01-01

    Despite efforts to translate knowledge into clinical practice, barriers often arise in adapting the strict protocols of a randomized, controlled trial (RCT) to the individual patient. The Locomotor Experience Applied Post-Stroke (LEAPS) RCT demonstrated equal effectiveness of 2 intervention protocols for walking recovery poststroke; both protocols were more effective than usual care physical therapy. The purpose of this article was to provide knowledge-translation tools to facilitate implementation of the LEAPS RCT protocols into clinical practice. Participants from 2 of the trial's intervention arms: (1) early Locomotor Training Program (LTP) and (2) Home Exercise Program (HEP) were chosen for case presentation. The two cases illustrate how the protocols are used in synergy with individual patient presentations and clinical expertise. Decision algorithms and guidelines for progression represent the interface between implementation of an RCT standardized intervention protocol and clinical decision-making. In each case, the participant presents with a distinct clinical challenge that the therapist addresses by integrating the participant's unique presentation with the therapist's expertise while maintaining fidelity to the LEAPS protocol. Both participants progressed through an increasingly challenging intervention despite their own unique presentation. Decision algorithms and exercise progression for the LTP and HEP protocols facilitate translation of the RCT protocol to the real world of clinical practice. The two case examples to facilitate translation of the LEAPS RCT into clinical practice by enhancing understanding of the protocols, their progression, and their application to individual participants.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A147).

  20. PROTOCOL FOR VERIFICATION OF URBAN RUNOFF MODELS

    EPA Science Inventory

    The ETV program was created by the USEPA to accelerate the marketplace acceptance of commercial-ready environmental technologies. This objective will be achieved by conducting credible third-party performance assessments and reporting the results. Access to this data allows users...

  1. Equivalence between entanglement and the optimal fidelity of continuous variable teleportation.

    PubMed

    Adesso, Gerardo; Illuminati, Fabrizio

    2005-10-07

    We devise the optimal form of Gaussian resource states enabling continuous-variable teleportation with maximal fidelity. We show that a nonclassical optimal fidelity of N-user teleportation networks is necessary and sufficient for N-party entangled Gaussian resources, yielding an estimator of multipartite entanglement. The entanglement of teleportation is equivalent to the entanglement of formation in a two-user protocol, and to the localizable entanglement in a multiuser one. Finally, we show that the continuous-variable tangle, quantifying entanglement sharing in three-mode Gaussian states, is defined operationally in terms of the optimal fidelity of a tripartite teleportation network.

  2. Implementation of technology for rapid field detection of sulfate and organic content in soils : technical report.

    DOT National Transportation Integrated Search

    2012-06-01

    The protocol using the Veris 3150 for determination of sulfate-rich soils has been implemented to two fullscale : projects in Dallas and Paris Districts. The determination of organic-rich soil was not implemented in this project : due to the unavaila...

  3. Phase-encoded measurement device independent quantum key distribution without a shared reference frame

    NASA Astrophysics Data System (ADS)

    Zhuo-Dan, Zhu; Shang-Hong, Zhao; Chen, Dong; Ying, Sun

    2018-07-01

    In this paper, a phase-encoded measurement device independent quantum key distribution (MDI-QKD) protocol without a shared reference frame is presented, which can generate secure keys between two parties while the quantum channel or interferometer introduces an unknown and slowly time-varying phase. The corresponding secret key rate and single photons bit error rate is analysed, respectively, with single photons source (SPS) and weak coherent source (WCS), taking finite-key analysis into account. The numerical simulations show that the modified phase-encoded MDI-QKD protocol has apparent superiority both in maximal secure transmission distance and key generation rate while possessing the improved robustness and practical security in the high-speed case. Moreover, the rejection of the frame-calibrating part will intrinsically reduce the consumption of resources as well as the potential security flaws of practical MDI-QKD systems.

  4. Fiber-Optic Terahertz Data-Communication Networks

    NASA Technical Reports Server (NTRS)

    Chua, Peter L.; Lambert, James L.; Morookian, John M.; Bergman, Larry A.

    1994-01-01

    Network protocols implemented in optical domain. Fiber-optic data-communication networks utilize fully available bandwidth of single-mode optical fibers. Two key features of method: use of subpicosecond laser pulses as carrier signals and spectral phase modulation of pulses for optical implementation of code-division multiple access as multiplexing network protocol. Local-area network designed according to concept offers full crossbar functionality, security of data in transit through network, and capacity about 100 times that of typical fiber-optic local-area network in current use.

  5. Key exchange using biometric identity based encryption for sharing encrypted data in cloud environment

    NASA Astrophysics Data System (ADS)

    Hassan, Waleed K.; Al-Assam, Hisham

    2017-05-01

    The main problem associated with using symmetric/ asymmetric keys is how to securely store and exchange the keys between the parties over open networks particularly in the open environment such as cloud computing. Public Key Infrastructure (PKI) have been providing a practical solution for session key exchange for loads of web services. The key limitation of PKI solution is not only the need for a trusted third partly (e.g. certificate authority) but also the absent link between data owner and the encryption keys. The latter is arguably more important where accessing data needs to be linked with identify of the owner. Currently available key exchange protocols depend on using trusted couriers or secure channels, which can be subject to man-in-the-middle attack and various other attacks. This paper proposes a new protocol for Key Exchange using Biometric Identity Based Encryption (KE-BIBE) that enables parties to securely exchange cryptographic keys even an adversary is monitoring the communication channel between the parties. The proposed protocol combines biometrics with IBE in order to provide a secure way to access symmetric keys based on the identity of the users in unsecure environment. In the KE-BIOBE protocol, the message is first encrypted by the data owner using a traditional symmetric key before migrating it to a cloud storage. The symmetric key is then encrypted using public biometrics of the users selected by data owner to decrypt the message based on Fuzzy Identity-Based Encryption. Only the selected users will be able to decrypt the message by providing a fresh sample of their biometric data. The paper argues that the proposed solution eliminates the needs for a key distribution centre in traditional cryptography. It will also give data owner the power of finegrained sharing of encrypted data by control who can access their data.

  6. Electronic Entanglement Concentration for the Concatenated Greenberger-Horne-Zeilinger State

    NASA Astrophysics Data System (ADS)

    Ding, Shang-Ping; Zhou, Lan; Gu, Shi-Pu; Wang, Xing-Fu; Sheng, Yu-Bo

    2017-06-01

    Concatenated Greenberger-Horne-Zeilinger (C-GHZ) state, which encodes many physical qubits in a logic qubit will have important applications in both quantum communication and computation. In this paper, we will describe an entanglement concentration protocol (ECP) for electronic C-GHZ state, by exploiting the electronic polarization beam splitters (PBSs) and charge detection. This protocol has several advantages. First, the parties do not need to know the exact coefficients of the initial less-entangled C-GHZ state, which makes this protocol feasible. Second, with the help of charge detection, the distilled maximally entangled C-GHZ state can be remained for future application. Third, this protocol can be repeated to obtain a higher success probability. We hope that this protocol can be useful in future quantum computation based on electrons.

  7. Managing Threat, Cost, and Incentive to Kill: The Short- and Long-Term Effects of Intervention in Mass Killings

    ERIC Educational Resources Information Center

    Kathman, Jacob D.; Wood, Reed M.

    2011-01-01

    How do third-party interventions affect the severity of mass killings? The authors theorize that episodes of mass killing are the consequence of two factors: (1) the threat perceptions of the perpetrators and (2) the cost of implementing genocidal policies relative to other alternatives. To reduce genocidal hostilities, interveners must address…

  8. Taking stock: protocol for evaluating a family planning supply chain intervention in Senegal.

    PubMed

    Cavallaro, Francesca L; Duclos, Diane; Baggaley, Rebecca F; Penn-Kekana, Loveday; Goodman, Catherine; Vahanian, Alice; Santos, Andreia C; Bradley, John; Paintain, Lucy; Gallien, Jérémie; Gasparrini, Antonio; Hasselback, Leah; Lynch, Caroline A

    2016-04-21

    In Senegal, only 12% of women of reproductive age in union (WRAU) were using contraceptives and another 29% had an unmet need for contraceptives in 2010-11. One potential barrier to accessing contraceptives is the lack of stock availability in health facilities where women seek them. Multiple supply chain interventions have been piloted in low- and middle-income countries with the aim of improving contraceptive availability in health facilities. However, there is limited evidence on the effect of these interventions on contraceptive availability in facilities, and in turn on family planning use in the population. This evaluation protocol pertains to a supply chain intervention using performance-based contracting for contraceptive distribution that was introduced throughout Senegal between 2012 and 2015. This multi-disciplinary research project will include quantitative, qualitative and economic evaluations. Trained researchers in the different disciplines will implement the studies separately but alongside each other, sharing findings throughout the project to inform each other's data collection. A non-randomised study with stepped-wedge design will be used to estimate the effect of the intervention on contraceptive stock availability in health facilities, and on the modern contraceptive prevalence rate among women in Senegal, compared to the current pull-based distribution model used for other commodities. Secondary data from annual Service Provision Assessments and Demographic and Health Surveys will be used for this study. Data on stock availability and monthly family planning consultations over a 4-year period will be collected from 200 health facilities in five regions to perform time series analyses. A process evaluation will be conducted to understand the extent to which the intervention was implemented as originally designed, the acceptability of third-party logisticians within the health system and potential unintended consequences. These will be assessed using monthly indicator data from the implementer and multiple ethnographic methods, including in-depth interviews with key informants and stakeholders at all levels of the distribution system, observations of third-party logisticians and clinic diaries. An economic evaluation will estimate the cost of the intervention, as well as its cost-effectiveness compared to the current supply chain model. Given the very limited evidence base, there is an important need for a comprehensive standardised approach to evaluating supply chain management, and distribution specifically. This evaluation will help address this evidence gap by providing rigorous evidence on whether private performance-based contracting for distribution of contraceptives can contribute to improving access to family planning in low- and middle-income countries.

  9. A Simulation System Based on the Actor Paradigm

    DTIC Science & Technology

    1988-02-01

    of the protocol. Shared memory communication requires the programmer to wait and signal semaphores explicitly to synchronize the communicating parties...wide range of possibilities within the same basic protocol. - The simplicity of the primitive operation set affords those creating new operations...more flexibility (Ada has a large and complicated primitive set). -3- II I I I B A I -I I I I I . 0 1 2 3 4 5 Time 0: Both processes A and B are

  10. A secure distributed logistic regression protocol for the detection of rare adverse drug events

    PubMed Central

    El Emam, Khaled; Samet, Saeed; Arbuckle, Luk; Tamblyn, Robyn; Earle, Craig; Kantarcioglu, Murat

    2013-01-01

    Background There is limited capacity to assess the comparative risks of medications after they enter the market. For rare adverse events, the pooling of data from multiple sources is necessary to have the power and sufficient population heterogeneity to detect differences in safety and effectiveness in genetic, ethnic and clinically defined subpopulations. However, combining datasets from different data custodians or jurisdictions to perform an analysis on the pooled data creates significant privacy concerns that would need to be addressed. Existing protocols for addressing these concerns can result in reduced analysis accuracy and can allow sensitive information to leak. Objective To develop a secure distributed multi-party computation protocol for logistic regression that provides strong privacy guarantees. Methods We developed a secure distributed logistic regression protocol using a single analysis center with multiple sites providing data. A theoretical security analysis demonstrates that the protocol is robust to plausible collusion attacks and does not allow the parties to gain new information from the data that are exchanged among them. The computational performance and accuracy of the protocol were evaluated on simulated datasets. Results The computational performance scales linearly as the dataset sizes increase. The addition of sites results in an exponential growth in computation time. However, for up to five sites, the time is still short and would not affect practical applications. The model parameters are the same as the results on pooled raw data analyzed in SAS, demonstrating high model accuracy. Conclusion The proposed protocol and prototype system would allow the development of logistic regression models in a secure manner without requiring the sharing of personal health information. This can alleviate one of the key barriers to the establishment of large-scale post-marketing surveillance programs. We extended the secure protocol to account for correlations among patients within sites through generalized estimating equations, and to accommodate other link functions by extending it to generalized linear models. PMID:22871397

  11. A secure distributed logistic regression protocol for the detection of rare adverse drug events.

    PubMed

    El Emam, Khaled; Samet, Saeed; Arbuckle, Luk; Tamblyn, Robyn; Earle, Craig; Kantarcioglu, Murat

    2013-05-01

    There is limited capacity to assess the comparative risks of medications after they enter the market. For rare adverse events, the pooling of data from multiple sources is necessary to have the power and sufficient population heterogeneity to detect differences in safety and effectiveness in genetic, ethnic and clinically defined subpopulations. However, combining datasets from different data custodians or jurisdictions to perform an analysis on the pooled data creates significant privacy concerns that would need to be addressed. Existing protocols for addressing these concerns can result in reduced analysis accuracy and can allow sensitive information to leak. To develop a secure distributed multi-party computation protocol for logistic regression that provides strong privacy guarantees. We developed a secure distributed logistic regression protocol using a single analysis center with multiple sites providing data. A theoretical security analysis demonstrates that the protocol is robust to plausible collusion attacks and does not allow the parties to gain new information from the data that are exchanged among them. The computational performance and accuracy of the protocol were evaluated on simulated datasets. The computational performance scales linearly as the dataset sizes increase. The addition of sites results in an exponential growth in computation time. However, for up to five sites, the time is still short and would not affect practical applications. The model parameters are the same as the results on pooled raw data analyzed in SAS, demonstrating high model accuracy. The proposed protocol and prototype system would allow the development of logistic regression models in a secure manner without requiring the sharing of personal health information. This can alleviate one of the key barriers to the establishment of large-scale post-marketing surveillance programs. We extended the secure protocol to account for correlations among patients within sites through generalized estimating equations, and to accommodate other link functions by extending it to generalized linear models.

  12. ENVIRONMENTAL EFFECTS OF OZONE DEPLETION AND ITS INTERACTIONS WITH CLIMATE CHANGE: PROGRESS REPORT 2004

    EPA Science Inventory

    The measures needed for the protection of the Earth's ozone layer are decided regularly by the Parties to the Montreal Protocol. This progress report is the 2004 update by the Environmental Effects Assessment Panel.

  13. Quantum secret sharing with qudit graph states

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Keet, Adrian; Fortescue, Ben; Sanders, Barry C.

    We present a unified formalism for threshold quantum secret sharing using graph states of systems with prime dimension. We construct protocols for three varieties of secret sharing: with classical and quantum secrets shared between parties over both classical and quantum channels.

  14. Increasing the Frequency and Timeliness of Pain Assessment and Management in Long-Term Care: Knowledge Transfer and Sustained Implementation.

    PubMed

    Hadjistavropoulos, Thomas; Williams, Jaime; Kaasalainen, Sharon; Hunter, Paulette V; Savoie, Maryse L; Wickson-Griffiths, Abigail

    2016-01-01

    Background. Although feasible protocols for pain assessment and management in long-term care (LTC) have been developed, these have not been implemented on a large-scale basis. Objective. To implement a program of regular pain assessment in two LTC facilities, using implementation science principles, and to evaluate the process and success of doing so. Methods. The implementation protocol included a pain assessment workshop and the establishment of a nurse Pain Champion. Quality indicators were tracked before and after implementation. Focus groups and interviews with staff were also conducted. Results. The implementation effort was successful in increasing and regularizing pain assessments. This was sustained during the follow-up period. Staff members reported enthusiasm about the protocol at baseline and positive results following its implementation. Despite the success in increasing assessments, we did not identify changes in the percentages of patients reported as having moderate-to-severe pain. Discussion. It is our hope that our feasibility demonstration will encourage more facilities to improve their pain assessment/management practices. Conclusions. It is feasible to implement regular and systematic pain assessment in LTC. Future research should focus on ensuring effective clinical practices in response to assessment results, and determination of longer-term sustainability.

  15. Who needs inpatient detox? Development and implementation of a hospitalist protocol for the evaluation of patients for alcohol detoxification.

    PubMed

    Stephens, John R; Liles, E Allen; Dancel, Ria; Gilchrist, Michael; Kirsch, Jonathan; DeWalt, Darren A

    2014-04-01

    Clinicians caring for patients seeking alcohol detoxification face many challenges, including lack of evidence-based guidelines for treatment and high recidivism rates. To develop a standardized protocol for determining which alcohol dependent patients seeking detoxification need inpatient versus outpatient treatment, and to study the protocol's implementation. Review of best evidence by ad hoc task force and subsequent creation of standardized protocol. Prospective observational evaluation of initial protocol implementation. Patients presenting for alcohol detoxification. Development and implementation of a protocol for evaluation and treatment of patients requesting alcohol detoxification. Number of admissions per month with primary alcohol related diagnosis (DRG), 30-day readmission rate, and length of stay, all measured before and after protocol implementation. We identified one randomized clinical trial and three cohort studies to inform the choice of inpatient versus outpatient detoxification, along with one prior protocol in this population, and combined that data with clinical experience to create an institutional protocol. After implementation, the average number of alcohol related admissions was 15.9 per month, compared with 18.9 per month before implementation (p = 0.037). There was no difference in readmission rate or length of stay. Creation and utilization of a protocol led to standardization of care for patients requesting detoxification from alcohol. Initial evaluation of protocol implementation showed a decrease in number of admissions.

  16. Randomness Amplification under Minimal Fundamental Assumptions on the Devices

    NASA Astrophysics Data System (ADS)

    Ramanathan, Ravishankar; Brandão, Fernando G. S. L.; Horodecki, Karol; Horodecki, Michał; Horodecki, Paweł; Wojewódka, Hanna

    2016-12-01

    Recently, the physically realistic protocol amplifying the randomness of Santha-Vazirani sources producing cryptographically secure random bits was proposed; however, for reasons of practical relevance, the crucial question remained open regarding whether this can be accomplished under the minimal conditions necessary for the task. Namely, is it possible to achieve randomness amplification using only two no-signaling components and in a situation where the violation of a Bell inequality only guarantees that some outcomes of the device for specific inputs exhibit randomness? Here, we solve this question and present a device-independent protocol for randomness amplification of Santha-Vazirani sources using a device consisting of two nonsignaling components. We show that the protocol can amplify any such source that is not fully deterministic into a fully random source while tolerating a constant noise rate and prove the composable security of the protocol against general no-signaling adversaries. Our main innovation is the proof that even the partial randomness certified by the two-party Bell test [a single input-output pair (u* , x* ) for which the conditional probability P (x*|u*) is bounded away from 1 for all no-signaling strategies that optimally violate the Bell inequality] can be used for amplification. We introduce the methodology of a partial tomographic procedure on the empirical statistics obtained in the Bell test that ensures that the outputs constitute a linear min-entropy source of randomness. As a technical novelty that may be of independent interest, we prove that the Santha-Vazirani source satisfies an exponential concentration property given by a recently discovered generalized Chernoff bound.

  17. Blockchain protocols in clinical trials: Transparency and traceability of consent.

    PubMed

    Benchoufi, Mehdi; Porcher, Raphael; Ravaud, Philippe

    2017-01-01

    Clinical trial consent for protocols and their revisions should be transparent for patients and traceable for stakeholders. Our goal is to implement a process allowing for collection of patients' informed consent, which is bound to protocol revisions, storing and tracking the consent in a secure, unfalsifiable and publicly verifiable way, and enabling the sharing of this information in real time. For that, we build a consent workflow using a trending technology called Blockchain. This is a distributed technology that brings a built-in layer of transparency and traceability. From a more general and prospective point of view, we believe Blockchain technology brings a paradigmatical shift to the entire clinical research field. We designed a Proof-of-Concept protocol consisting of time-stamping each step of the patient's consent collection using Blockchain, thus archiving and historicising the consent through cryptographic validation in a securely unfalsifiable and transparent way. For each protocol revision, consent was sought again.  We obtained a single document, in an open format, that accounted for the whole consent collection process: a time-stamped consent status regarding each version of the protocol. This document cannot be corrupted and can be checked on any dedicated public website. It should be considered a robust proof of data. However, in a live clinical trial, the authentication system should be strengthened to remove the need for third parties, here trial stakeholders, and give participative control to the peer users. In the future, the complex data flow of a clinical trial could be tracked by using Blockchain, which core functionality, named Smart Contract, could help prevent clinical trial events not occurring in the correct chronological order, for example including patients before they consented or analysing case report form data before freezing the database. Globally, Blockchain could help with reliability, security, transparency and could be a consistent step toward reproducibility.

  18. Blockchain protocols in clinical trials: Transparency and traceability of consent

    PubMed Central

    Benchoufi, Mehdi; Porcher, Raphael; Ravaud, Philippe

    2018-01-01

    Clinical trial consent for protocols and their revisions should be transparent for patients and traceable for stakeholders. Our goal is to implement a process allowing for collection of patients’ informed consent, which is bound to protocol revisions, storing and tracking the consent in a secure, unfalsifiable and publicly verifiable way, and enabling the sharing of this information in real time. For that, we build a consent workflow using a trending technology called Blockchain. This is a distributed technology that brings a built-in layer of transparency and traceability. From a more general and prospective point of view, we believe Blockchain technology brings a paradigmatical shift to the entire clinical research field. We designed a Proof-of-Concept protocol consisting of time-stamping each step of the patient’s consent collection using Blockchain, thus archiving and historicising the consent through cryptographic validation in a securely unfalsifiable and transparent way. For each protocol revision, consent was sought again.  We obtained a single document, in an open format, that accounted for the whole consent collection process: a time-stamped consent status regarding each version of the protocol. This document cannot be corrupted and can be checked on any dedicated public website. It should be considered a robust proof of data. However, in a live clinical trial, the authentication system should be strengthened to remove the need for third parties, here trial stakeholders, and give participative control to the peer users. In the future, the complex data flow of a clinical trial could be tracked by using Blockchain, which core functionality, named Smart Contract, could help prevent clinical trial events not occurring in the correct chronological order, for example including patients before they consented or analysing case report form data before freezing the database. Globally, Blockchain could help with reliability, security, transparency and could be a consistent step toward reproducibility. PMID:29167732

  19. Enhancing the role of health professionals in the advancement of adolescent sexual health and rights in Africa.

    PubMed

    Kangaude, Godfrey

    2016-01-01

    To realize adolescents' right to sexual health, state parties' implementation of the obligations stipulated under Article 14 of the Protocol to the African Charter on Human and Peoples' Rights on the Rights of Women in Africa should reflect the key principles of the rights of the child, articulated under the Convention on the Rights of the Child and the African Charter on the Welfare and Rights of the Child. However, societal norms that stigmatize adolescent sexual conduct constitute barriers to adolescents' sexual health care, including their access to contraceptives to avoid unwanted pregnancies and protect themselves from STIs and HIV. States should sensitize and train health professionals to provide sexual health services and care in accordance with the principles of the rights of the child, and create enabling laws and policies to facilitate their work with adolescents. Copyright © 2015. Published by Elsevier Ireland Ltd.

  20. Chapter 7: Refrigerator Recycling Evaluation Protocol. The Uniform Methods Project: Methods for Determining Energy-Efficiency Savings for Specific Measures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kurnik, Charles W.; Keeling, Josh; Bruchs, Doug

    Refrigerator recycling programs are designed to save energy by removing operable, albeit less efficient, refrigerators from service. By offering free pickup, providing incentives, and disseminating information about the operating cost of less efficient refrigerators, these programs are designed to encourage consumers to: - Limit the use of secondary refrigerators -Relinquish refrigerators previously used as primary units when they are replaced (rather than keeping the existing refrigerator as a secondary unit) -Prevent the continued use of less efficient refrigerators in another household through a direct transfer (giving it away or selling it) or indirect transfer (resale on the used appliance market).more » Commonly implemented by third-party contractors (who collect and decommission participating appliances), these programs generate energy savings through the retirement of inefficient appliances. The decommissioning process captures environmentally harmful refrigerants and foam, and enables recycling of the plastic, metal, and wiring components.« less

  1. Pharmaceutical care for patients with COPD in Belgium and views on protocol implementation.

    PubMed

    Tommelein, Eline; Tollenaere, Kathleen; Mehuys, Els; Boussery, Koen

    2014-08-01

    A protocol-based pharmaceutical care program (the PHARMACOP-protocol) focusing on patient counselling during prescription filling has shown to be effective in patients with chronic obstructive pulmonary disease (COPD). However, implementation of this protocol in daily practice has not yet been studied. To describe current implementation level of the items included in the PHARMACOP-protocol in Belgian community pharmacies and to evaluate pharmacists' perspectives on the implementation of this protocol in daily practice. A cross-sectional study was conducted from April to June 2012, in randomly selected community pharmacies in Flanders. Pharmacists were questionned using structured interviews. 125 pharmacies were contacted and 80 managing pharmacists (64 %) participated. In >70 % of pharmacies, 4/7 protocol items for first prescriptions and 3/5 protocol items for follow-up prescriptions were already routinely implemented. For first and follow-up prescriptions, respectively 39 (49 %) and 34 pharmacists (43 %) stated they would need to spend at least 5 min extra to offer optimal patient counselling. Most mentioned barriers preventing protocol implementation included lack of time (80 %), no integration in pharmacy software (61 %) and too much administrative burden (58 %). Approximately 50 % of the PHARMACOP-protocol items are currently routinely provided in Belgian community pharmacies. Nearly all interviewed pharmacists are willing to implement the protocol fully or partially in daily practice.

  2. Instituting a music listening intervention for critically ill patients receiving mechanical ventilation: Exemplars from two patient cases

    PubMed Central

    Heiderscheit, Annie; Chlan, Linda; Donley, Kim

    2011-01-01

    Music is an ideal intervention to reduce anxiety and promote relaxation in critically ill patients receiving mechanical ventilatory support. This article reviews the basis for a music listening intervention and describes two case examples with patients utilizing a music listening intervention to illustrate the implementation and use of the music listening protocol in this dynamic environment. The case examples illustrate the importance and necessity of engaging a music therapist in not only assessing the music preferences of patients, but also for implementing a music listening protocol to manage the varied and challenging needs of patients in the critical care setting. Additionally, the case examples presented in this paper demonstrate the wide array of music patients prefer and how the ease of a music listening protocol allows mechanically ventilated patients to engage in managing their own anxiety during this distressful experience. PMID:22081788

  3. [Analysis of palliative sedation in hospitalised elderly patients: Effectiveness of a protocol].

    PubMed

    Mateos-Nozal, Jesús; García-Cabrera, Lorena; Montero Errasquín, Beatriz; Cruz-Jentoft, Alfonso José; Rexach Cano, Lourdes

    2016-01-01

    To measure changes in the practice of palliative sedation during agony in hospitalised elderly patients before and after the implementation of a palliative sedation protocol. A retrospective before-after study was performed in hospitalised patients over 65 years old who received midazolam during hospital admission and died in the hospital in two 3-month periods, before and after the implementation of the protocol. Non-sedative uses of midazolam and patients in intensive care were excluded. Patient and admission characteristics, the consent process, withdrawal of life-sustaining treatments, and the sedation process (refractory symptom treated, drug doses, assessment and use of other drugs) were recorded. Association was analysed using the Chi(2) and Student t tests. A total of 143 patients were included, with no significant differences between groups in demographic characteristics or symptoms. Do not resuscitate (DNR) orders were recorded in approximately 70% of the subjects of each group, and informed consent for sedation was recorded in 91% before vs. 84% after the protocol. Induction and maintenance doses of midazolam followed protocol recommendations in 1.3% before vs 10.4% after the protocol was implemented (P=.02) and adequate rescue doses were used in 1.3% vs 11.9% respectively (P=.01). Midazolam doses were significantly lower (9.86mg vs 18.67mg, P<.001) when the protocol was used than when it was not used. Ramsay sedation score was used in 8% vs. 12% and the Palliative Care Team was involved in 35.5% and 16.4% of the cases (P=.008) before and after the protocol, respectively. Use of midazolam slightly improved after the implementation of a hospital protocol on palliative sedation. The percentage of adequate sedations and the general process of sedation were mostly unchanged by the protocol. More education and further assessment is needed to gauge the effect of these measures in the future. Copyright © 2015 SEGG. Published by Elsevier Espana. All rights reserved.

  4. Noise effects on entanglement distribution by separable state

    NASA Astrophysics Data System (ADS)

    Bordbar, Najmeh Tabe; Memarzadeh, Laleh

    2018-02-01

    We investigate noise effects on the performance of entanglement distribution by separable state. We consider a realistic situation in which the mediating particle between two distant nodes of the network goes through a noisy channel. For a large class of noise models, we show that the average value of distributed entanglement between two parties is equal to entanglement between particular bipartite partitions of target qubits and exchange qubit in intermediate steps of the protocol. This result is valid for distributing two-qubit/qudit and three-qubit entangled states. In explicit examples of the noise family, we show that there exists a critical value of noise parameter beyond which distribution of distillable entanglement is not possible. Furthermore, we determine how this critical value increases in terms of Hilbert space dimension, when distributing d-dimensional Bell states.

  5. Concurrent remote entanglement with quantum error correction against photon losses

    NASA Astrophysics Data System (ADS)

    Roy, Ananda; Stone, A. Douglas; Jiang, Liang

    2016-09-01

    Remote entanglement of distant, noninteracting quantum entities is a key primitive for quantum information processing. We present a protocol to remotely entangle two stationary qubits by first entangling them with propagating ancilla qubits and then performing a joint two-qubit measurement on the ancillas. Subsequently, single-qubit measurements are performed on each of the ancillas. We describe two continuous variable implementations of the protocol using propagating microwave modes. The first implementation uses propagating Schr o ̈ dinger cat states as the flying ancilla qubits, a joint-photon-number-modulo-2 measurement of the propagating modes for the two-qubit measurement, and homodyne detections as the final single-qubit measurements. The presence of inefficiencies in realistic quantum systems limit the success rate of generating high fidelity Bell states. This motivates us to propose a second continuous variable implementation, where we use quantum error correction to suppress the decoherence due to photon loss to first order. To that end, we encode the ancilla qubits in superpositions of Schrödinger cat states of a given photon-number parity, use a joint-photon-number-modulo-4 measurement as the two-qubit measurement, and homodyne detections as the final single-qubit measurements. We demonstrate the resilience of our quantum-error-correcting remote entanglement scheme to imperfections. Further, we describe a modification of our error-correcting scheme by incorporating additional individual photon-number-modulo-2 measurements of the ancilla modes to improve the success rate of generating high-fidelity Bell states. Our protocols can be straightforwardly implemented in state-of-the-art superconducting circuit-QED systems.

  6. The Use of Efficient Broadcast Protocols in Asynchronous Distributed Systems. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Schmuck, Frank Bernhard

    1988-01-01

    Reliable broadcast protocols are important tools in distributed and fault-tolerant programming. They are useful for sharing information and for maintaining replicated data in a distributed system. However, a wide range of such protocols has been proposed. These protocols differ in their fault tolerance and delivery ordering characteristics. There is a tradeoff between the cost of a broadcast protocol and how much ordering it provides. It is, therefore, desirable to employ protocols that support only a low degree of ordering whenever possible. This dissertation presents techniques for deciding how strongly ordered a protocol is necessary to solve a given application problem. It is shown that there are two distinct classes of application problems: problems that can be solved with efficient, asynchronous protocols, and problems that require global ordering. The concept of a linearization function that maps partially ordered sets of events to totally ordered histories is introduced. How to construct an asynchronous implementation that solves a given problem if a linearization function for it can be found is shown. It is proved that in general the question of whether a problem has an asynchronous solution is undecidable. Hence there exists no general algorithm that would automatically construct a suitable linearization function for a given problem. Therefore, an important subclass of problems that have certain commutativity properties are considered. Techniques for constructing asynchronous implementations for this class are presented. These techniques are useful for constructing efficient asynchronous implementations for a broad range of practical problems.

  7. Multiparty Quantum Key Agreement Based on Quantum Search Algorithm

    PubMed Central

    Cao, Hao; Ma, Wenping

    2017-01-01

    Quantum key agreement is an important topic that the shared key must be negotiated equally by all participants, and any nontrivial subset of participants cannot fully determine the shared key. To date, the embed modes of subkey in all the previously proposed quantum key agreement protocols are based on either BB84 or entangled states. The research of the quantum key agreement protocol based on quantum search algorithms is still blank. In this paper, on the basis of investigating the properties of quantum search algorithms, we propose the first quantum key agreement protocol whose embed mode of subkey is based on a quantum search algorithm known as Grover’s algorithm. A novel example of protocols with 5 – party is presented. The efficiency analysis shows that our protocol is prior to existing MQKA protocols. Furthermore it is secure against both external attack and internal attacks. PMID:28332610

  8. Security of two quantum cryptography protocols using the same four qubit states

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Branciard, Cyril; Ecole Nationale Superieure des Telecommunications, 46, rue Barrault, 75013 Paris; Gisin, Nicolas

    2005-09-15

    The first quantum cryptography protocol, proposed by Bennett and Brassard in 1984 (BB84), has been widely studied in recent years. This protocol uses four states (more precisely, two complementary bases) for the encoding of the classical bit. Recently, it has been noticed that by using the same four states, but a different encoding of information, one can define a protocol which is more robust in practical implementations, specifically when attenuated laser pulses are used instead of single-photon sources [V. Scarani et al., Phys. Rev. Lett. 92, 057901 (2004), referred to as the SARG04 protocol]. We present a detailed study ofmore » SARG04 in two different regimes. In the first part, we consider an implementation with a single-photon source: we derive bounds on the error rate Q for security against all possible attacks by the eavesdropper. The lower and the upper bound obtained for SARG04 (Q < or approx. 10.95% and Q > or approx. 14.9%, respectively) are close to those obtained for BB84 (Q < or approx. 12.4% and Q > or approx. 14.6%, respectively). In the second part, we consider a realistic source consisting of an attenuated laser and improve on previous analysis by allowing Alice to optimize the mean number of photons as a function of the distance. The SARG04 protocol is found to perform better than BB84, both in secret-key rate and in maximal achievable distance, for a wide class of Eve's attacks.« less

  9. Southeast Asia Report No. 1323, Vietnam Tap Chi Cong San No. 6, June 1983

    DTIC Science & Technology

    1983-08-10

    safety in every situation, implement the mechanism "the party leads, the people exercise ownership and the state manages" well and have an intense...scientific-technological research and training cadres. The outskirts of the city have been expanded. The majority of the people of Hanoi are urban cadres...economy and the standard of living, the party organization and people of Hanoi have made many efforts to implement the lines, positions and policies of

  10. Private randomness expansion with untrusted devices

    NASA Astrophysics Data System (ADS)

    Colbeck, Roger; Kent, Adrian

    2011-03-01

    Randomness is an important resource for many applications, from gambling to secure communication. However, guaranteeing that the output from a candidate random source could not have been predicted by an outside party is a challenging task, and many supposedly random sources used today provide no such guarantee. Quantum solutions to this problem exist, for example a device which internally sends a photon through a beamsplitter and observes on which side it emerges, but, presently, such solutions require the user to trust the internal workings of the device. Here, we seek to go beyond this limitation by asking whether randomness can be generated using untrusted devices—even ones created by an adversarial agent—while providing a guarantee that no outside party (including the agent) can predict it. Since this is easily seen to be impossible unless the user has an initially private random string, the task we investigate here is private randomness expansion. We introduce a protocol for private randomness expansion with untrusted devices which is designed to take as input an initially private random string and produce as output a longer private random string. We point out that private randomness expansion protocols are generally vulnerable to attacks that can render the initial string partially insecure, even though that string is used only inside a secure laboratory; our protocol is designed to remove this previously unconsidered vulnerability by privacy amplification. We also discuss extensions of our protocol designed to generate an arbitrarily long random string from a finite initially private random string. The security of these protocols against the most general attacks is left as an open question.

  11. 5 CFR 2634.407 - Restrictions on fiduciaries and interested parties.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... ETHICS EXECUTIVE BRANCH FINANCIAL DISCLOSURE, QUALIFIED TRUSTS, AND CERTIFICATES OF DIVESTITURE Qualified... instrument; (2) Acquire any holding: (i) Directly from an interested party without the prior written approval... of the Act, the implementing regulations, the trust instrument, or with other applicable statutes and...

  12. "Party Line" Information Use Studies and Implications for ATC Datalink Communications

    NASA Technical Reports Server (NTRS)

    Hansman, R. John; Pritchett, Amy; Midkiff, Alan

    1995-01-01

    The perceived importance and utilization of 'party line' information by air carrier flight crews was investigated through pilot surveys and a flight simulation study. The importance, availability, and accuracy of party line information elements were explored through surveys of pilots of several operational types. The survey identified numerous traffic and weather party line information elements which were considered important. These elements were scripted into a full-mission flight simulation which examined the utilization of party line information by studying subject responses to specific information element stimuli. The awareness of the different Party Line elements varied, and awareness was also affected by pilot workload. In addition, pilots were aware of some traffic information elements, but were reluctant to act on Party Line Information alone. Finally, the results of both the survey and the simulation indicated that the importance of party line information appeared to be greatest for operations near or on the airport. This indicates that caution should be exercised when implementing datalink communications in tower and close-in terminal control sectors.

  13. 'Party Line' Information Use Studies and Implications for ATV Datalink Communications

    NASA Technical Reports Server (NTRS)

    Pritchett, Amy; Hansman, R. John; Midkiff, Alan

    1995-01-01

    The perceived importance and utilization of 'party line' information by air carrier flight crews was investigated through pilot surveys and a flight simulation study. The Importance, Availability, and Accuracy of party line information elements were explored through surveys of pilots of several operational types. The survey identified numerous traffic and weather party line information elements which were considered important. These elements were scripted into a full-mission flight simulation which examined the utilization of party line information by studying subject responses to specific information element stimuli. The awareness of the different Party Line elements varied, and awareness was also affected by pilot workload. In addition, pilots were aware of some traffic information elements, but were reluctant to act on Party Line Information alone. Finally, the importance of party line information appears to be greatest for operations near or on the airport. This indicates that caution should be exercised when implementing datalink communications in tower and close-in terminal control sectors.

  14. Modelling the dynamics of two political parties in the presence of switching.

    PubMed

    Nyabadza, F; Alassey, Tobge Yawo; Muchatibaya, Gift

    2016-01-01

    This paper generalizes the model proposed by Misra, by considering switching between political parties. In the model proposed, the movements of members from political party B to political party C and vice versa, are considered but the net movement is considered by assuming that [Formula: see text] (a constant), which implies that the movement of members is either from party B to party C or from party C to party B. In this paper we remodel these movements through switching functions to capture how individuals switch between parties. The results provide a more comprehensive synopsis of the dynamics between two political parties.

  15. Exploring the Implementation of Steganography Protocols on Quantum Audio Signals

    NASA Astrophysics Data System (ADS)

    Chen, Kehan; Yan, Fei; Iliyasu, Abdullah M.; Zhao, Jianping

    2018-02-01

    Two quantum audio steganography (QAS) protocols are proposed, each of which manipulates or modifies the least significant qubit (LSQb) of the host quantum audio signal that is encoded as an FRQA (flexible representation of quantum audio) audio content. The first protocol (i.e. the conventional LSQb QAS protocol or simply the cLSQ stego protocol) is built on the exchanges between qubits encoding the quantum audio message and the LSQb of the amplitude information in the host quantum audio samples. In the second protocol, the embedding procedure to realize it implants information from a quantum audio message deep into the constraint-imposed most significant qubit (MSQb) of the host quantum audio samples, we refer to it as the pseudo MSQb QAS protocol or simply the pMSQ stego protocol. The cLSQ stego protocol is designed to guarantee high imperceptibility between the host quantum audio and its stego version, whereas the pMSQ stego protocol ensures that the resulting stego quantum audio signal is better immune to illicit tampering and copyright violations (a.k.a. robustness). Built on the circuit model of quantum computation, the circuit networks to execute the embedding and extraction algorithms of both QAS protocols are determined and simulation-based experiments are conducted to demonstrate their implementation. Outcomes attest that both protocols offer promising trade-offs in terms of imperceptibility and robustness.

  16. Experimental realization of counterfactual quantum cryptography Experimental realization of counterfactual quantum cryptography

    NASA Astrophysics Data System (ADS)

    Brida, G.; Cavanna, A.; Degiovanni, I. P.; Genovese, M.; Traina, P.

    2012-03-01

    In counterfactual quantum key distribution (CQKD) information is transferred, in a secure way, between Alice and Bob even when no particle carrying the information is in fact transmitted between them. In this letter we fully implement the scheme for CQKD proposed in [1], demonstrating for the first time that information can be transmitted between two parties without the transmission of a carrier.

  17. The Counterinsurgency Policies of the Hindu Nationalist Bharatiya Janata Party of India and the Naxalite Insurgency

    DTIC Science & Technology

    2016-12-01

    amnesty. The government is allocating needed resources to implement its strategy effectively. In the last two years, Naxalite violence has decreased...Naxalite violence has decreased, although the government still faces many challenges such as coordinating efforts and controlling corruption and other...90 Table 4. State-wise Extent of LWE Violence during 2011 to 2016 (up to October 15, 2016

  18. Quantum cryptography: Theoretical protocols for quantum key distribution and tests of selected commercial QKD systems in commercial fiber networks

    NASA Astrophysics Data System (ADS)

    Jacak, Monika; Jacak, Janusz; Jóźwiak, Piotr; Jóźwiak, Ireneusz

    2016-06-01

    The overview of the current status of quantum cryptography is given in regard to quantum key distribution (QKD) protocols, implemented both on nonentangled and entangled flying qubits. Two commercial R&D platforms of QKD systems are described (the Clavis II platform by idQuantique implemented on nonentangled photons and the EPR S405 Quelle platform by AIT based on entangled photons) and tested for feasibility of their usage in commercial TELECOM fiber metropolitan networks. The comparison of systems efficiency, stability and resistivity against noise and hacker attacks is given with some suggestion toward system improvement, along with assessment of two models of QKD.

  19. Practical decoy state for quantum key distribution

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ma Xiongfeng; Qi Bing; Zhao Yi

    2005-07-15

    Decoy states have recently been proposed as a useful method for substantially improving the performance of quantum key distribution (QKD). Here, we present a general theory of the decoy state protocol based on only two decoy states and one signal state. We perform optimization on the choice of intensities of the two decoy states and the signal state. Our result shows that a decoy state protocol with only two types of decoy states - the vacuum and a weak decoy state - asymptotically approaches the theoretical limit of the most general type of decoy state protocol (with an infinite numbermore » of decoy states). We also present a one-decoy-state protocol. Moreover, we provide estimations on the effects of statistical fluctuations and suggest that, even for long-distance (larger than 100 km) QKD, our two-decoy-state protocol can be implemented with only a few hours of experimental data. In conclusion, decoy state quantum key distribution is highly practical.« less

  20. 75 FR 65214 - Equal Access to Justice Act Implementation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-22

    ... the Director of FHFA until such regulations are modified, terminated, set aside, or superseded by.... Director means the Director of the Federal Housing Finance Agency. Fees and other expenses includes... for remuneration for the party, under the party's direction and control. Part-time employees must be...

  1. 18 CFR 33.2 - Contents of application-general information requirements.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... post-transaction corporate structures (including any pending authorized but not implemented changes... that the proposed transaction does not affect the corporate structure of any party to the transaction... application); (5) The identity of common officers or directors of parties to the proposed transaction (to be...

  2. 18 CFR 33.2 - Contents of application-general information requirements.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... post-transaction corporate structures (including any pending authorized but not implemented changes... that the proposed transaction does not affect the corporate structure of any party to the transaction... application); (5) The identity of common officers or directors of parties to the proposed transaction (to be...

  3. 18 CFR 33.2 - Contents of application-general information requirements.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... post-transaction corporate structures (including any pending authorized but not implemented changes... that the proposed transaction does not affect the corporate structure of any party to the transaction... application); (5) The identity of common officers or directors of parties to the proposed transaction (to be...

  4. 18 CFR 33.2 - Contents of application-general information requirements.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... post-transaction corporate structures (including any pending authorized but not implemented changes... that the proposed transaction does not affect the corporate structure of any party to the transaction... application); (5) The identity of common officers or directors of parties to the proposed transaction (to be...

  5. A Model Based Security Testing Method for Protocol Implementation

    PubMed Central

    Fu, Yu Long; Xin, Xiao Long

    2014-01-01

    The security of protocol implementation is important and hard to be verified. Since the penetration testing is usually based on the experience of the security tester and the specific protocol specifications, a formal and automatic verification method is always required. In this paper, we propose an extended model of IOLTS to describe the legal roles and intruders of security protocol implementations, and then combine them together to generate the suitable test cases to verify the security of protocol implementation. PMID:25105163

  6. A model based security testing method for protocol implementation.

    PubMed

    Fu, Yu Long; Xin, Xiao Long

    2014-01-01

    The security of protocol implementation is important and hard to be verified. Since the penetration testing is usually based on the experience of the security tester and the specific protocol specifications, a formal and automatic verification method is always required. In this paper, we propose an extended model of IOLTS to describe the legal roles and intruders of security protocol implementations, and then combine them together to generate the suitable test cases to verify the security of protocol implementation.

  7. Implementation of Quantum Private Queries Using Nuclear Magnetic Resonance

    NASA Astrophysics Data System (ADS)

    Wang, Chuan; Hao, Liang; Zhao, Lian-Jie

    2011-08-01

    We present a modified protocol for the realization of a quantum private query process on a classical database. Using one-qubit query and CNOT operation, the query process can be realized in a two-mode database. In the query process, the data privacy is preserved as the sender would not reveal any information about the database besides her query information, and the database provider cannot retain any information about the query. We implement the quantum private query protocol in a nuclear magnetic resonance system. The density matrix of the memory registers are constructed.

  8. Occupational health nursing interventions to reduce third-party liability in workplace injuries.

    PubMed

    Delk, Kayla L

    2012-03-01

    This article explores general principles of workers' compensation law and the ability to sue third parties for employee injuries by using case law and the treatise Larson's Workers' Compensation Law. This overview provides occupational health nurses with a background on workers' compensation law, who is liable for employee injuries, and how recovery from third parties is distributed between the employer or insurer and the employee. The author then explores interventions that occupational health nurses can implement to reduce employee injury and employer costs for providing workers' compensation. The goal of this article is to stimulate occupational health nurses' critical-thinking and problem-solving skills so they may identify risks and implement cost-effective solutions that will prevent injuries to employees. Copyright 2012, SLACK Incorporated.

  9. Translations on North Korea. Number 509

    DTIC Science & Technology

    1977-02-16

    forward a Wise agricultural policy and guided all farming work one by one. Sin In-chol, a member of the "Chongmaek Association" and student in Seoul...same time, find out and ascertain as normal procedure the status of enforcing the party’s agricultural policy and the state of all farm work. They...must intensify party guidance and control so that the great leader’s instructions and the party’s agricultural policy are accurately implemented and

  10. 15 CFR 785.8 - Discovery.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 2 2011-01-01 2011-01-01 false Discovery. 785.8 Section 785.8... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE ADDITIONAL PROTOCOL REGULATIONS ENFORCEMENT § 785.8 Discovery. (a) General. The parties are encouraged to engage in voluntary discovery regarding any matter, not...

  11. 15 CFR 785.8 - Discovery.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 2 2012-01-01 2012-01-01 false Discovery. 785.8 Section 785.8... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE ADDITIONAL PROTOCOL REGULATIONS ENFORCEMENT § 785.8 Discovery. (a) General. The parties are encouraged to engage in voluntary discovery regarding any matter, not...

  12. 15 CFR 785.8 - Discovery.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 2 2013-01-01 2013-01-01 false Discovery. 785.8 Section 785.8... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE ADDITIONAL PROTOCOL REGULATIONS ENFORCEMENT § 785.8 Discovery. (a) General. The parties are encouraged to engage in voluntary discovery regarding any matter, not...

  13. 15 CFR 785.8 - Discovery.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 2 2014-01-01 2014-01-01 false Discovery. 785.8 Section 785.8... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE ADDITIONAL PROTOCOL REGULATIONS ENFORCEMENT § 785.8 Discovery. (a) General. The parties are encouraged to engage in voluntary discovery regarding any matter, not...

  14. 15 CFR 785.8 - Discovery.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Discovery. 785.8 Section 785.8... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE ADDITIONAL PROTOCOL REGULATIONS ENFORCEMENT § 785.8 Discovery. (a) General. The parties are encouraged to engage in voluntary discovery regarding any matter, not...

  15. Joint ETV/NOWATECH verification protocol for the Sorbisense GSW40 passive sampler

    EPA Science Inventory

    Environmental technology verification (ETV) is an independent (third party) assessment of the performance of a technology or a product for a specified application, under defined conditions and quality assurance. This verification is a joint verification with the US EPA ETV schem...

  16. An investigation into the nutritional status of patients receiving an Enhanced Recovery After Surgery (ERAS) protocol versus standard care following Oesophagectomy.

    PubMed

    Benton, Katie; Thomson, Iain; Isenring, Elisabeth; Mark Smithers, B; Agarwal, Ekta

    2018-06-01

    Enhanced Recovery After Surgery (ERAS) protocols have been effectively expanded to various surgical specialities including oesophagectomy. Despite nutrition being a key component, actual nutrition outcomes and specific guidelines are lacking. This cohort comparison study aims to compare nutritional status and adherence during implementation of a standardised post-operative nutritional support protocol, as part of ERAS, compared to those who received usual care. Two groups of patients undergoing resection of oesophageal cancer were studied. Group 1 (n = 17) underwent oesophagectomy between Oct 2014 and Nov 2016 during implementation of an ERAS protocol. Patients in group 2 (n = 16) underwent oesophagectomy between Jan 2011 and Dec 2012 prior to the implementation of ERAS. Demographic, nutritional status, dietary intake and adherence data were collected. Ordinal data was analysed using independent t tests, and categorical data using chi-square tests. There was no significant difference in nutrition status, dietary intake or length of stay following implementation of an ERAS protocol. Malnutrition remained prevalent in both groups at day 42 post surgery (n = 10, 83% usual care; and n = 9, 60% ERAS). A significant difference was demonstrated in adherence with earlier initiation of oral free fluids (p <0.008), transition to soft diet (p <0.004) and continuation of jejunostomy feeds on discharge (p <0.000) for the ERAS group. A standardised post-operative nutrition protocol, within an ERAS framework, results in earlier transition to oral intake; however, malnutrition remains prevalent post surgery. Further large-scale studies are warranted to examine individualised decision-making regarding nutrition support within an ERAS protocol.

  17. The Data Party: Involving Stakeholders in Meaningful Data Analysis

    ERIC Educational Resources Information Center

    Franz, Nancy K.

    2013-01-01

    A hallmark of Extension includes the involvement of stakeholders in research and program needs assessment, design, implementation, evaluation, and reporting. A data party can be used to enhance this stakeholder involvement specifically in data analysis. This type of event can not only increase client participation in Extension programming and…

  18. 31 CFR 16.17 - Rights of parties.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance: Treasury 1 2012-07-01 2012-07-01 false Rights of parties. 16.17 Section 16.17 Money and Finance: Treasury Office of the Secretary of the Treasury REGULATIONS IMPLEMENTING THE...; and (h) Submit written beliefs and proposed findings of fact and conclusions of law after the hearing. ...

  19. 31 CFR 16.17 - Rights of parties.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance: Treasury 1 2013-07-01 2013-07-01 false Rights of parties. 16.17 Section 16.17 Money and Finance: Treasury Office of the Secretary of the Treasury REGULATIONS IMPLEMENTING THE...; and (h) Submit written beliefs and proposed findings of fact and conclusions of law after the hearing. ...

  20. 31 CFR 16.17 - Rights of parties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Rights of parties. 16.17 Section 16.17 Money and Finance: Treasury Office of the Secretary of the Treasury REGULATIONS IMPLEMENTING THE...; and (h) Submit written beliefs and proposed findings of fact and conclusions of law after the hearing. ...

  1. 31 CFR 16.17 - Rights of parties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance: Treasury 1 2011-07-01 2011-07-01 false Rights of parties. 16.17 Section 16.17 Money and Finance: Treasury Office of the Secretary of the Treasury REGULATIONS IMPLEMENTING THE...; and (h) Submit written beliefs and proposed findings of fact and conclusions of law after the hearing. ...

  2. 31 CFR 16.17 - Rights of parties.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance: Treasury 1 2014-07-01 2014-07-01 false Rights of parties. 16.17 Section 16.17 Money and Finance: Treasury Office of the Secretary of the Treasury REGULATIONS IMPLEMENTING THE...; and (h) Submit written beliefs and proposed findings of fact and conclusions of law after the hearing. ...

  3. 78 FR 10136 - Magnuson-Stevens Act Provisions; Fisheries of the Northeastern United States; Northeast...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-13

    .... NE multispecies sectors are required to design and implement independent, third-party at-sea... NE Multispecies Fishery Management Plan (Amendment 16) require third-party monitoring service... in order to be eligible to provide dockside and/or at-sea monitoring services to sectors. ADDRESSES...

  4. Megahertz-Rate Semi-Device-Independent Quantum Random Number Generators Based on Unambiguous State Discrimination

    NASA Astrophysics Data System (ADS)

    Brask, Jonatan Bohr; Martin, Anthony; Esposito, William; Houlmann, Raphael; Bowles, Joseph; Zbinden, Hugo; Brunner, Nicolas

    2017-05-01

    An approach to quantum random number generation based on unambiguous quantum state discrimination is developed. We consider a prepare-and-measure protocol, where two nonorthogonal quantum states can be prepared, and a measurement device aims at unambiguously discriminating between them. Because the states are nonorthogonal, this necessarily leads to a minimal rate of inconclusive events whose occurrence must be genuinely random and which provide the randomness source that we exploit. Our protocol is semi-device-independent in the sense that the output entropy can be lower bounded based on experimental data and a few general assumptions about the setup alone. It is also practically relevant, which we demonstrate by realizing a simple optical implementation, achieving rates of 16.5 Mbits /s . Combining ease of implementation, a high rate, and a real-time entropy estimation, our protocol represents a promising approach intermediate between fully device-independent protocols and commercial quantum random number generators.

  5. Design, Implementation, and Verification of the Reliable Multicast Protocol. Thesis

    NASA Technical Reports Server (NTRS)

    Montgomery, Todd L.

    1995-01-01

    This document describes the Reliable Multicast Protocol (RMP) design, first implementation, and formal verification. RMP provides a totally ordered, reliable, atomic multicast service on top of an unreliable multicast datagram service. RMP is fully and symmetrically distributed so that no site bears an undue portion of the communications load. RMP provides a wide range of guarantees, from unreliable delivery to totally ordered delivery, to K-resilient, majority resilient, and totally resilient atomic delivery. These guarantees are selectable on a per message basis. RMP provides many communication options, including virtual synchrony, a publisher/subscriber model of message delivery, a client/server model of delivery, mutually exclusive handlers for messages, and mutually exclusive locks. It has been commonly believed that total ordering of messages can only be achieved at great performance expense. RMP discounts this. The first implementation of RMP has been shown to provide high throughput performance on Local Area Networks (LAN). For two or more destinations a single LAN, RMP provides higher throughput than any other protocol that does not use multicast or broadcast technology. The design, implementation, and verification activities of RMP have occurred concurrently. This has allowed the verification to maintain a high fidelity between design model, implementation model, and the verification model. The restrictions of implementation have influenced the design earlier than in normal sequential approaches. The protocol as a whole has matured smoother by the inclusion of several different perspectives into the product development.

  6. Visual grading characteristics and ordinal regression analysis during optimisation of CT head examinations.

    PubMed

    Zarb, Francis; McEntee, Mark F; Rainford, Louise

    2015-06-01

    To evaluate visual grading characteristics (VGC) and ordinal regression analysis during head CT optimisation as a potential alternative to visual grading assessment (VGA), traditionally employed to score anatomical visualisation. Patient images (n = 66) were obtained using current and optimised imaging protocols from two CT suites: a 16-slice scanner at the national Maltese centre for trauma and a 64-slice scanner in a private centre. Local resident radiologists (n = 6) performed VGA followed by VGC and ordinal regression analysis. VGC alone indicated that optimised protocols had similar image quality as current protocols. Ordinal logistic regression analysis provided an in-depth evaluation, criterion by criterion allowing the selective implementation of the protocols. The local radiology review panel supported the implementation of optimised protocols for brain CT examinations (including trauma) in one centre, achieving radiation dose reductions ranging from 24 % to 36 %. In the second centre a 29 % reduction in radiation dose was achieved for follow-up cases. The combined use of VGC and ordinal logistic regression analysis led to clinical decisions being taken on the implementation of the optimised protocols. This improved method of image quality analysis provided the evidence to support imaging protocol optimisation, resulting in significant radiation dose savings. • There is need for scientifically based image quality evaluation during CT optimisation. • VGC and ordinal regression analysis in combination led to better informed clinical decisions. • VGC and ordinal regression analysis led to dose reductions without compromising diagnostic efficacy.

  7. ENVIRONMENTAL EFFECTS OF OZONE DEPLETION AND ITS INTERACTIONS WITH CLIMATE CHANGE: PROGRESS REPORT 2003

    EPA Science Inventory

    The measures needed for the protection of the Earth's ozone layer are decided regularly by the Parties to the Montreal Protocol. A section of this progress report focuses on the interactive effects of climate change and ozone depletion on biogeochemical cycles.

  8. MetaSeq: privacy preserving meta-analysis of sequencing-based association studies.

    PubMed

    Singh, Angad Pal; Zafer, Samreen; Pe'er, Itsik

    2013-01-01

    Human genetics recently transitioned from GWAS to studies based on NGS data. For GWAS, small effects dictated large sample sizes, typically made possible through meta-analysis by exchanging summary statistics across consortia. NGS studies groupwise-test for association of multiple potentially-causal alleles along each gene. They are subject to similar power constraints and therefore likely to resort to meta-analysis as well. The problem arises when considering privacy of the genetic information during the data-exchange process. Many scoring schemes for NGS association rely on the frequency of each variant thus requiring the exchange of identity of the sequenced variant. As such variants are often rare, potentially revealing the identity of their carriers and jeopardizing privacy. We have thus developed MetaSeq, a protocol for meta-analysis of genome-wide sequencing data by multiple collaborating parties, scoring association for rare variants pooled per gene across all parties. We tackle the challenge of tallying frequency counts of rare, sequenced alleles, for metaanalysis of sequencing data without disclosing the allele identity and counts, thereby protecting sample identity. This apparent paradoxical exchange of information is achieved through cryptographic means. The key idea is that parties encrypt identity of genes and variants. When they transfer information about frequency counts in cases and controls, the exchanged data does not convey the identity of a mutation and therefore does not expose carrier identity. The exchange relies on a 3rd party, trusted to follow the protocol although not trusted to learn about the raw data. We show applicability of this method to publicly available exome-sequencing data from multiple studies, simulating phenotypic information for powerful meta-analysis. The MetaSeq software is publicly available as open source.

  9. Face-to-Face versus Computer-Mediated Discussion of Teaching Cases: Impacts on Preservice Teachers' Engagement, Critical Analyses, and Self-Efficacy

    ERIC Educational Resources Information Center

    PytlikZillig, Lisa M.; Horn, Christy A.; Bruning, Roger; Bell, Stephanie; Liu, Xiongyi; Siwatu, Kamau O.; Bodvarsson, Mary C.; Kim, Doyoung; Carlson, Deborah

    2011-01-01

    Two frequently-used discussion protocols were investigated as part of a program to implement teaching cases in undergraduate educational psychology classes designed for preservice teachers. One protocol involved synchronous face-to-face (FTF) discussion of teaching cases, which occurred in class after students had individually completed written…

  10. A Simple XML Producer-Consumer Protocol

    NASA Technical Reports Server (NTRS)

    Smith, Warren; Gunter, Dan; Quesnel, Darcy

    2000-01-01

    This document describes a simple XML-based protocol that can be used for producers of events to communicate with consumers of events. The protocol described here is not meant to be the most efficient protocol, the most logical protocol, or the best protocol in any way. This protocol was defined quickly and it's intent is to give us a reasonable protocol that we can implement relatively easily and then use to gain experience in distributed event services. This experience will help us evaluate proposals for event representations, XML-based encoding of information, and communication protocols. The next section of this document describes how we represent events in this protocol and then defines the two events that we choose to use for our initial experiments. These definitions are made by example so that they are informal and easy to understand. The following section then proceeds to define the producer-consumer protocol we have agreed upon for our initial experiments.

  11. Department of Energy Efforts to Promote Universal Adherence to the IAEA Additional Protocol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Killinger, Mark H.; Hansen, Linda H.; Kovacic, Don N.

    2009-10-06

    Entry-into-force of the U.S. Additional Protocol (AP) in January 2009 continues to demonstrate the ongoing commitment by the United States to promote universal adherence to the AP. The AP is a critical tool for improving the International Atomic Energy Agency’s (IAEA) capabilities to detect undeclared activities that indicate a clandestine nuclear weapons program. This is because States Parties are required to provide information about, and access to, nuclear fuel cycle activities beyond their traditional safeguards reporting requirements. As part of the U.S. AP Implementation Act and Senate Resolution of Ratification, the Administration is required to report annually to Congress onmore » measures taken to achieve the adoption of the AP in non-nuclear weapon states, as well as assistance to the IAEA to promote the effective implementation of APs in those states. A key U.S. effort in this area is being managed by the International Nuclear Safeguards and Engagement Program (INSEP) of the U.S. Department of Energy (DOE). Through new and existing bilateral cooperation agreements, INSEP has initiated technical assistance projects for AP implementation with selected non-weapon states. States with which INSEP is currently cooperating include Vietnam and Thailand, with Indonesia, Algeria, Morocco, and other countries as possible future collaborators in the area of AP implementation. The INSEP collaborative model begins with a joint assessment with our partners to identify specific needs they may have regarding entering the AP into force and any impediments to successful implementation. An action plan is then developed detailing and prioritizing the necessary joint activities. Such assistance may include: advice on developing legal frameworks and regulatory documents; workshops to promote understanding of AP requirements; training to determine possible declarable activities; assistance in developing a system to collect and submit declarations; performing industry outreach to raise awareness; guidance for reporting export and manufacturing of “especially designed or prepared” equipment listed in AP Annex I/Annex II; and lastly, developing indigenous capabilities to sustain AP implementation. INSEP also coordinates with the IAEA to ensure the harmonization of the assistance provided by DOE and the IAEA. This paper describes current efforts and future plans for AP international implementation support.« less

  12. Who will attack the competitors? How political parties resolve strategic and collective action dilemmas in negative campaigning

    PubMed Central

    Dolezal, Martin; Müller, Wolfgang C

    2015-01-01

    Negative campaigning presents parties with a collective action problem. While parties would prefer to have their competitors attacked, potential backlash effects from negative messages mean that individual politicians typically lack the incentives to carry out such attacks. We theorize that parties solve this problem by implementing a division of labour that takes into account the incentives of individual office holders, their availability for campaign activity, and media relevance. Drawing on these arguments we expect that holders of high public office and party leaders are less likely to issue attacks, leaving the bulk of the ‘dirty work’ to be carried out by party floor leaders and general secretaries. Examining almost 8000 press releases issued by over 600 individual politicians during four election campaigns in Austria, we find strong support for our theoretical expectations. PMID:28989298

  13. Attacks exploiting deviation of mean photon number in quantum key distribution and coin tossing

    NASA Astrophysics Data System (ADS)

    Sajeed, Shihan; Radchenko, Igor; Kaiser, Sarah; Bourgoin, Jean-Philippe; Pappa, Anna; Monat, Laurent; Legré, Matthieu; Makarov, Vadim

    2015-03-01

    The security of quantum communication using a weak coherent source requires an accurate knowledge of the source's mean photon number. Finite calibration precision or an active manipulation by an attacker may cause the actual emitted photon number to deviate from the known value. We model effects of this deviation on the security of three quantum communication protocols: the Bennett-Brassard 1984 (BB84) quantum key distribution (QKD) protocol without decoy states, Scarani-Acín-Ribordy-Gisin 2004 (SARG04) QKD protocol, and a coin-tossing protocol. For QKD we model both a strong attack using technology possible in principle and a realistic attack bounded by today's technology. To maintain the mean photon number in two-way systems, such as plug-and-play and relativistic quantum cryptography schemes, bright pulse energy incoming from the communication channel must be monitored. Implementation of a monitoring detector has largely been ignored so far, except for ID Quantique's commercial QKD system Clavis2. We scrutinize this implementation for security problems and show that designing a hack-proof pulse-energy-measuring detector is far from trivial. Indeed, the first implementation has three serious flaws confirmed experimentally, each of which may be exploited in a cleverly constructed Trojan-horse attack. We discuss requirements for a loophole-free implementation of the monitoring detector.

  14. Department of Energy WindSentinel Loan Program Description

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shaw, William J.; Sturges, Mark H.

    The U.S. Department of Energy (DOE) currently owns two AXYS WindSentinel buoys that collect a comprehensive set of meteorological and oceanographic data to support resource characterization for wind energy offshore. The two buoys were delivered to DOE’s Pacific Northwest National Laboratory (PNNL) in September, 2014. After acceptance testing and initial performance testing and evaluation at PNNL’s Marine Sciences Laboratory in Sequim, Washington, the buoys have been deployed off the U.S. East Coast. One buoy was deployed approximately 42 km east of Virginia Beach, Virginia from December, 2014 through June, 2016. The second buoy was deployed approximately 5 km off Atlanticmore » City, New Jersey in November, 2015. Data from the buoys are available to the public. Interested parties can create an account and log in to http://offshoreweb.pnnl.gov. In response to a number of inquiries and unsolicited proposals, DOE’s Wind Energy Technologies Office is implementing a program, to be managed by PNNL, to lend the buoys to qualified parties for the purpose of acquiring wind resource characterization data in areas of interest for offshore wind energy development. This document describes the buoys, the scope of the loans, the process of how borrowers will be selected, and the schedule for implementation of this program, including completing current deployments.« less

  15. Protecting Privacy and Securing the Gathering of Location Proofs - The Secure Location Verification Proof Gathering Protocol

    NASA Astrophysics Data System (ADS)

    Graham, Michelle; Gray, David

    As wireless networks become increasingly ubiquitous, the demand for a method of locating a device has increased dramatically. Location Based Services are now commonplace but there are few methods of verifying or guaranteeing a location provided by a user without some specialised hardware, especially in larger scale networks. We propose a system for the verification of location claims, using proof gathered from neighbouring devices. In this paper we introduce a protocol to protect this proof gathering process, protecting the privacy of all involved parties and securing it from intruders and malicious claiming devices. We present the protocol in stages, extending the security of this protocol to allow for flexibility within its application. The Secure Location Verification Proof Gathering Protocol (SLVPGP) has been designed to function within the area of Vehicular Networks, although its application could be extended to any device with wireless & cryptographic capabilities.

  16. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lim, Charles Ci Wen; Xu, Feihu; Siopsis, George

    Quantum position verification (QPV) is the art of verifying the geographical location of an untrusted party. It has recently been shown that the widely studied Bennett & Brassard 1984 (BB84) QPV protocol is insecure after the 3 dB loss point assuming local operations and classical communication (LOCC) adversaries. Here in this paper, we propose a time-reversed entanglement swapping QPV protocol (based on measurement-device-independent quantum cryptography) that is highly robust against quantum channel loss. First, assuming ideal qubit sources, we show that the protocol is secure against LOCC adversaries for any quantum channel loss, thereby overcoming the 3 dB loss limit.more » Then, we analyze the security of the protocol in a more practical setting involving weak laser sources and linear optics. Lastly, in this setting, we find that the security only degrades by an additive constant and the protocol is able to verify positions up to 47 dB channel loss.« less

  17. Loss-tolerant quantum secure positioning with weak laser sources

    NASA Astrophysics Data System (ADS)

    Lim, Charles Ci Wen; Xu, Feihu; Siopsis, George; Chitambar, Eric; Evans, Philip G.; Qi, Bing

    2016-09-01

    Quantum position verification (QPV) is the art of verifying the geographical location of an untrusted party. Recently, it has been shown that the widely studied Bennett & Brassard 1984 (BB84) QPV protocol is insecure after the 3 dB loss point assuming local operations and classical communication (LOCC) adversaries. Here, we propose a time-reversed entanglement swapping QPV protocol (based on measurement-device-independent quantum cryptography) that is highly robust against quantum channel loss. First, assuming ideal qubit sources, we show that the protocol is secure against LOCC adversaries for any quantum channel loss, thereby overcoming the 3 dB loss limit. Then, we analyze the security of the protocol in a more practical setting involving weak laser sources and linear optics. In this setting, we find that the security only degrades by an additive constant and the protocol is able to verify positions up to 47 dB channel loss.

  18. Domestic Implementation of a Chemical Weapons Treaty

    DTIC Science & Technology

    1989-10-01

    regulations can be used for treaty comliance; identify producers of certain treaty chemicals and present case studies on two such chemicals; review and...discuss the protocol limitations of using existing statutes for the reporting requirements through case studies of two chemicals for which reporting...requirements or requ.lations can be used to facilitate domestic implementation, studies the domestic implmentation procedures and experience gained fron the

  19. Implementation of safety checklists in surgery: a realist synthesis of evidence.

    PubMed

    Gillespie, Brigid M; Marshall, Andrea

    2015-09-28

    The aim of this review is to present a realist synthesis of the evidence of implementation interventions to improve adherence to the use of safety checklists in surgery. Surgical safety checklists have been shown to improve teamwork and patient safety in the operating room. Yet, despite the benefits associated with their use, universal implementation of and compliance with these checklists has been inconsistent. An overview of the literature from 2008 is examined in relation to checklist implementation, compliance, and sustainability. Pawson's and Rycroft-Malone's realist synthesis methodology was used to explain the interaction between context, mechanism, and outcome. This approach incorporated the following: defining the scope of the review, searching and appraising the evidence, extracting and synthesising the findings, and disseminating, implementing, and evaluating the evidence. We identified two theories a priori that explained contextual nuances associated with implementation and evaluation of checklists in surgery: the Normalisation Process Theory and Responsive Regulation Theory. We identified four a priori propositions: (1) Checklist protocols that are prospectively tailored to the context are more likely to be used and sustained in practice, (2) Fidelity and sustainability is increased when checklist protocols can be seamlessly integrated into daily professional practice, (3) Routine embedding of checklist protocols in practice is influenced by factors that promote or inhibit clinicians' participation, and (4) Regulation reinforcement mechanisms that are more contextually responsive should lead to greater compliance in using checklist protocols. The final explanatory model suggests that the sustained use of surgical checklists is discipline-specific and is more likely to occur when medical staff are actively engaged and leading the process of implementation. Involving clinicians in tailoring the checklist to better fit their context of practice and giving them the opportunity to reflect and evaluate the implementation intervention enables greater participation and ownership of the process. A major limitation in the surgical checklist literature is the lack of robust descriptions of intervention methods and implementation strategies. Despite this, two consequential findings have emerged through this realist synthesis: First, the sustained use of surgical checklists is discipline-specific and is more successful when physicians are actively engaged and leading implementation. Second, involving clinicians in tailoring the checklist to their context and encouraging them to reflect on and evaluate the implementation process enables greater participation and ownership.

  20. General Approach to Quantum Channel Impossibility by Local Operations and Classical Communication.

    PubMed

    Cohen, Scott M

    2017-01-13

    We describe a general approach to proving the impossibility of implementing a quantum channel by local operations and classical communication (LOCC), even with an infinite number of rounds, and find that this can often be demonstrated by solving a set of linear equations. The method also allows one to design a LOCC protocol to implement the channel whenever such a protocol exists in any finite number of rounds. Perhaps surprisingly, the computational expense for analyzing LOCC channels is not much greater than that for LOCC measurements. We apply the method to several examples, two of which provide numerical evidence that the set of quantum channels that are not LOCC is not closed and that there exist channels that can be implemented by LOCC either in one round or in three rounds that are on the boundary of the set of all LOCC channels. Although every LOCC protocol must implement a separable quantum channel, it is a very difficult task to determine whether or not a given channel is separable. Fortunately, prior knowledge that the channel is separable is not required for application of our method.

  1. Development and testing of an implementation strategy for a complex housing intervention: protocol for a mixed methods study.

    PubMed

    Watson, Dennis P; Young, Jeani; Ahonen, Emily; Xu, Huiping; Henderson, Macey; Shuman, Valery; Tolliver, Randi

    2014-10-17

    There is currently a lack of scientifically designed and tested implementation strategies. Such strategies are particularly important for highly complex interventions that require coordination between multiple parts to be successful. This paper presents a protocol for the development and testing of an implementation strategy for a complex intervention known as the Housing First model (HFM). Housing First is an evidence-based practice for chronically homeless individuals demonstrated to significantly improve a number of outcomes. Drawing on practices demonstrated to be useful in implementation and e-learning theory, our team is currently adapting a face-to-face implementation strategy so that it can be delivered over a distance. Research activities will be divided between Chicago and Central Indiana, two areas with significantly different barriers to HFM implementation. Ten housing providers (five from Chicago and five from Indiana) will be recruited to conduct an alpha test of each of four e-learning modules as they are developed. Providers will be requested to keep a detailed log of their experience completing the modules and participate in one of two focus groups. After refining the modules based on alpha test results, we will test the strategy among a sample of four housing organizations (two from Chicago and two from Indiana). We will collect and analyze both qualitative and quantitative data from administration and staff. Measures of interest include causal factors affecting implementation, training outcomes, and implementation outcomes. This project is an important first step in the development of an evidence-based implementation strategy to increase scalability and impact of the HFM. The project also has strong potential to increase limited scientific knowledge regarding implementation strategies in general.

  2. Intercept-Resend-Measure Attack Towards Quantum Private Comparison Protocol Using Genuine Four-Particle Entangled States and its Improvement

    NASA Astrophysics Data System (ADS)

    Pan, Hong-Ming

    2018-03-01

    Recently, Jia et al. proposed the quantum private comparison protocol with the genuine four-particle entangled states (Jia et al., Int. J. Theor. Phys. 51(4), 1187-1194 (2012)). Jia et al. claimed that in this protocol, TP cannot obtain Alice and Bob's secrets and only knows their comparison result. However, in this paper, we demonstrate that if TP is a genuine semi-honest third party, he can totally obtain Alice and Bob's secrets by launching a particular intercept-resend-measure attack. After suggesting the intercept-resend-measure attack strategy from TP first, we put forward one corresponding improvement to prevent this attack.

  3. The impacts of electricity dispatch protocols on the emission reductions due to wind power and carbon tax.

    PubMed

    Yu, Yang; Rajagopal, Ram

    2015-02-17

    Two dispatch protocols have been adopted by electricity markets to deal with the uncertainty of wind power but the effects of the selection between the dispatch protocols have not been comprehensively analyzed. We establish a framework to compare the impacts of adopting different dispatch protocols on the efficacy of using wind power and implementing a carbon tax to reduce emissions. We suggest that a market has high potential to achieve greater emission reduction by adopting the stochastic dispatch protocol instead of the static protocol when the wind energy in the market is highly uncertain or the market has enough adjustable generators, such as gas-fired combustion generators. Furthermore, the carbon-tax policy is more cost-efficient for reducing CO2 emission when the market operates according to the stochastic protocol rather than the static protocol. An empirical study, which is calibrated according to the data from the Electric Reliability Council of Texas market, confirms that using wind energy in the Texas market results in a 12% CO2 emission reduction when the market uses the stochastic dispatch protocol instead of the 8% emission reduction associated with the static protocol. In addition, if a 6$/ton carbon tax is implemented in the Texas market operated according to the stochastic protocol, the CO2 emission is similar to the emission level from the same market with a 16$/ton carbon tax operated according to the static protocol. Correspondingly, the 16$/ton carbon tax associated with the static protocol costs 42.6% more than the 6$/ton carbon tax associated with the stochastic protocol.

  4. 76 FR 82180 - International Fisheries; Western and Central Pacific Fisheries for Highly Migratory Species...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-30

    ... international obligations of the United States as a Contracting Party to the Convention, NMFS must implement... necessary for the United States to satisfy its international obligations under the Convention on the... (Convention), to which it is a Contracting Party. DATES: Effective on December 30, 2011, comments must be...

  5. 22 CFR 521.17 - Rights of parties.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Rights of parties. 521.17 Section 521.17 Foreign Relations BROADCASTING BOARD OF GOVERNORS IMPLEMENTATION OF THE PROGRAM FRAUD CIVIL REMEDIES ACT § 521.17... discovery; (d) Agree to stipulations of fact or law, which shall be made part of the record; (e) Present...

  6. 38 CFR 42.36 - Post-hearing briefs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) STANDARDS IMPLEMENTING THE PROGRAM FRAUD CIVIL REMEDIES ACT § 42.36 Post-hearing briefs. The ALJ may require the parties to file post-hearing briefs. In any event, any party may file a post-hearing brief. The... 38 Pensions, Bonuses, and Veterans' Relief 2 2011-07-01 2011-07-01 false Post-hearing briefs. 42...

  7. 38 CFR 42.36 - Post-hearing briefs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) STANDARDS IMPLEMENTING THE PROGRAM FRAUD CIVIL REMEDIES ACT § 42.36 Post-hearing briefs. The ALJ may require the parties to file post-hearing briefs. In any event, any party may file a post-hearing brief. The... 38 Pensions, Bonuses, and Veterans' Relief 2 2014-07-01 2014-07-01 false Post-hearing briefs. 42...

  8. 38 CFR 42.36 - Post-hearing briefs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) STANDARDS IMPLEMENTING THE PROGRAM FRAUD CIVIL REMEDIES ACT § 42.36 Post-hearing briefs. The ALJ may require the parties to file post-hearing briefs. In any event, any party may file a post-hearing brief. The... 38 Pensions, Bonuses, and Veterans' Relief 2 2012-07-01 2012-07-01 false Post-hearing briefs. 42...

  9. 38 CFR 42.36 - Post-hearing briefs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) STANDARDS IMPLEMENTING THE PROGRAM FRAUD CIVIL REMEDIES ACT § 42.36 Post-hearing briefs. The ALJ may require the parties to file post-hearing briefs. In any event, any party may file a post-hearing brief. The... 38 Pensions, Bonuses, and Veterans' Relief 2 2013-07-01 2013-07-01 false Post-hearing briefs. 42...

  10. 38 CFR 42.36 - Post-hearing briefs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) STANDARDS IMPLEMENTING THE PROGRAM FRAUD CIVIL REMEDIES ACT § 42.36 Post-hearing briefs. The ALJ may require the parties to file post-hearing briefs. In any event, any party may file a post-hearing brief. The... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Post-hearing briefs. 42...

  11. Environmental effects of ozone depletion and its interactions with climate change: progress report, 2015

    EPA Science Inventory

    The Environmental Effects Assessment Panel (EEAP) is one of three Panels that regularly informs the Parties (countries) to the Montreal Protocol on the effects of ozone depletion and the consequences of climate change interactions with respect to human health, animals, plants, bi...

  12. Planning meals: Problem-solving on a real data-base

    ERIC Educational Resources Information Center

    Byrne, Richard

    1977-01-01

    Planning the menu for a dinner party, which involves problem-solving with a large body of knowledge, is used to study the daily operation of human memory. Verbal protocol analysis, a technique devised to investigate formal problem-solving, is examined theoretically and adapted for analysis of this task. (Author/MV)

  13. Bringing social standards into project evaluation under dynamic uncertainty.

    PubMed

    Knudsen, Odin K; Scandizzo, Pasquale L

    2005-04-01

    Society often sets social standards that define thresholds of damage to society or the environment above which compensation must be paid to the state or other parties. In this article, we analyze the interdependence between the use of social standards and investment evaluation under dynamic uncertainty where a negative externality above a threshold established by society requires an assessment and payment of damages. Under uncertainty, the party considering implementing a project or new technology must not only assess when the project is economically efficient to implement but when to abandon a project that could potentially exceed the social standard. Using real-option theory and simple models, we demonstrate how such a social standard can be integrated into cost-benefit analysis through the use of a development option and a liability option coupled with a damage function. Uncertainty, in fact, implies that both parties interpret the social standard as a target for safety rather than an inflexible barrier that cannot be overcome. The larger is the uncertainty, in fact, the greater will be the tolerance for damages in excess of the social standard from both parties.

  14. Probabilistic Teleportation of an Arbitrary Two-Qubit State via Positive Operator-Valued Measurement with Multi Parties

    NASA Astrophysics Data System (ADS)

    Shi, Lei; Wei, Jia-Hua; Li, Yun-Xia; Ma, Li-Hua; Xue, Yang; Luo, Jun-Wen

    2017-04-01

    We propose a novel scheme to probabilistically transmit an arbitrary unknown two-qubit quantum state via Positive Operator-Valued Measurement with the help of two partially entangled states. In this scheme, the teleportation with two senders and two receives can be realized when the information of non-maximally entangled states is only available for the senders. Furthermore, the concrete implementation processes of this proposal are presented, meanwhile the classical communication cost and the successful probability of our scheme are calculated. Supported by the National Natural Science Foundation of China under Grant Nos. 60974037, 61134008, 11074307, and 61273202

  15. Improvement of two-way continuous-variable quantum key distribution with virtual photon subtraction

    NASA Astrophysics Data System (ADS)

    Zhao, Yijia; Zhang, Yichen; Li, Zhengyu; Yu, Song; Guo, Hong

    2017-08-01

    We propose a method to improve the performance of two-way continuous-variable quantum key distribution protocol by virtual photon subtraction. The virtual photon subtraction implemented via non-Gaussian post-selection not only enhances the entanglement of two-mode squeezed vacuum state but also has advantages in simplifying physical operation and promoting efficiency. In two-way protocol, virtual photon subtraction could be applied on two sources independently. Numerical simulations show that the optimal performance of renovated two-way protocol is obtained with photon subtraction only used by Alice. The transmission distance and tolerable excess noise are improved by using the virtual photon subtraction with appropriate parameters. Moreover, the tolerable excess noise maintains a high value with the increase in distance so that the robustness of two-way continuous-variable quantum key distribution system is significantly improved, especially at long transmission distance.

  16. Dual watermarking scheme for secure buyer-seller watermarking protocol

    NASA Astrophysics Data System (ADS)

    Mehra, Neelesh; Shandilya, Madhu

    2012-04-01

    A buyer-seller watermarking protocol utilize watermarking along with cryptography for copyright and copy protection for the seller and meanwhile it also preserve buyers rights for privacy. It enables a seller to successfully identify a malicious seller from a pirated copy, while preventing the seller from framing an innocent buyer and provide anonymity to buyer. Up to now many buyer-seller watermarking protocols have been proposed which utilize more and more cryptographic scheme to solve many common problems such as customer's rights, unbinding problem, buyer's anonymity problem and buyer's participation in the dispute resolution. But most of them are infeasible since the buyer may not have knowledge of cryptography. Another issue is the number of steps to complete the protocols are large, a buyer needs to interact with different parties many times in these protocols, which is very inconvenient for buyer. To overcome these drawbacks, in this paper we proposed dual watermarking scheme in encrypted domain. Since neither of watermark has been generated by buyer so a general layman buyer can use the protocol.

  17. Factors that impact on the use of mechanical ventilation weaning protocols in critically ill adults and children: a qualitative evidence-synthesis.

    PubMed

    Jordan, Joanne; Rose, Louise; Dainty, Katie N; Noyes, Jane; Blackwood, Bronagh

    2016-10-04

    Prolonged mechanical ventilation is associated with a longer intensive care unit (ICU) length of stay and higher mortality. Consequently, methods to improve ventilator weaning processes have been sought. Two recent Cochrane systematic reviews in ICU adult and paediatric populations concluded that protocols can be effective in reducing the duration of mechanical ventilation, but there was significant heterogeneity in study findings. Growing awareness of the benefits of understanding the contextual factors impacting on effectiveness has encouraged the integration of qualitative evidence syntheses with effectiveness reviews, which has delivered important insights into the reasons underpinning (differential) effectiveness of healthcare interventions. 1. To locate, appraise and synthesize qualitative evidence concerning the barriers and facilitators of the use of protocols for weaning critically-ill adults and children from mechanical ventilation;2. To integrate this synthesis with two Cochrane effectiveness reviews of protocolized weaning to help explain observed heterogeneity by identifying contextual factors that impact on the use of protocols for weaning critically-ill adults and children from mechanical ventilation;3. To use the integrated body of evidence to suggest the circumstances in which weaning protocols are most likely to be used. We used a range of search terms identified with the help of the SPICE (Setting, Perspective, Intervention, Comparison, Evaluation) mnemonic. Where available, we used appropriate methodological filters for specific databases. We searched the following databases: Ovid MEDLINE, Embase, OVID, PsycINFO, CINAHL Plus, EBSCOHost, Web of Science Core Collection, ASSIA, IBSS, Sociological Abstracts, ProQuest and LILACS on the 26th February 2015. In addition, we searched: the grey literature; the websites of professional associations for relevant publications; and the reference lists of all publications reviewed. We also contacted authors of the trials included in the effectiveness reviews as well as of studies (potentially) included in the qualitative synthesis, conducted citation searches of the publications reporting these studies, and contacted content experts.We reran the search on 3rd July 2016 and found three studies, which are awaiting classification. We included qualitative studies that described: the circumstances in which protocols are designed, implemented or used, or both, and the views and experiences of healthcare professionals either involved in the design, implementation or use of weaning protocols or involved in the weaning of critically-ill adults and children from mechanical ventilation not using protocols. We included studies that: reflected on any aspect of the use of protocols, explored contextual factors relevant to the development, implementation or use of weaning protocols, and reported contextual phenomena and outcomes identified as relevant to the effectiveness of protocolized weaning from mechanical ventilation. At each stage, two review authors undertook designated tasks, with the results shared amongst the wider team for discussion and final development. We independently reviewed all retrieved titles, abstracts and full papers for inclusion, and independently extracted selected data from included studies. We used the findings of the included studies to develop a new set of analytic themes focused on the barriers and facilitators to the use of protocols, and further refined them to produce a set of summary statements. We used the Confidence in the Evidence from Reviews of Qualitative Research (CERQual) framework to arrive at a final assessment of the overall confidence of the evidence used in the synthesis. We included all studies but undertook two sensitivity analyses to determine how the removal of certain bodies of evidence impacted on the content and confidence of the synthesis. We deployed a logic model to integrate the findings of the qualitative evidence synthesis with those of the Cochrane effectiveness reviews. We included 11 studies in our synthesis, involving 267 participants (one study did not report the number of participants). Five more studies are awaiting classification and will be dealt with when we update the review.The quality of the evidence was mixed; of the 35 summary statements, we assessed 17 as 'low', 13 as 'moderate' and five as 'high' confidence. Our synthesis produced nine analytical themes, which report potential barriers and facilitators to the use of protocols. The themes are: the need for continual staff training and development; clinical experience as this promotes felt and perceived competence and confidence to wean; the vulnerability of weaning to disparate interprofessional working; an understanding of protocols as militating against a necessary proactivity in clinical practice; perceived nursing scope of practice and professional risk; ICU structure and processes of care; the ability of protocols to act as a prompt for shared care and consistency in weaning practice; maximizing the use of protocols through visibility and ease of implementation; and the ability of protocols to act as a framework for communication with parents. There is a clear need for weaning protocols to take account of the social and cultural environment in which they are to be implemented. Irrespective of its inherent strengths, a protocol will not be used if it does not accommodate these complexities. In terms of protocol development, comprehensive interprofessional input will help to ensure broad-based understanding and a sense of 'ownership'. In terms of implementation, all relevant ICU staff will benefit from general weaning as well as protocol-specific training; not only will this help secure a relevant clinical knowledge base and operational understanding, but will also demonstrate to others that this knowledge and understanding is in place. In order to maximize relevance and acceptability, protocols should be designed with the patient profile and requirements of the target ICU in mind. Predictably, an under-resourced ICU will impact adversely on protocol implementation, as staff will prioritize management of acutely deteriorating and critically-ill patients.

  18. SPP: A data base processor data communications protocol

    NASA Technical Reports Server (NTRS)

    Fishwick, P. A.

    1983-01-01

    The design and implementation of a data communications protocol for the Intel Data Base Processor (DBP) is defined. The protocol is termed SPP (Service Port Protocol) since it enables data transfer between the host computer and the DBP service port. The protocol implementation is extensible in that it is explicitly layered and the protocol functionality is hierarchically organized. Extensive trace and performance capabilities have been supplied with the protocol software to permit optional efficient monitoring of the data transfer between the host and the Intel data base processor. Machine independence was considered to be an important attribute during the design and implementation of SPP. The protocol source is fully commented and is included in Appendix A of this report.

  19. [U.S. renewable fuel standard implementation mechanism and market tracking].

    PubMed

    Kang, Liping; Earley, Robert; An, Feng; Zhang, Yu

    2013-03-01

    U.S. Renewable Fuel Standard (RFS) is a mandatory policy for promoting the utilization of biofuels in road transpiration sector in order to reduce the country's dependency on foreign oil and greenhouse gas emissions. U.S. Environmental Protection Agency (EPA) defines the proportion of renewable fuels according to RFS annual target, and requests obligated parties such like fossil fuel refiner, blenders and importer in the U.S. to complete Renewable Volume Obligation (RVO) every year. Obligated parties prove they have achieved their RVO through a renewable fuels certification system, which generates Renewable Identification Numbers (RINs) for every gallon of qualified renewable fuels produced or imported into U.S., RINs is a key for tracking renewable fuel consumption, which in turn is a key for implementing the RFS in the U.S., separated RINs can be freely traded in market and obligated parties could fulfill their RVO through buying RINs from other stakeholders. This briefing paper highlights RFS policy implementing mechanism and marketing tracking, mainly describes importance of RINs, and the method for generating and tracking RINs by both government and fuels industry participants.

  20. Dynamic analysis methods for detecting anomalies in asynchronously interacting systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kumar, Akshat; Solis, John Hector; Matschke, Benjamin

    2014-01-01

    Detecting modifications to digital system designs, whether malicious or benign, is problematic due to the complexity of the systems being analyzed. Moreover, static analysis techniques and tools can only be used during the initial design and implementation phases to verify safety and liveness properties. It is computationally intractable to guarantee that any previously verified properties still hold after a system, or even a single component, has been produced by a third-party manufacturer. In this paper we explore new approaches for creating a robust system design by investigating highly-structured computational models that simplify verification and analysis. Our approach avoids the needmore » to fully reconstruct the implemented system by incorporating a small verification component that dynamically detects for deviations from the design specification at run-time. The first approach encodes information extracted from the original system design algebraically into a verification component. During run-time this component randomly queries the implementation for trace information and verifies that no design-level properties have been violated. If any deviation is detected then a pre-specified fail-safe or notification behavior is triggered. Our second approach utilizes a partitioning methodology to view liveness and safety properties as a distributed decision task and the implementation as a proposed protocol that solves this task. Thus the problem of verifying safety and liveness properties is translated to that of verifying that the implementation solves the associated decision task. We develop upon results from distributed systems and algebraic topology to construct a learning mechanism for verifying safety and liveness properties from samples of run-time executions.« less

  1. Implementation of an Emergency Department Sepsis Bundle and System Redesign: A Process Improvement Initiative.

    PubMed

    McColl, Tamara; Gatien, Mathieu; Calder, Lisa; Yadav, Krishan; Tam, Ryan; Ong, Melody; Taljaard, Monica; Stiell, Ian

    2017-03-01

    In 2008-2009, the Canadian Institute for Health Information reported over 30,000 cases of sepsis hospitalizations in Canada, an increase of almost 4,000 from 2005. Mortality rates from severe sepsis and septic shock continue to remain greater than 30% in Canada and are significantly higher than other critical conditions treated in the emergency department (ED). Our group formed a multidisciplinary sepsis committee, conducted an ED process of care analysis, and developed a quality improvement protocol. The objective of this study was to evaluate the effects of this sepsis management bundle on patient mortality. This before and after study was conducted in two large Canadian tertiary care EDs and included adult patients with suspected severe infection that met at least two systemic inflammatory response syndrome (SIRS) criteria. We studied the implementation of a sepsis bundle including triage flagging, RN medical directive, education campaign, and a modified sepsis protocol. The primary outcomes were 30-day all-cause mortality and sepsis protocol use. We included a total of 167 and 185 patients in the pre- and post-intervention analysis, respectively. Compared to the pre-intervention group, mortality was significantly lower in the post-intervention group (30.7% versus 17.3%; absolute difference, 13.4%; 95% CI 9.8-17.0; p=0.006). There was also a higher rate of sepsis protocol use in the post-intervention group (20.3% versus 80.5%, absolute difference 60.2%; 95% CI 55.1-65.3; p<0.001). Additionally, we found shorter time-intervals from triage to MD assessment, fluid resuscitation, and antibiotic administration as well as lower rates of vasopressor requirements and ICU admission. Interpretation The implementation of our multidisciplinary ED sepsis bundle, including improved early identification and protocolized medical care, was associated with improved time to achieve key therapeutic interventions and a reduction in 30-day mortality. Similar low-cost initiatives could be implemented in other EDs to potentially improve outcomes for this high-risk group of patients.

  2. Symmetrically private information retrieval based on blind quantum computing

    NASA Astrophysics Data System (ADS)

    Sun, Zhiwei; Yu, Jianping; Wang, Ping; Xu, Lingling

    2015-05-01

    Universal blind quantum computation (UBQC) is a new secure quantum computing protocol which allows a user Alice who does not have any sophisticated quantum technology to delegate her computing to a server Bob without leaking any privacy. Using the features of UBQC, we propose a protocol to achieve symmetrically private information retrieval, which allows a quantum limited Alice to query an item from Bob with a fully fledged quantum computer; meanwhile, the privacy of both parties is preserved. The security of our protocol is based on the assumption that malicious Alice has no quantum computer, which avoids the impossibility proof of Lo. For the honest Alice, she is almost classical and only requires minimal quantum resources to carry out the proposed protocol. Therefore, she does not need any expensive laboratory which can maintain the coherence of complicated quantum experimental setups.

  3. The Interplanetary Overlay Networking Protocol Accelerator

    NASA Technical Reports Server (NTRS)

    Pang, Jackson; Torgerson, Jordan L.; Clare, Loren P.

    2008-01-01

    A document describes the Interplanetary Overlay Networking Protocol Accelerator (IONAC) an electronic apparatus, now under development, for relaying data at high rates in spacecraft and interplanetary radio-communication systems utilizing a delay-tolerant networking protocol. The protocol includes provisions for transmission and reception of data in bundles (essentially, messages), transfer of custody of a bundle to a recipient relay station at each step of a relay, and return receipts. Because of limitations on energy resources available for such relays, data rates attainable in a conventional software implementation of the protocol are lower than those needed, at any given reasonable energy-consumption rate. Therefore, a main goal in developing the IONAC is to reduce the energy consumption by an order of magnitude and the data-throughput capability by two orders of magnitude. The IONAC prototype is a field-programmable gate array that serves as a reconfigurable hybrid (hardware/ firmware) system for implementation of the protocol. The prototype can decode 108,000 bundles per second and encode 100,000 bundles per second. It includes a bundle-cache static randomaccess memory that enables maintenance of a throughput of 2.7Gb/s, and an Ethernet convergence layer that supports a duplex throughput of 1Gb/s.

  4. Study of consensus-based time synchronization in wireless sensor networks.

    PubMed

    He, Jianping; Li, Hao; Chen, Jiming; Cheng, Peng

    2014-03-01

    Recently, various consensus-based protocols have been developed for time synchronization in wireless sensor networks. However, due to the uncertainties lying in both the hardware fabrication and network communication processes, it is not clear how most of the protocols will perform in real implementations. In order to reduce such gap, this paper investigates whether and how the typical consensus-based time synchronization protocols can tolerate the uncertainties in practical sensor networks through extensive testbed experiments. For two typical protocols, i.e., Average Time Synchronization (ATS) and Maximum Time Synchronization (MTS), we first analyze how the time synchronization accuracy will be affected by various uncertainties in the system. Then, we implement both protocols on our sensor network testbed consisted of Micaz nodes, and investigate the time synchronization performance and robustness under various network settings. Noticing that the synchronized clocks under MTS may be slightly faster than the desirable clock, by adopting both maximum consensus and minimum consensus, we propose a modified protocol, MMTS, which is able to drive the synchronized clocks closer to the desirable clock while maintaining the convergence rate and synchronization accuracy of MTS. © 2013 ISA. Published by ISA. All rights reserved.

  5. Quantum fingerprinting with coherent states and a constant mean number of photons

    NASA Astrophysics Data System (ADS)

    Arrazola, Juan Miguel; Lütkenhaus, Norbert

    2014-06-01

    We present a protocol for quantum fingerprinting that is ready to be implemented with current technology and is robust to experimental errors. The basis of our scheme is an implementation of the signal states in terms of a coherent state in a superposition of time-bin modes. Experimentally, this requires only the ability to prepare coherent states of low amplitude and to interfere them in a balanced beam splitter. The states used in the protocol are arbitrarily close in trace distance to states of O (log2n) qubits, thus exhibiting an exponential separation in abstract communication complexity compared to the classical case. The protocol uses a number of optical modes that is proportional to the size n of the input bit strings but a total mean photon number that is constant and independent of n. Given the expended resources, our protocol achieves a task that is provably impossible using classical communication only. In fact, even in the presence of realistic experimental errors and loss, we show that there exist a large range of input sizes for which our quantum protocol transmits an amount of information that can be more than two orders of magnitude smaller than a classical fingerprinting protocol.

  6. Evaluation of the Effectiveness of Two Morphine Protocols to Treat Neonatal Abstinence Syndrome in a Level II Nursery in a Community Hospital.

    PubMed

    DeAtley, Heather N; Burton, Amanda; Fraley, Michelle DeLuca; Haltom, Joan

    2017-07-01

    The authors sought to evaluate the impact on length of hospital stay and treatment duration of morphine after implementation of a change in the institutional protocol for managing neonatal abstinence syndrome (NAS) in an effort to improve patient outcomes. A single-center, retrospective chart review was conducted at a Level II nursery in a community hospital in Kentucky. Fifty-nine neonates born between January 1, 2014, and December 31, 2015, who were diagnosed with NAS and received morphine for treatment were included. The protocol 1 group consisted of 33 neonates who received an initial dose of morphine 0.04 mg/kg/dose administered orally every 4 hours (January 1-December 31, 2014), and the protocol 2 group consisted of 26 neonates who received an initial dose of morphine 0.06 mg/kg/dose administered orally every 3 hours (January 1-November 30, 2015), after a change in the protocol for managing NAS was implemented on January 1, 2015. Data were reviewed and compared between the two protocol groups to determine the impact that the dosage change had on length of hospital stay and morphine treatment duration. The average length of stay decreased by 7 days in the protocol 2 group compared with the protocol 1 group (21 vs 28.65 days). The average duration of treatment decreased by 7 days in the protocol 2 group compared with the protocol 1 group (18.3 vs 25.4 days). These differences between groups were not statistically significant, however, because the population size was not large enough to achieve adequate power. These results indicate that protocol 2 displayed the potential to decrease length of stay and duration of treatment compared with protocol 1 at this facility; however, balancing higher starting doses with the risk of oversedation will continue to challenge the health care team. Concern for oversedation when using the higher starting dose in protocol 2 has prompted further research (e.g., protocol 3, initial morphine 0.05 mg/kg/dose every 3 hrs). Continued research is also necessary with larger patient populations to enable generalizability to other institutions. © 2017 Pharmacotherapy Publications, Inc.

  7. 41 CFR 105-70.036 - Post-hearing briefs.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Administration 70-IMPLEMENTATION OF THE PROGRAM FRAUD CIVIL REMEDIES ACT OF 1986 § 105-70.036 Post-hearing briefs. The ALJ may require the parties to file post-hearing briefs. In any event, any party may file a post... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Post-hearing briefs. 105...

  8. 41 CFR 105-70.036 - Post-hearing briefs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Administration 70-IMPLEMENTATION OF THE PROGRAM FRAUD CIVIL REMEDIES ACT OF 1986 § 105-70.036 Post-hearing briefs. The ALJ may require the parties to file post-hearing briefs. In any event, any party may file a post... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Post-hearing briefs. 105...

  9. 41 CFR 105-70.036 - Post-hearing briefs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Administration 70-IMPLEMENTATION OF THE PROGRAM FRAUD CIVIL REMEDIES ACT OF 1986 § 105-70.036 Post-hearing briefs. The ALJ may require the parties to file post-hearing briefs. In any event, any party may file a post... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Post-hearing briefs. 105...

  10. 41 CFR 105-70.036 - Post-hearing briefs.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Administration 70-IMPLEMENTATION OF THE PROGRAM FRAUD CIVIL REMEDIES ACT OF 1986 § 105-70.036 Post-hearing briefs. The ALJ may require the parties to file post-hearing briefs. In any event, any party may file a post... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Post-hearing briefs. 105...

  11. 77 FR 57035 - Notice of Commission's Implementation of Procedure of Serving Parties in an Electronic Format

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-17

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 1 [GC Docket No. 10-44; DA 12-1401] Notice of... . SUPPLEMENTARY INFORMATION: This is a synopsis of the Commission's Public Notice, document DA 12-1401, released... Procedure of Serving Parties in an Electronic Format. The full text of DA [[Page 57036

  12. 77 FR 42149 - Changes To Implement the Preissuance Submissions by Third Parties Provision of the Leahy-Smith...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-17

    ...; (4) an English language translation of any non-English language item listed; (5) a statement by the...-party submission was found to be non- compliant. Section 1.290(d)(4) requires an English language translation of any non-English language item identified in the document list. A translation submitted pursuant...

  13. Universal Barenco quantum gates via a tunable noncollinear interaction

    NASA Astrophysics Data System (ADS)

    Shi, Xiao-Feng

    2018-03-01

    The Barenco gate (B ) is a type of two-qubit quantum gate based on which alone universal quantum computation can be achieved. Each B is characterized by three angles (α , θ , and ϕ ), though it works in a two-qubit Hilbert space. Here we design B via a noncollinear interaction V | r1r2>< r1r3|+H .c . , where | ri> is a state that can be excited from a qubit state and V is adjustable. We present two protocols for B . The first (second) protocol consists of two (six) pulses and one (two) wait period(s), where the former causes rotations between qubit states and excited states, and the latter induces gate transformation via the noncollinear interaction. In the first protocol, the variable ϕ can be tuned by varying the phases of external controls, and the other two variables α and θ , tunable via adjustment of the wait duration, have a linear dependence on each other. Meanwhile, the first protocol can give rise to cnot and controlled-y gates. In the second protocol, α ,θ , and ϕ can be varied by changing the interaction amplitudes and wait durations, and the latter two are dependent on α nonlinearly. Both protocols can also lead to another universal gate when {α ,ϕ }={1 /4 ,1 /2 }π with appropriate parameters. Implementation of these universal gates is analyzed based on the van der Waals interaction of neutral Rydberg atoms.

  14. Analysis of misoprostol and chlorhexidine policy gains in Pakistan: the advocacy experience of Mercy Corps Pakistan.

    PubMed

    Sarwar, Zahida; Cutherell, Andrea; Noor, Arif; Naureen, Farah; Norman, Jennifer

    2015-11-25

    While Pakistan has made progress toward achieving Millennium Development Goal 5 for maternal health, it is unlikely to achieve the target; further, it is also not on track for Millennium Development Goal 4 regarding child health. Two low-cost, temperature stable and life-saving drugs, misoprostol and chlorhexidine, can respectively avert maternal and newborn deaths, and are particularly pertinent for poor and marginalized areas which bear the brunt of maternal and newborn deaths in Pakistan. In response, Mercy Corps led focused advocacy efforts to promote changes in policies, protocols, and regulatory environments for misoprostol (2012-2014) and for chlorhexidine (2014). These short-duration advocacy projects facilitated significant policy gains, such as inclusion of misoprostol and chlorhexidine into province-specific essential drug lists, development and endorsement of clinical protocols for the two drugs by provincial health departments, inclusion of misoprostol into pre-service training curriculum for several health cadres, and application for registration of chlorhexidine (at the concentration required for newborn care) by two pharmaceutical companies. These results were achieved by a consultative and evidence-based process which generated feedback from community members, program implementers, and policymakers, and ultimately put the government in the driver's seat to facilitate change. Community Action Dialogue forums were linked with provincial-level Technical Working Groups and Provincial Steering Committees, who passed on endorsed recommendations to the Health Secretary. The key factors which facilitated change were the identification of champions within the provincial health departments, prioritization of relationship building and follow-up, focus on concrete advocacy aims rather than broad objectives, and the use of multi-stakeholder forums to secure an enabling environment for the policy changes to take root. While these advocacy initiatives resulted in significant policy changes in Pakistan's devolved health system, to ensure these policy changes have an impact on health outcomes, Pakistan should focus on the scale-up of appropriate use of chlorhexidine and misoprostol. Further, future policy initiatives in Pakistan should make use of similar multi-stakeholder policy forums, while ensuring a third party to facilitate the process so that civil society and community voices are not lost in the policy development discussion.

  15. Impact of a pharmacist-driven warfarin management protocol on achieving therapeutic International Normalized Ratios.

    PubMed

    Downing, Amanda; Mortimer, Molly; Hiers, Jill

    2016-03-01

    Warfarin is a high alert medication and a challenge to dose and monitor. Pharmacist-driven warfarin management has been shown to decrease the time international normalized ratio (INR) is out of range, which may reduce undesired outcomes. The purpose of this study is to assess the effect of the implementation of a pharmacist-driven warfarin management protocol on the achievement of therapeutic INRs. A warfarin management protocol was developed using evidence based literature and similar protocols from other institutions. Pharmacists utilized the protocol to provide patient specific warfarin dosing upon provider referral. To evaluate the protocol's impact, a retrospective chart review pre- and post-implementation was completed for admitted patients receiving warfarin. Three hundred twenty-seven charts were reviewed for pre- and post-implementation data. INRs within therapeutic range increased from 27.8% before protocol implementation to 38.5% after implementation. There was also a reduction in subtherapeutic INRs (55.3% pre to 39% post) and supratherapeutic INRs 5 or above (3.7% pre to 2.6% post). Supratherapeutic INRs between 3 and 5 did increase from 13.2% before protocol implementation to 19.9% in the pharmacist managed group. In addition to reducing the time to achievement of therapeutic INRs by 0.5 days, implementation of the protocol resulted in an increased the number of patients with at least one therapeutic INR during admission (35% pre to 40% post). The implementation of a pharmacist-driven warfarin dosing protocol increased therapeutic INRs, and decreased the time to therapeutic range, as well as the proportion of subtherapeutic INRs and supratherapeutic INRs 5 or greater. Additional benefits of the protocol include documentation of Joint Commission National Patient Safety Goal compliance, promotion of interdisciplinary collaboration and increased continuity of care. Copyright © 2016 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

  16. Evolution equation for quantum entanglement

    NASA Astrophysics Data System (ADS)

    Konrad, Thomas; de Melo, Fernando; Tiersch, Markus; Kasztelan, Christian; Aragão, Adriano; Buchleitner, Andreas

    2008-02-01

    Quantum information technology largely relies on a precious and fragile resource, quantum entanglement, a highly non-trivial manifestation of the coherent superposition of states of composite quantum systems. However, our knowledge of the time evolution of this resource under realistic conditions-that is, when corrupted by environment-induced decoherence-is so far limited, and general statements on entanglement dynamics in open systems are scarce. Here we prove a simple and general factorization law for quantum systems shared by two parties, which describes the time evolution of entanglement on passage of either component through an arbitrary noisy channel. The robustness of entanglement-based quantum information processing protocols is thus easily and fully characterized by a single quantity.

  17. Experimentally superposing two pure states with partial prior knowledge

    NASA Astrophysics Data System (ADS)

    Li, Keren; Long, Guofei; Katiyar, Hemant; Xin, Tao; Feng, Guanru; Lu, Dawei; Laflamme, Raymond

    2017-02-01

    Superposition, arguably the most fundamental property of quantum mechanics, lies at the heart of quantum information science. However, how to create the superposition of any two unknown pure states remains as a daunting challenge. Recently, it was proved that such a quantum protocol does not exist if the two input states are completely unknown, whereas a probabilistic protocol is still available with some prior knowledge about the input states [M. Oszmaniec et al., Phys. Rev. Lett. 116, 110403 (2016), 10.1103/PhysRevLett.116.110403]. The knowledge is that both of the two input states have nonzero overlaps with some given referential state. In this work, we experimentally realize the probabilistic protocol of superposing two pure states in a three-qubit nuclear magnetic resonance system. We demonstrate the feasibility of the protocol by preparing a families of input states, and the average fidelity between the prepared state and expected superposition state is over 99%. Moreover, we experimentally illustrate the limitation of the protocol that it is likely to fail or yields very low fidelity, if the nonzero overlaps are approaching zero. Our experimental implementation can be extended to more complex situations and other quantum systems.

  18. Optimality of Gaussian attacks in continuous-variable quantum cryptography.

    PubMed

    Navascués, Miguel; Grosshans, Frédéric; Acín, Antonio

    2006-11-10

    We analyze the asymptotic security of the family of Gaussian modulated quantum key distribution protocols for continuous-variables systems. We prove that the Gaussian unitary attack is optimal for all the considered bounds on the key rate when the first and second momenta of the canonical variables involved are known by the honest parties.

  19. 75 FR 43597 - Self-Regulatory Organizations; NASDAQ OMX PHLX, Inc.; Notice of Filing of Proposed Rule Change...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-26

    ...-party connectivity providers, including a range of extranets and service bureaus. All of the communications protocols will be publicly available to allow Participants and services bureaus to develop their... agreements with PHLX (including the NASDAQ OMX U.S. Services Agreement \\8\\); maintain membership in, or...

  20. Purified discord and multipartite entanglement

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brown, Eric G.; Webster, Eric J.; Martín-Martínez, Eduardo, E-mail: emmfis@gmail.com

    2013-10-15

    We study bipartite quantum discord as a manifestation of a multipartite entanglement structure in the tripartite purified system. In particular, we find that bipartite quantum discord requires the presence of both bipartite and tripartite entanglement in the purification. This allows one to understand the asymmetry of quantum discord, D(A,B)≠D(B,A) in terms of entanglement monogamy. As instructive special cases, we study discord for qubits and Gaussian states in detail. As a result of this we shed new light on a counterintuitive property of Gaussian states: the presence of classical correlations necessarily requires the presence of quantum correlations. Finally, our results alsomore » shed new light on a protocol for remote activation of entanglement by a third party. -- Highlights: •Bipartite quantum discord as a manifestation of multipartite entanglement. •Relevance of quantum discord as a utilizable resource for quantum info. tasks. •Quantum discord manifests itself in entanglement in the purified state. •Relation between asymmetry of discord and entanglement monogamy. •Protocol for remote activation of entanglement by a third party.« less

Top