An Inexpensive Device for Teaching Public Key Encryption
ERIC Educational Resources Information Center
Pendegraft, Norman
2009-01-01
An inexpensive device to assist in teaching the main ideas of Public Key encryption and its use in class to illustrate the operation of public key encryption is described. It illustrates that there are two keys, and is particularly useful for illustrating that privacy is achieved by using the public key. Initial data from in class use seem to…
Public-key encryption and authentication of quantum information
NASA Astrophysics Data System (ADS)
Liang, Min; Yang, Li
2012-09-01
Public-key cryptosystems for quantum messages are considered from two aspects: public-key encryption and public-key authentication. Firstly, we propose a general construction of quantum public-key encryption scheme, and then construct an information-theoretic secure instance. Then, we propose a quantum public-key authentication scheme, which can protect the integrity of quantum messages. This scheme can both encrypt and authenticate quantum messages. It is information-theoretic secure with regard to encryption, and the success probability of tampering decreases exponentially with the security parameter with regard to authentication. Compared with classical public-key cryptosystems, one private-key in our schemes corresponds to an exponential number of public-keys, and every quantum public-key used by the sender is an unknown quantum state to the sender.
A complete classification of quantum public-key encryption protocols
NASA Astrophysics Data System (ADS)
Wu, Chenmiao; Yang, Li
2015-10-01
We present a classification of quantum public-key encryption protocols. There are six elements in quantum public-key encryption: plaintext, ciphertext, public-key, private-key, encryption algorithm and decryption algorithm. According to the property of each element which is either quantum or classical, the quantum public-key encryption protocols can be divided into 64 kinds. Among 64 kinds of protocols, 8 kinds have already been constructed, 52 kinds can be proved to be impossible to construct and the remaining 4 kinds have not been presented effectively yet. This indicates that the research on quantum public-key encryption protocol should be focus on the existed kinds and the unproposed kinds.
Deducing trapdoor primitives in public key encryption schemes
NASA Astrophysics Data System (ADS)
Pandey, Chandra
2005-03-01
Semantic security of public key encryption schemes is often interchangeable with the art of building trapdoors. In the frame of reference of Random Oracle methodology, the "Key Privacy" and "Anonymity" has often been discussed. However to a certain degree the security of most public key encryption schemes is required to be analyzed with formal proofs using one-way functions. This paper evaluates the design of El Gamal and RSA based schemes and attempts to parallelize the trapdoor primitives used in the computation of the cipher text, thereby magnifying the decryption error δp in the above schemes.
Bit-oriented quantum public-key encryption based on quantum perfect encryption
NASA Astrophysics Data System (ADS)
Wu, Chenmiao; Yang, Li
2016-08-01
A bit-oriented quantum public-key encryption scheme is presented. We use Boolean functions as private-key and randomly changed pairs of quantum state and classical string as public-keys. Following the concept of quantum perfect encryption, we prepare the public-key with Hadamard transformation and Pauli transformation. The quantum part of public-keys is various with different classical strings. In contrast to the typical classical public-key scheme, one private-key in our scheme corresponds to an exponential number of public-keys. We investigate attack to the private-key and prove that the public-key is a totally mixed state. So the adversary cannot acquire any information about private-key from measurement of the public-key. Then, the attack to encryption is analyzed. Since the trace distance between two different ciphertexts is zero, the adversary cannot distinguish between the two ciphertext states and also obtains nothing about plaintext and private-key. Thus, we have the conclusion that the proposed scheme is information-theoretically secure under an attack of the private-key and encryption.
A public key encryption scheme based on idempotent semirings
NASA Astrophysics Data System (ADS)
Durcheva, Mariana; Rachev, Martin
2015-11-01
The problem of solving two sided linear equations in the idempotent semirings R¯m a x and R¯m i n has been proved to be reducible to the problem mean payoff game which is of the NP∩ coNP type. In the present paper, we use the mentioned security results and construct a new public key encryption scheme based on the hardness of the problem of solving two sided linear equations in the idempotent semirings.
Novel Public Key Encryption Technique Based on Multiple Chaotic Systems
NASA Astrophysics Data System (ADS)
Bose, Ranjan
2005-08-01
Public key encryption was first introduced by Diffie and Hellman in 1976. Since then, the Diffie-Hellman key exchange protocol has been used in developing public key systems such as Rivest-Shamir-Adleman and elliptic curve cryptography. Chaotic functions, so far, have been used for symmetric cryptography only. In this Letter we propose, for the first time, a methodology to use multiple chaotic systems and a set of linear functions for key exchange over an insecure channel. To the best of our knowledge, this is the first Letter that reports the use of chaotic systems for public key cryptography. We have shown that the security of the proposed algorithm grows as (NP)m, where N, P, and m are large numbers that can be chosen as the parameters of the cryptosystem.
Novel public key encryption technique based on multiple chaotic systems.
Bose, Ranjan
2005-08-26
Public key encryption was first introduced by Diffie and Hellman in 1976. Since then, the Diffie-Hellman key exchange protocol has been used in developing public key systems such as Rivest-Shamir-Adleman and elliptic curve cryptography. Chaotic functions, so far, have been used for symmetric cryptography only. In this Letter we propose, for the first time, a methodology to use multiple chaotic systems and a set of linear functions for key exchange over an insecure channel. To the best of our knowledge, this is the first Letter that reports the use of chaotic systems for public key cryptography. We have shown that the security of the proposed algorithm grows as (NP)(m), where N, P, and m are large numbers that can be chosen as the parameters of the cryptosystem.
NASA Astrophysics Data System (ADS)
Zhao, Tieyu; Ran, Qiwen; Yuan, Lin; Chi, Yingying; Ma, Jing
2015-09-01
In this paper, a novel image encryption system with fingerprint used as a secret key is proposed based on the phase retrieval algorithm and RSA public key algorithm. In the system, the encryption keys include the fingerprint and the public key of RSA algorithm, while the decryption keys are the fingerprint and the private key of RSA algorithm. If the users share the fingerprint, then the system will meet the basic agreement of asymmetric cryptography. The system is also applicable for the information authentication. The fingerprint as secret key is used in both the encryption and decryption processes so that the receiver can identify the authenticity of the ciphertext by using the fingerprint in decryption process. Finally, the simulation results show the validity of the encryption scheme and the high robustness against attacks based on the phase retrieval technique.
Deterministic quantum-public-key encryption: Forward search attack and randomization
NASA Astrophysics Data System (ADS)
Nikolopoulos, Georgios M.; Ioannou, Lawrence M.
2009-04-01
In the classical setting, public-key encryption requires randomness in order to be secure against a forward search attack, whereby an adversary compares the encryption of a guess of the secret message with the encryption of the actual secret message. We show that this is also true in the information-theoretic setting—where the public keys are quantum systems—by defining and giving an example of a forward search attack for any deterministic quantum-public-key bit-encryption scheme. However, unlike in the classical setting, we show that any such deterministic scheme can be used as a black box to build a randomized bit-encryption scheme that is no longer susceptible to this attack.
Efficient secure-channel free public key encryption with keyword search for EMRs in cloud storage.
Guo, Lifeng; Yau, Wei-Chuen
2015-02-01
Searchable encryption is an important cryptographic primitive that enables privacy-preserving keyword search on encrypted electronic medical records (EMRs) in cloud storage. Efficiency of such searchable encryption in a medical cloud storage system is very crucial as it involves client platforms such as smartphones or tablets that only have constrained computing power and resources. In this paper, we propose an efficient secure-channel free public key encryption with keyword search (SCF-PEKS) scheme that is proven secure in the standard model. We show that our SCF-PEKS scheme is not only secure against chosen keyword and ciphertext attacks (IND-SCF-CKCA), but also secure against keyword guessing attacks (IND-KGA). Furthermore, our proposed scheme is more efficient than other recent SCF-PEKS schemes in the literature.
Symmetries and security of a quantum-public-key encryption based on single-qubit rotations
NASA Astrophysics Data System (ADS)
Seyfarth, U.; Nikolopoulos, G. M.; Alber, G.
2012-02-01
Exploring the symmetries underlying a previously proposed encryption scheme that relies on single-qubit rotations, we derive an improved upper bound on the maximum information that an eavesdropper might extract from all the available copies of the public key. Subsequently, the robustness of the scheme is investigated in the context of attacks that address each public-key qubit independently. The attacks under consideration make use of projective measurements on single qubits and their efficiency is compared to attacks that address many qubits collectively and require complicated quantum operations.
Guo, Rui; Wen, Qiaoyan; Shi, Huixian; Jin, Zhengping; Zhang, Hua
2013-10-01
Telecare Medicine Information Systems (TMIS) promote the traditional medical and healthcare services by information and communication technology. Since the physician and caregiver can monitor the patient's physiological condition remotely in TMIS, the confidentiality of this sensitive data should be protected, which is the key issue in the Health Insurance Portability and Accountability Act. In this paper, we propose an efficient certificateless public key encryption scheme without bilinear pairing for TMIS. Our proposal is proved to be secure in the random oracle model under the hardness assumption of computational Diffie-Hellman problem. Moreover, after modifying the original model of the certificateless encryption, this scheme achieves Girault's trust level 3. Compared with the related protocols, the perform evaluations show that our scheme is more efficient and appropriate to collocate with low power mobile devices for TMIS.
An improved coding technique for image encryption and key management
NASA Astrophysics Data System (ADS)
Wu, Xu; Ma, Jie; Hu, Jiasheng
2005-02-01
An improved chaotic algorithm for image encryption on the basis of conventional chaotic encryption algorithm is proposed. Two keys are presented in our technique. One is called private key, which is fixed and protected in the system. The other is named assistant key, which is public and transferred with the encrypted image together. For different original image, different assistant key should be chosen so that one could get different encrypted key. The updated encryption algorithm not only can resist a known-plaintext attack, but also offers an effective solution for key management. The analyses and the computer simulations show that the security is improved greatly, and can be easily realized with hardware.
Munisamy, Shyamala Devi; Chokkalingam, Arun
2015-01-01
Cloud computing has pioneered the emerging world by manifesting itself as a service through internet and facilitates third party infrastructure and applications. While customers have no visibility on how their data is stored on service provider's premises, it offers greater benefits in lowering infrastructure costs and delivering more flexibility and simplicity in managing private data. The opportunity to use cloud services on pay-per-use basis provides comfort for private data owners in managing costs and data. With the pervasive usage of internet, the focus has now shifted towards effective data utilization on the cloud without compromising security concerns. In the pursuit of increasing data utilization on public cloud storage, the key is to make effective data access through several fuzzy searching techniques. In this paper, we have discussed the existing fuzzy searching techniques and focused on reducing the searching time on the cloud storage server for effective data utilization. Our proposed Asymmetric Classifier Multikeyword Fuzzy Search method provides classifier search server that creates universal keyword classifier for the multiple keyword request which greatly reduces the searching time by learning the search path pattern for all the keywords in the fuzzy keyword set. The objective of using BTree fuzzy searchable index is to resolve typos and representation inconsistencies and also to facilitate effective data utilization.
Encrypting Digital Camera with Automatic Encryption Key Deletion
NASA Technical Reports Server (NTRS)
Oakley, Ernest C. (Inventor)
2007-01-01
A digital video camera includes an image sensor capable of producing a frame of video data representing an image viewed by the sensor, an image memory for storing video data such as previously recorded frame data in a video frame location of the image memory, a read circuit for fetching the previously recorded frame data, an encryption circuit having an encryption key input connected to receive the previously recorded frame data from the read circuit as an encryption key, an un-encrypted data input connected to receive the frame of video data from the image sensor and an encrypted data output port, and a write circuit for writing a frame of encrypted video data received from the encrypted data output port of the encryption circuit to the memory and overwriting the video frame location storing the previously recorded frame data.
NASA Astrophysics Data System (ADS)
Meng, X. F.; Peng, X.; Cai, L. Z.; Li, A. M.; Gao, Z.; Wang, Y. R.
2009-08-01
A hybrid cryptosystem is proposed, in which one image is encrypted to two interferograms with the aid of double random-phase encoding (DRPE) and two-step phase-shifting interferometry (2-PSI), then three pairs of public-private keys are utilized to encode and decode the session keys (geometrical parameters, the second random-phase mask) and interferograms. In the stage of decryption, the ciphered image can be decrypted by wavefront reconstruction, inverse Fresnel diffraction, and real amplitude normalization. This approach can successfully solve the problem of key management and dispatch, resulting in increased security strength. The feasibility of the proposed cryptosystem and its robustness against some types of attack are verified and analyzed by computer simulations.
Key management for large scale end-to-end encryption
Witzke, E.L.
1994-07-01
Symmetric end-to-end encryption requires separate keys for each pair of communicating confidants. This is a problem of Order N{sup 2}. Other factors, such as multiple sessions per pair of confidants and multiple encryption points in the ISO Reference Model complicate key management by linear factors. Public-key encryption can reduce the number of keys managed to a linear problem which is good for scaleability of key management, but comes with complicating issues and performance penalties. Authenticity is the primary ingredient of key management. If each potential pair of communicating confidants can authenticate data from each other, then any number of public encryption keys of any type can be communicated with requisite integrity. These public encryption keys can be used with the corresponding private keys to exchange symmetric cryptovariables for high data rate privacy protection. The Digital Signature Standard (DSS), which has been adopted by the United States Government, has both public and private components, similar to a public-key cryptosystem. The Digital Signature Algorithm of the DSS is intended for authenticity but not for secrecy. In this paper, the authors will show how the use of the Digital Signature Algorithm combined with both symmetric and asymmetric (public-key) encryption techniques can provide a practical solution to key management scaleability problems, by reducing the key management complexity to a problem of order N, without sacrificing the encryption speed necessary to operate in high performance networks.
Method for encryption and transmission of digital keying data
Mniszewski, S.M.; Springer, E.A.; Brenner, D.P.
1988-03-29
A cryptographic method for encrypting, transmitting and decrypting keying data between a master unit and at least one remote unit is described comprising the steps of: storing in the master unit and in the remote unit key encryption keys, generating a first storage address effective to identify a master key encryption key from the key encryption keys; indexing the first storage address by a first predetermined amount to define a second storage address effective to identify a first key encryption key from the key encryption keys; indexing the first storage address by a second predetermined amount to define a third storage address effective to identify a second key encryption key from the key encryption keys; generating a data encryption key in the master unit, using the first key encryption key; encrypting the data encryption key using the second key encryption key to produce an encrypted data encryption key; downloading to the remote unit the encrypted data encryption key together with a designator value for identifying the address of the second key encryption key at the remote unit; and decrypting the encrypted data encryption key at the remote unit to reproduce the data encryption key at the remote unit.
Method for encryption and transmission of digital keying data
Mniszewski, Susan M.; Springer, Edward A.; Brenner, David P.
1988-01-01
A method for the encryption, transmission, and subsequent decryption of digital keying data. The method utilizes the Data Encryption Standard and is implemented by means of a pair of apparatus, each of which is selectable to operate as either a master unit or remote unit. Each unit contains a set of key encryption keys which are indexed by a common indexing system. The master unit operates upon command from the remote unit to generate a data encryption key and encrypt the data encryption key using a preselected key encryption key. The encrypted data encryption key and an index designator are then downloaded to the remote unit, where the data encryption key is decrypted for subsequent use in the encryption and transmission data. Downloading of the encrypted data encryption key enables frequent change of keys without requiring manual entry or storage of keys at the remote unit.
New Security Results on Encrypted Key Exchange
Bresson, Emmanuel; Chevassut, Olivier; Pointcheval, David
2003-12-15
Schemes for encrypted key exchange are designed to provide two entities communicating over a public network, and sharing a (short) password only, with a session key to be used to achieve data integrity and/or message confidentiality. An example of a very efficient and ''elegant'' scheme for encrypted key exchange considered for standardization by the IEEE P1363 Standard working group is AuthA. This scheme was conjectured secure when the symmetric-encryption primitive is instantiated via either a cipher that closely behaves like an ''ideal cipher,'' or a mask generation function that is the product of the message with a hash of the password. While the security of this scheme in the former case has been recently proven, the latter case was still an open problem. For the first time we prove in this paper that this scheme is secure under the assumptions that the hash function closely behaves like a random oracle and that the computational Diffie-Hellman problem is difficult. Furthermore, since Denial-of-Service (DoS) attacks have become a common threat we enhance AuthA with a mechanism to protect against them.
Encryption key distribution via chaos synchronization
Keuninckx, Lars; Soriano, Miguel C.; Fischer, Ingo; Mirasso, Claudio R.; Nguimdo, Romain M.; Van der Sande, Guy
2017-01-01
We present a novel encryption scheme, wherein an encryption key is generated by two distant complex nonlinear units, forced into synchronization by a chaotic driver. The concept is sufficiently generic to be implemented on either photonic, optoelectronic or electronic platforms. The method for generating the key bitstream from the chaotic signals is reconfigurable. Although derived from a deterministic process, the obtained bit series fulfill the randomness conditions as defined by the National Institute of Standards test suite. We demonstrate the feasibility of our concept on an electronic delay oscillator circuit and test the robustness against attacks using a state-of-the-art system identification method. PMID:28233876
Encryption key distribution via chaos synchronization.
Keuninckx, Lars; Soriano, Miguel C; Fischer, Ingo; Mirasso, Claudio R; Nguimdo, Romain M; Van der Sande, Guy
2017-02-24
We present a novel encryption scheme, wherein an encryption key is generated by two distant complex nonlinear units, forced into synchronization by a chaotic driver. The concept is sufficiently generic to be implemented on either photonic, optoelectronic or electronic platforms. The method for generating the key bitstream from the chaotic signals is reconfigurable. Although derived from a deterministic process, the obtained bit series fulfill the randomness conditions as defined by the National Institute of Standards test suite. We demonstrate the feasibility of our concept on an electronic delay oscillator circuit and test the robustness against attacks using a state-of-the-art system identification method.
The classification of quantum symmetric-key encryption protocols
NASA Astrophysics Data System (ADS)
Xiang, Chong; Yang, Li; Peng, Yong; Chen, Dongqing
2014-11-01
The classification of quantum symmetric-key encryption protocol is presented. According to five elements of a quantum symmetric-key encryption protocol: plaintext, ciphertext, key, encryption algorithm and decryption algorithm, there are 32 different kinds of them. Among them, 5 kinds of protocols have already been constructed and studied, and 21 kinds of them are proved to be impossible to construct, the last 6 kinds of them are not yet presented effectively. That means the research on quantum symmetric-key encryption protocol only needs to consider with 5 kinds of them nowadays.
A Contents Encryption Mechanism Using Reused Key in IPTV
NASA Astrophysics Data System (ADS)
Jeong, Yoon-Su; Kim, Yong-Tae; Cho, Young-Bok; Lee, Ki-Jeong; Park, Gil-Cheol; Lee, Sang-Ho
Recently IPTV is being spotlighted as a new stream service to stably provide video, audio and control signals to subscribers through the application of IP protocol. However, the IPTV system is facing more security threats than the traditional TV. This study proposes a multicasting encryption mechanism for secure transmission of the contents of IPTV by which the content provider encrypts their contents and send the encrypted contents and the key used for encryption of the contents to the user. In order to reduce the time and cost of Head-End, the proposed mechanism encrypts the media contents at the Head-End, embeds the code of the IPTV terminal used at the Head-End in the media contents for user tracking, and performs desynchronization for protection of the media contents from various attacks.
Public Key Infrastructure Study
1994-04-01
whom it was created. This may require that the ORA load the certificate onto a smart card or floppy disk. The ORA has no authority to generate...appropriate directory server and, possibly, sent to the ORA to be loaded onto the user’s disk, smart card or other token. Adding another PCA, adding a new CA...possibly on a smart card , a PCMCIA card or an encrypted diskette. He is also responsible for having his public key certified by a CA. 5-2 To have his
Quantum cryptography using coherent states: Randomized encryption and key generation
NASA Astrophysics Data System (ADS)
Corndorf, Eric
With the advent of the global optical-telecommunications infrastructure, an increasing number of individuals, companies, and agencies communicate information with one another over public networks or physically-insecure private networks. While the majority of the traffic flowing through these networks requires little or no assurance of secrecy, the same cannot be said for certain communications between banks, between government agencies, within the military, and between corporations. In these arenas, the need to specify some level of secrecy in communications is a high priority. While the current approaches to securing sensitive information (namely the public-key-cryptography infrastructure and deterministic private-key ciphers like AES and 3DES) seem to be cryptographically strong based on empirical evidence, there exist no mathematical proofs of secrecy for any widely deployed cryptosystem. As an example, the ubiquitous public-key cryptosystems infer all of their secrecy from the assumption that factoring of the product of two large primes is necessarily time consuming---something which has not, and perhaps cannot, be proven. Since the 1980s, the possibility of using quantum-mechanical features of light as a physical mechanism for satisfying particular cryptographic objectives has been explored. This research has been fueled by the hopes that cryptosystems based on quantum systems may provide provable levels of secrecy which are at least as valid as quantum mechanics itself. Unfortunately, the most widely considered quantum-cryptographic protocols (BB84 and the Ekert protocol) have serious implementation problems. Specifically, they require quantum-mechanical states which are not readily available, and they rely on unproven relations between intrusion-level detection and the information available to an attacker. As a result, the secrecy level provided by these experimental implementations is entirely unspecified. In an effort to provably satisfy the cryptographic
Dual key speech encryption algorithm based underdetermined BSS.
Zhao, Huan; He, Shaofang; Chen, Zuo; Zhang, Xixiang
2014-01-01
When the number of the mixed signals is less than that of the source signals, the underdetermined blind source separation (BSS) is a significant difficult problem. Due to the fact that the great amount data of speech communications and real-time communication has been required, we utilize the intractability of the underdetermined BSS problem to present a dual key speech encryption method. The original speech is mixed with dual key signals which consist of random key signals (one-time pad) generated by secret seed and chaotic signals generated from chaotic system. In the decryption process, approximate calculation is used to recover the original speech signals. The proposed algorithm for speech signals encryption can resist traditional attacks against the encryption system, and owing to approximate calculation, decryption becomes faster and more accurate. It is demonstrated that the proposed method has high level of security and can recover the original signals quickly and efficiently yet maintaining excellent audio quality.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-07
...;having general applicability and legal effect, most of which are keyed #0;to and codified in the Code of Federal Regulations, which is published #0;under 50 titles pursuant to 44 U.S.C. 1510. #0; #0;The Code of... Software and Other Specified Publicly Available Encryption Software in Object Code AGENCY: Bureau...
Efficient multiparty quantum key agreement protocol based on commutative encryption
NASA Astrophysics Data System (ADS)
Sun, Zhiwei; Huang, Jiwu; Wang, Ping
2016-05-01
A secure multiparty quantum key agreement protocol using single-qubit states is proposed. The agreement key is computed by performing exclusive-OR operation on all the participants' secret keys. Based on the commutative property of the commutative encryption, the exclusive-OR operation can be performed on the plaintext in the encrypted state without decrypting it. Thus, it not only protects the final shared key, but also reduces the complexity of the computation. The efficiency of the proposed protocol, compared with previous multiparty QKA protocols, is also improved. In the presented protocol, entanglement states, joint measurement and even the unitary operations are not needed, and only rotation operations and single-state measurement are required, which are easier to be realized with current technology.
Key management and encryption under the bounded storage model.
Draelos, Timothy John; Neumann, William Douglas; Lanzone, Andrew J.; Anderson, William Erik
2005-11-01
There are several engineering obstacles that need to be solved before key management and encryption under the bounded storage model can be realized. One of the critical obstacles hindering its adoption is the construction of a scheme that achieves reliable communication in the event that timing synchronization errors occur. One of the main accomplishments of this project was the development of a new scheme that solves this problem. We show in general that there exist message encoding techniques under the bounded storage model that provide an arbitrarily small probability of transmission error. We compute the maximum capacity of this channel using the unsynchronized key-expansion as side-channel information at the decoder and provide tight lower bounds for a particular class of key-expansion functions that are pseudo-invariant to timing errors. Using our results in combination with Dziembowski et al. [11] encryption scheme we can construct a scheme that solves the timing synchronization error problem. In addition to this work we conducted a detailed case study of current and future storage technologies. We analyzed the cost, capacity, and storage data rate of various technologies, so that precise security parameters can be developed for bounded storage encryption schemes. This will provide an invaluable tool for developing these schemes in practice.
NASA Astrophysics Data System (ADS)
Bondareva, A. P.; Cheremkhin, P. A.; Evtikhiev, N. N.; Krasnov, V. V.; Molodtsov, D. Yu; Nalegaev, S. S.
2016-08-01
Optical encryption and numerical decryption of series of test images using a set of different encryption keys is carried out using scheme operating with spatially-incoherent illumination based on two LC SLMs. Results of experiments on images optical encryption and numerical decryption are presented. Satisfactory average decryption error over 49 encrypted images equal to 0.20±0.05 is achieved.
Quantum Public-Key Cryptosystem
NASA Astrophysics Data System (ADS)
Luo, Ming-Xing; Chen, Xiu-Bo; Yun, Deng; Yang, Yi-Xian
2012-03-01
Quantum one-way functions play a fundamental role in cryptography because of its necessity for the secure encryption schemes taking into account the quantum computer. In this paper our purpose is to establish a theoretical framework for a candidate of the quantum one-way functions and quantum trapdoor functions based on one-parameter unitary groups. The dynamics of parameterized unitary groups ensure the one-wayness and quantum undistinguishability in different levels, and the physical feasibility are derived from the simultaneous approximation of its infinitesimal generators. Moreover, these special functions are used to construct new cryptosystems-the quantum public-key cryptosystems for encrypting both the classical and quantum information.
Security enhanced optical encryption system by random phase key and permutation key.
He, Mingzhao; Tan, Qiaofeng; Cao, Liangcai; He, Qingsheng; Jin, Guofan
2009-12-07
Conventional double random phase encoding (DRPE) encrypts plaintext to white noise-like ciphertext which may attract attention of eavesdroppers, and recent research reported that DRPE is vulnerable to various attacks. Here we propose a security enhanced optical encryption system that can hide the existence of secret information by watermarking. The plaintext is encrypted using iterative fractional Fourier transform with random phase key, and ciphertext is randomly permuted with permutation key before watermarking. Cryptanalysis shows that linearity of the security system has been broken and the permutation key prevent the attacker from accessing the ciphertext in various attacks. A series of simulations have shown the effectiveness of this system and the security strength is enhanced for invisibility, nonlinearity and resistance against attacks.
Sarkadi, Tamás; Koppa, Pál
2012-02-20
In the increasing number of system approaches published in the field of optical encryption, the security level of the system is evaluated by qualitative and empirical methods. To quantify the security of the optical system, we propose to use the equivalent of the key length routinely used in algorithmic encryption. We provide a calculation method of the number of independent keys and deduce the binary key length for optical data encryption. We then investigate and optimize the key length of the combined phase- and amplitude-modulated key encryption in the holographic storage environment, which is one of the promising solutions for the security enhancement of single- and double-random phase-encoding encryption and storage systems. We show that a substantial growth of the key length can be achieved by optimized phase and amplitude modulation compared to phase-only encryption. We also provide experimental confirmation of the model results.
NASA Astrophysics Data System (ADS)
Metwaly, A. F.; Rashad, M. Z.; Omara, F. A.; Megahed, A. A.
2014-06-01
Multicasting refers to the transmission of a message or information from one sender to multiple receivers simultaneously. Although encryption algorithms can be used to secure transmitted messages among group members, still there are many security aspects for designing a secured multicast cryptosystem. The most important aspects of Multicasting are key generation and management. The researchers have proposed several approaches for solving problems of multicast key distribution and management. In this paper, a secure key generation and distribution solution has been proposed for a single host sending to two or more (N) receivers using centralized Quantum Multicast Key Distribution Centre "QMKDC" and classical symmetric encryption. The proposed scheme uses symmetric classical algorithms for encryption and decryption transmitted messages among multicast group members, but the generated keys which are used for authentication, encryption and decryption also play an important role for designing a secured multicast cryptosystem come from QKD protocols. Authentication verified using EPR entangled Photons and controlled-NOT gate. Multiple requests for initialization as well for transmitting sensitive information handled through priority and sensitivity levels. Multiple members' communication is achieved with full or partial support of QMKDC.
NASA Astrophysics Data System (ADS)
Zhang, Long; Sun, Hong-Wei; Zhang, Ke-Jia; Jia, Heng-Yue
2017-03-01
In this paper, a new quantum encryption based on the key-controlled chained CNOT operations, which is named KCCC encryption, is proposed. With the KCCC encryption, an improved arbitrated quantum signature (AQS) protocol is presented. Compared with the existing protocols, our protocol can effectively prevent forgery attacks and disavowal attacks. Moreover, only single state is required in the protocol. We hope it is helpful to further research in the design of AQS protocols in future.
Quantum walk public-key cryptographic system
NASA Astrophysics Data System (ADS)
Vlachou, C.; Rodrigues, J.; Mateus, P.; Paunković, N.; Souto, A.
2015-12-01
Quantum Cryptography is a rapidly developing field of research that benefits from the properties of Quantum Mechanics in performing cryptographic tasks. Quantum walks are a powerful model for quantum computation and very promising for quantum information processing. In this paper, we present a quantum public-key cryptographic system based on quantum walks. In particular, in the proposed protocol the public-key is given by a quantum state generated by performing a quantum walk. We show that the protocol is secure and analyze the complexity of public key generation and encryption/decryption procedures.
Encryption Devices for Use in a Conditional Access System
2007-11-02
cipher such as the well-known DES algorithm . Each elementary stream may be individually encrypted and the resulting encrypted streams ...data stream TDS encrypted control word (CW) E.sub.MSK (CW). The encrypted CW is processed in decryptor 236 using multi-session key MSK as the decryption ...the encryption is done using the well-known RSA public key encryption algorithm . As shown in DHCT 333, EMM 315 can only be decrypted by the
Practical and Secure Recovery of Disk Encryption Key Using Smart Cards
NASA Astrophysics Data System (ADS)
Omote, Kazumasa; Kato, Kazuhiko
In key-recovery methods using smart cards, a user can recover the disk encryption key in cooperation with the system administrator, even if the user has lost the smart card including the disk encryption key. However, the disk encryption key is known to the system administrator in advance in most key-recovery methods. Hence user's disk data may be read by the system administrator. Furthermore, if the disk encryption key is not known to the system administrator in advance, it is difficult to achieve a key authentication. In this paper, we propose a scheme which enables to recover the disk encryption key when the user's smart card is lost. In our scheme, the disk encryption key is not preserved anywhere and then the system administrator cannot know the key before key-recovery phase. Only someone who has a user's smart card and knows the user's password can decrypt that user's disk data. Furthermore, we measured the processing time required for user authentication in an experimental environment using a virtual machine monitor. As a result, we found that this processing time is short enough to be practical.
Public/private key certification authority and key distribution. Draft
Long, J.P.; Christensen, M.J.; Sturtevant, A.P.; Johnston, W.E.
1995-09-25
Traditional encryption, which protects messages from prying eyes, has been used for many decades. The present concepts of encryption are built from that heritage. Utilization of modern software-based encryption techniques implies much more than simply converting files to an unreadable form. Ubiquitous use of computers and advances in encryption technology coupled with the use of wide-area networking completely changed the reasons for utilizing encryption technology. The technology demands a new and extensive infrastructure to support these functions. Full understanding of these functions, their utility and value, and the need for an infrastructure, takes extensive exposure to the new paradigm. This paper addresses issues surrounding the establishment and operation of a key management system (i.e., certification authority) that is essential to the successful implementation and wide-spread use of encryption.
Hymel, Ross
2013-07-25
The Public Key (PK) FPGA software performs asymmetric authentication using the 163-bit Elliptic Curve Digital Signature Algorithm (ECDSA) on an embedded FPGA platform. A digital signature is created on user-supplied data, and communication with a host system is performed via a Serial Peripheral Interface (SPI) bus. Software includes all components necessary for signing, including custom random number generator for key creation and SHA-256 for data hashing.
Field test of classical symmetric encryption with continuous variables quantum key distribution.
Jouguet, Paul; Kunz-Jacques, Sébastien; Debuisschert, Thierry; Fossier, Simon; Diamanti, Eleni; Alléaume, Romain; Tualle-Brouri, Rosa; Grangier, Philippe; Leverrier, Anthony; Pache, Philippe; Painchault, Philippe
2012-06-18
We report on the design and performance of a point-to-point classical symmetric encryption link with fast key renewal provided by a Continuous Variable Quantum Key Distribution (CVQKD) system. Our system was operational and able to encrypt point-to-point communications during more than six months, from the end of July 2010 until the beginning of February 2011. This field test was the first demonstration of the reliability of a CVQKD system over a long period of time in a server room environment. This strengthens the potential of CVQKD for information technology security infrastructure deployments.
NASA Astrophysics Data System (ADS)
Zhao, Tieyu; Ran, Qiwen; Yuan, Lin; Chi, Yingying; Ma, Jing
2016-08-01
A novel image encryption system based on double random phase encoding (DRPE) and RSA public-key algorithm is proposed. The main characteristic of the system is that each encryption process produces a new decryption key (even for the same plaintext), thus the encryption system conforms to the feature of the one-time pad (OTP) cryptography. The other characteristic of the system is the use of fingerprint key. Only with the rightful authorization will the true decryption be obtained, otherwise the decryption will result in noisy images. So the proposed system can be used to determine whether the ciphertext is falsified by attackers. In addition, the system conforms to the basic agreement of asymmetric cryptosystem (ACS) due to the combination with the RSA public-key algorithm. The simulation results show that the encryption scheme has high robustness against the existing attacks.
Chaotic Image Encryption Based on Running-Key Related to Plaintext
Guanghui, Cao; Kai, Hu; Yizhi, Zhang; Jun, Zhou; Xing, Zhang
2014-01-01
In the field of chaotic image encryption, the algorithm based on correlating key with plaintext has become a new developing direction. However, for this kind of algorithm, some shortcomings in resistance to reconstruction attack, efficient utilization of chaotic resource, and reducing dynamical degradation of digital chaos are found. In order to solve these problems and further enhance the security of encryption algorithm, based on disturbance and feedback mechanism, we present a new image encryption scheme. In the running-key generation stage, by successively disturbing chaotic stream with cipher-text, the relation of running-key to plaintext is established, reconstruction attack is avoided, effective use of chaotic resource is guaranteed, and dynamical degradation of digital chaos is minimized. In the image encryption stage, by introducing random-feedback mechanism, the difficulty of breaking this scheme is increased. Comparing with the-state-of-the-art algorithms, our scheme exhibits good properties such as large key space, long key period, and extreme sensitivity to the initial key and plaintext. Therefore, it can resist brute-force, reconstruction attack, and differential attack. PMID:24711727
Chaotic image encryption based on running-key related to plaintext.
Guanghui, Cao; Kai, Hu; Yizhi, Zhang; Jun, Zhou; Xing, Zhang
2014-01-01
In the field of chaotic image encryption, the algorithm based on correlating key with plaintext has become a new developing direction. However, for this kind of algorithm, some shortcomings in resistance to reconstruction attack, efficient utilization of chaotic resource, and reducing dynamical degradation of digital chaos are found. In order to solve these problems and further enhance the security of encryption algorithm, based on disturbance and feedback mechanism, we present a new image encryption scheme. In the running-key generation stage, by successively disturbing chaotic stream with cipher-text, the relation of running-key to plaintext is established, reconstruction attack is avoided, effective use of chaotic resource is guaranteed, and dynamical degradation of digital chaos is minimized. In the image encryption stage, by introducing random-feedback mechanism, the difficulty of breaking this scheme is increased. Comparing with the-state-of-the-art algorithms, our scheme exhibits good properties such as large key space, long key period, and extreme sensitivity to the initial key and plaintext. Therefore, it can resist brute-force, reconstruction attack, and differential attack.
Optical image encryption using password key based on phase retrieval algorithm
NASA Astrophysics Data System (ADS)
Zhao, Tieyu; Ran, Qiwen; Yuan, Lin; Chi, Yingying; Ma, Jing
2016-04-01
A novel optical image encryption system is proposed using password key based on phase retrieval algorithm (PRA). In the encryption process, a shared image is taken as a symmetric key and the plaintext is encoded into the phase-only mask based on the iterative PRA. The linear relationship between the plaintext and ciphertext is broken using the password key, which can resist the known plaintext attack. The symmetric key and the retrieved phase are imported into the input plane and Fourier plane of 4f system during the decryption, respectively, so as to obtain the plaintext on the CCD. Finally, we analyse the key space of the password key, and the results show that the proposed scheme can resist a brute force attack due to the flexibility of the password key.
Controlled order rearrangement encryption for quantum key distribution
Deng Fuguo; Long, G.L.
2003-10-01
A technique is devised to perform orthogonal state quantum key distribution. In this scheme, entangled parts of a quantum information carrier are sent from Alice to Bob through two quantum channels. However, before the transmission, the order of the quantum information carrier in one channel is reordered so that Eve cannot steal useful information. At the receiver's end, the order of the quantum information carrier is restored. The order rearrangement operation in both parties is controlled by a prior shared control key which is used repeatedly in a quantum key distribution session.
NASA Astrophysics Data System (ADS)
Cui, Yue; Zhang, Min; Zhan, Yueying; Wang, Danshi; Huang, Shanguo
2016-08-01
A scheme for optical parallel encryption/decryption of quadrature phase shift keying (QPSK) signals is proposed, in which three QPSK signals at 10 Gb/s are encrypted and decrypted simultaneously in the optical domain through nondegenerate four-wave mixing in a highly nonlinear fiber. The results of theoretical analysis and simulations show that the scheme can perform high-speed wiretapping against the encryption of parallel signals and receiver sensitivities of encrypted signal and the decrypted signal are -25.9 and -23.8 dBm, respectively, at the forward error correction threshold. The results are useful for designing high-speed encryption/decryption of advanced modulated signals and thus enhancing the physical layer security of optical networks.
A public-key cryptosystem for quantum message transmission
NASA Astrophysics Data System (ADS)
Yang, Li
2005-01-01
We present a quantum public-key cryptography protocol for quantum message transmission. The private key of this protocol includes three classical matrices: a generator matrix of a Goppa code, an invertible matrix and a permutation matrix. The public key is product of these three matrices. The encryption and decryption algorithms are merely quantum computations related with the transformations between bases of the quantum registers. The security of this protocol is based on the hypothesis that there is no effective algorithm of NP-complete problem.
NASA Astrophysics Data System (ADS)
Zhou, Nanrun; Zhang, Aidi; Zheng, Fen; Gong, Lihua
2014-10-01
The existing ways to encrypt images based on compressive sensing usually treat the whole measurement matrix as the key, which renders the key too large to distribute and memorize or store. To solve this problem, a new image compression-encryption hybrid algorithm is proposed to realize compression and encryption simultaneously, where the key is easily distributed, stored or memorized. The input image is divided into 4 blocks to compress and encrypt, then the pixels of the two adjacent blocks are exchanged randomly by random matrices. The measurement matrices in compressive sensing are constructed by utilizing the circulant matrices and controlling the original row vectors of the circulant matrices with logistic map. And the random matrices used in random pixel exchanging are bound with the measurement matrices. Simulation results verify the effectiveness, security of the proposed algorithm and the acceptable compression performance.
Channel-Based Key Generation for Encrypted Body-Worn Wireless Sensor Networks
Van Torre, Patrick
2016-01-01
Body-worn sensor networks are important for rescue-workers, medical and many other applications. Sensitive data are often transmitted over such a network, motivating the need for encryption. Body-worn sensor networks are deployed in conditions where the wireless communication channel varies dramatically due to fading and shadowing, which is considered a disadvantage for communication. Interestingly, these channel variations can be employed to extract a common encryption key at both sides of the link. Legitimate users share a unique physical channel and the variations thereof provide data series on both sides of the link, with highly correlated values. An eavesdropper, however, does not share this physical channel and cannot extract the same information when intercepting the signals. This paper documents a practical wearable communication system implementing channel-based key generation, including an implementation and a measurement campaign comprising indoor as well as outdoor measurements. The results provide insight into the performance of channel-based key generation in realistic practical conditions. Employing a process known as key reconciliation, error free keys are generated in all tested scenarios. The key-generation system is computationally simple and therefore compatible with the low-power micro controllers and low-data rate transmissions commonly used in wireless sensor networks. PMID:27618051
Channel-Based Key Generation for Encrypted Body-Worn Wireless Sensor Networks.
Van Torre, Patrick
2016-09-08
Body-worn sensor networks are important for rescue-workers, medical and many other applications. Sensitive data are often transmitted over such a network, motivating the need for encryption. Body-worn sensor networks are deployed in conditions where the wireless communication channel varies dramatically due to fading and shadowing, which is considered a disadvantage for communication. Interestingly, these channel variations can be employed to extract a common encryption key at both sides of the link. Legitimate users share a unique physical channel and the variations thereof provide data series on both sides of the link, with highly correlated values. An eavesdropper, however, does not share this physical channel and cannot extract the same information when intercepting the signals. This paper documents a practical wearable communication system implementing channel-based key generation, including an implementation and a measurement campaign comprising indoor as well as outdoor measurements. The results provide insight into the performance of channel-based key generation in realistic practical conditions. Employing a process known as key reconciliation, error free keys are generated in all tested scenarios. The key-generation system is computationally simple and therefore compatible with the low-power micro controllers and low-data rate transmissions commonly used in wireless sensor networks.
Comment on the "Quantum Public-Key Cryptosystem"
NASA Astrophysics Data System (ADS)
Zhou, Ri-gui; Li, Wei; Huan, Tian-tian
2015-03-01
In 2012, Luo et al. proposed a new quantum public-key cryptosystems, which can encrypt both the classical and quantum information. (Luo et al. Int. J. Theor. Phys. 51(3), 912-924, 2012). However, it cannot be realized because there are some mistakes in the calculation and design process. This paper points out these failures and proposes an improvement to avoid the loophole.
High efficient key-insulated attribute based encryption scheme without bilinear pairing operations.
Hong, Hanshu; Sun, Zhixin
2016-01-01
Attribute based encryption (ABE) has been widely applied for secure data protection in various data sharing systems. However, the efficiency of existing ABE schemes is not high enough since running encrypt and decrypt algorithms need frequent bilinear pairing operations, which may occupy too much computing resources on terminal devices. What's more, since different users may share the same attributes in the system, a single user's private key exposure will threaten the security and confidentiality of the whole system. Therefore, to further decrease the computation cost in attribute based cryptosystem as well as provide secure protection when key exposure happens, in this paper, we firstly propose a high efficient key-insulated ABE algorithm without pairings. The key-insulated mechanism guarantees both forward security and backward security when key exposure or user revocation happens. Besides, during the running of algorithms in our scheme, users and attribute authority needn't run any bilinear pairing operations, which will increase the efficiency to a large extent. The high efficiency and security analysis indicate that our scheme is more appropriate for secure protection in data sharing systems.
Physical Cryptography: A New Approach to Key Generation and Direct Encryption
2009-11-18
Std Z39-18 P a g e | 2 Abstract: The security of key generation and direct encryption in quantum and physical cryptography have been...emerging development of classical-noise cryptography [1, 2] and quantum cryptography [3] suggests that a new way of building cryptosystems may be...has been further studied theoretically and P a g e | 4 experimentally to only a limited extent. The second is quantum cryptography [3] based on
Applications of single-qubit rotations in quantum public-key cryptography
NASA Astrophysics Data System (ADS)
Nikolopoulos, Georgios M.
2008-03-01
We discuss cryptographic applications of single-qubit rotations from the perspective of trapdoor one-way functions and public-key encryption. In particular, we present an asymmetric cryptosystem whose security relies on fundamental principles of quantum physics. A quantum public key is used for the encryption of messages while decryption is possible by means of a classical private key only. The trapdoor one-way function underlying the proposed cryptosystem maps integer numbers to quantum states of a qubit and its inversion can be infeasible by virtue of the Holevo’s theorem.
Chaos-based color pathological image encryption scheme using one-time keys.
Liu, Guoyan; Li, Jie; Liu, Hongjun
2014-02-01
This paper proposes an improved chaos-based color pathological image encryption algorithm, using SHA-2 to generate one-time keys. In order to send different ciphered images to different recipients, the hash value of the plain image and a random number are applied to generate one-time initial conditions for Chebyshev maps, to make the key stream change in every confusion process without changing the common initial values. The permuted image is divided into 256-bit long blocks, the avalanche effect is applied to diffuse the blocks, i.e., each block is XORed with the hash value of the prior block. Simulation results demonstrate that the proposed algorithm is robust against common attacks.
Modeling, Simulation and Analysis of Public Key Infrastructure
NASA Technical Reports Server (NTRS)
Liu, Yuan-Kwei; Tuey, Richard; Ma, Paul (Technical Monitor)
1998-01-01
Security is an essential part of network communication. The advances in cryptography have provided solutions to many of the network security requirements. Public Key Infrastructure (PKI) is the foundation of the cryptography applications. The main objective of this research is to design a model to simulate a reliable, scalable, manageable, and high-performance public key infrastructure. We build a model to simulate the NASA public key infrastructure by using SimProcess and MatLab Software. The simulation is from top level all the way down to the computation needed for encryption, decryption, digital signature, and secure web server. The application of secure web server could be utilized in wireless communications. The results of the simulation are analyzed and confirmed by using queueing theory.
KeySlinger and StarSlinger: Secure Key Exchange and Encrypted File Transfer on Smartphones
2011-05-01
being detected . Details of attacks against the exchange protocol itself are described in [2]. They include deleting, modifying, or inserting data...using KeySlinger. It is assumed that signature forgery or file decryption is infeasible without possession of the corresponding RSA private key...signature forgery is infeasible. Potential attacks then are limited to denial of service or spamming. These issues are addressed in Section 6. 3
Experiences of Using a Public Key Infrastructure for the Preparation of Examination Papers.
ERIC Educational Resources Information Center
Chadwick, David W.; Tassabehji, Rana; Young, Andrew
2000-01-01
Describes a project at the University of Salford (United Kingdom) that transferred examination papers between participants (lecturers, administrators and external examiners) using secure electronic mail via a managed public key infrastructure that used encryption methods. Discusses resistance to change and technology problems. (Contains 6…
NASA Astrophysics Data System (ADS)
Weber, Robert E.
2001-11-01
approximately 15 Gigabyte table of IV values can be used to encrypt any packet. On a network only partially infiltrated, bit-wise manipulated packets can spoof their validity using the linear nature of the CSC checksum. Any combination of passive and active attacks can be used to modify commands as they are being sent or login information can be taken for use on another network to access personal accounts. WEP also has a critical flaw outside of the sophisticated attacks that can be used to subvert its security. WEP uses a shared key known by both the client machines and the base stations. For this reason the key can be lost through human security problems. This includes the loss of equipment to theft, employee turnover and general mishandling of key information. In order to implement secure wireless networks it has become clear that a new scheme must be developed which can address the 3 security concerns mentioned earlier and at the same time function on existing hardware and software.
NASA Astrophysics Data System (ADS)
Gil, Sang Keun; Jeon, Seok Hee; Jung, Jong Rae
2013-03-01
We propose a new optical symmetric cryptographic system with simultaneous encryption and transmission of binary data and secret key by using dual phase-shifting digital holography. Dual phase-shifting digital holography contains two inner and outer interferometers which are used for encrypting data and a secret key at the same time. The technique using dual phase-shifting digital holographic interferometry is efficient because this scheme has an advantage of interference fringe data acquiring time. Binary information data is encrypted by the secret key by applying phase-shifting digital holographic method, and this secret key is also encrypted by phase-shifting digital holographic method and transmitted. Encrypted digital hologram in our method is Fourier transform hologram and is recorded on CCD with 256 gray-level quantized intensities. These encrypted digital holograms are able to be stored by computer and be transmitted over a communication network. With this encrypted digital hologram, the original binary data are decrypted by the same secret key. Simulation results show that the proposed method can be used for a cipher and security system.
Amplitude-phase retrieval attack free image encryption based on two random masks and interference
NASA Astrophysics Data System (ADS)
Liansheng, Sui; bei, Zhou; Zhanmin, Wang; qindong, Sun
2016-11-01
An amplitude-phase retrieval attack free encryption scheme is proposed by using two random masks, where one is considered as the random image and other as the public key. Initially, the random image is encrypted to two phase-only masks based on interference technique with the help of the public key. These two phase-only masks are real-valued functions and used as the encryption keys. Then, the plain image is encrypted to the ciphertext with the white noise distribution by using the phase-truncated Fourier-transform-based encoding scheme with the previous encryption keys. The encryption process is nonlinear in which no iterative calculation is involved, while the decryption process is linear which can be easily implemented with the 4 f optical system. Moreover, less constraints makes the specific attack unusable. Simulation results are given to verify the feasibility and robustness of the proposed encryption scheme.
NASA Astrophysics Data System (ADS)
Nikulin, Vladimir V.; Hughes, David H.; Malowicki, John; Bedi, Vijit
2015-05-01
Free-space optical communication channels offer secure links with low probability of interception and detection. Despite their point-to-point topology, additional security features may be required in privacy-critical applications. Encryption can be achieved at the physical layer by using quantized values of photons, which makes exploitation of such quantum communication links extremely difficult. One example of such technology is keyed communication in quantum noise, a novel quantum modulation protocol that offers ultra-secure communication with competitive performance characteristics. Its utilization relies on specific coherent measurements to decrypt the signal. The process of measurements is complicated by the inherent and irreducible quantum noise of coherent states. This problem is different from traditional laser communication with coherent detection; therefore continuous efforts are being made to improve the measurement techniques. Quantum-based encryption systems that use the phase of the signal as the information carrier impose aggressive requirements on the accuracy of the measurements when an unauthorized party attempts intercepting the data stream. Therefore, analysis of the secrecy of the data becomes extremely important. In this paper, we present the results of a study that had a goal of assessment of potential vulnerability of the running key. Basic results of the laboratory measurements are combined with simulation studies and statistical analysis that can be used for both conceptual improvement of the encryption approach and for quantitative comparison of secrecy of different quantum communication protocols.
Applied public-key steganography
NASA Astrophysics Data System (ADS)
Guillon, Pierre; Furon, Teddy; Duhamel, Pierre
2002-04-01
We consider the problem of hiding information in a steganographic framework, i.e. embedding a binary message within an apparently innocuous content, in order to establish a suspicion-free digital communication channel. The adversary is passive as no intentional attack is foreseen. The only threat is that she discovers the presence of a hidden communication. The main goal of this article is to find if the Scalar Costa Scheme, a recently published embedding method exploiting side information at the encoder, is suitable for that framework. We justify its use assessing its security level with respect to the Cachin's criterion. We derive a public-key stego-system following the ideas of R. Anderson and P. Petitcolas. This technique is eventually applied to PCM audio contents. Experimental performances are detailed in terms of bit-rate and Kullback-Leibler distance.
Synchronized chaotic phase masks for encrypting and decrypting images
NASA Astrophysics Data System (ADS)
Rueda, Edgar; Vera, Carlos A.; Rodríguez, Boris; Torroba, Roberto
2008-12-01
This paper presents an alternative to secure exchange of encrypted information through public open channels. Chaotic encryption introduces a security improvement by an efficient masking of the message with a chaotic signal. Message extraction by an authorized end user is done using a synchronization procedure, thus allowing a continuous change of the encrypting and decrypting keys. And optical implementation with a 4f optical encrypting architecture is suggested. Digital simulations, including the effects of missing data, corrupted data and noise addition are shown. These results proof the consistency of the proposal, and demonstrate a practical way to operate with it.
An Identity-Based (IDB) Broadcast Encryption Scheme with Personalized Messages (BEPM).
Xu, Ke; Liao, Yongjian; Qiao, Li; Liu, Zhangyun; Yang, Xiaowei
2015-01-01
A broadcast encryption scheme with personalized messages (BEPM) is a scheme in which a broadcaster transmits not only encrypted broadcast messages to a subset of recipients but also encrypted personalized messages to each user individually. Several broadcast encryption (BE) schemes allow a broadcaster encrypts a message for a subset S of recipients with public keys and any user in S can decrypt the message with his/her private key. However, these BE schemes can not provide an efficient way to transmit encrypted personalized messages to each user individually. In this paper, we propose a broadcast encryption scheme with a transmission of personalized messages. Besides, the scheme is based on multilinear maps ensure constant ciphertext size and private key size of each user and the scheme can achieve statically security. More realistically, the scheme can be applied to the Conditional Access System (CAS) of pay television (pay-TV) efficiently and safely.
An Identity-Based (IDB) Broadcast Encryption Scheme with Personalized Messages (BEPM)
Xu, Ke; Liao, Yongjian; Qiao, Li
2015-01-01
A broadcast encryption scheme with personalized messages (BEPM) is a scheme in which a broadcaster transmits not only encrypted broadcast messages to a subset of recipients but also encrypted personalized messages to each user individually. Several broadcast encryption (BE) schemes allow a broadcaster encrypts a message for a subset S of recipients with public keys and any user in S can decrypt the message with his/her private key. However, these BE schemes can not provide an efficient way to transmit encrypted personalized messages to each user individually. In this paper, we propose a broadcast encryption scheme with a transmission of personalized messages. Besides, the scheme is based on multilinear maps ensure constant ciphertext size and private key size of each user and the scheme can achieve statically security. More realistically, the scheme can be applied to the Conditional Access System (CAS) of pay television (pay-TV) efficiently and safely. PMID:26629817
Phase retrieval encryption in an enhanced optical interference by key phase constraint.
Shi, Xiaoyan; Chen, Ziyang; Zhao, Daomu; Mao, Haidan; Chen, Linfei
2015-04-10
In this paper, we demonstrate a security system by using optical interference and phase retrieval algorithm (PRA) techniques. The modified PRA is proposed to encode the target image into random phase distribution. Optical and digital methods can be used for decryption. By using this method, silhouette elimination is realized. In addition, due to this simplified system design, the iterative rate is improved and the optical decryption realization is easier. Validity and performance of the proposed system are demonstrated by means of numerical simulations. The system encryption capacity as to both binary and gray images is numerically investigated. Then, the decryption procedure is demonstrated by optical experiment means and the decryption result is given.
NASA Astrophysics Data System (ADS)
Tamaki, Kiyoshi; Kato, Go
2010-02-01
One of the simplest security proofs of quantum key distribution is based on the so-called complementarity scenario, which involves the complementarity control of an actual protocol and a virtual protocol [M. Koashi, e-print arXiv:0704.3661 (2007)]. The existing virtual protocol has a limitation in classical postprocessing, i.e., the syndrome for the error-correction step has to be encrypted. In this paper, we remove this limitation by constructing a quantum circuit for the virtual protocol. Moreover, our circuit with a shield system gives an intuitive proof of why adding noise to the sifted key increases the bit error rate threshold in the general case in which one of the parties does not possess a qubit. Thus, our circuit bridges the simple proof and the use of wider classes of classical postprocessing.
Tamaki, Kiyoshi; Kato, Go
2010-02-15
One of the simplest security proofs of quantum key distribution is based on the so-called complementarity scenario, which involves the complementarity control of an actual protocol and a virtual protocol [M. Koashi, e-print arXiv:0704.3661 (2007)]. The existing virtual protocol has a limitation in classical postprocessing, i.e., the syndrome for the error-correction step has to be encrypted. In this paper, we remove this limitation by constructing a quantum circuit for the virtual protocol. Moreover, our circuit with a shield system gives an intuitive proof of why adding noise to the sifted key increases the bit error rate threshold in the general case in which one of the parties does not possess a qubit. Thus, our circuit bridges the simple proof and the use of wider classes of classical postprocessing.
Yang, Yu-Guang; Xu, Peng; Yang, Rui; Zhou, Yi-Hua; Shi, Wei-Min
2016-01-01
Quantum information and quantum computation have achieved a huge success during the last years. In this paper, we investigate the capability of quantum Hash function, which can be constructed by subtly modifying quantum walks, a famous quantum computation model. It is found that quantum Hash function can act as a hash function for the privacy amplification process of quantum key distribution systems with higher security. As a byproduct, quantum Hash function can also be used for pseudo-random number generation due to its inherent chaotic dynamics. Further we discuss the application of quantum Hash function to image encryption and propose a novel image encryption algorithm. Numerical simulations and performance comparisons show that quantum Hash function is eligible for privacy amplification in quantum key distribution, pseudo-random number generation and image encryption in terms of various hash tests and randomness tests. It extends the scope of application of quantum computation and quantum information. PMID:26823196
Yang, Yu-Guang; Xu, Peng; Yang, Rui; Zhou, Yi-Hua; Shi, Wei-Min
2016-01-29
Quantum information and quantum computation have achieved a huge success during the last years. In this paper, we investigate the capability of quantum Hash function, which can be constructed by subtly modifying quantum walks, a famous quantum computation model. It is found that quantum Hash function can act as a hash function for the privacy amplification process of quantum key distribution systems with higher security. As a byproduct, quantum Hash function can also be used for pseudo-random number generation due to its inherent chaotic dynamics. Further we discuss the application of quantum Hash function to image encryption and propose a novel image encryption algorithm. Numerical simulations and performance comparisons show that quantum Hash function is eligible for privacy amplification in quantum key distribution, pseudo-random number generation and image encryption in terms of various hash tests and randomness tests. It extends the scope of application of quantum computation and quantum information.
NASA Astrophysics Data System (ADS)
Yang, Yu-Guang; Xu, Peng; Yang, Rui; Zhou, Yi-Hua; Shi, Wei-Min
2016-01-01
Quantum information and quantum computation have achieved a huge success during the last years. In this paper, we investigate the capability of quantum Hash function, which can be constructed by subtly modifying quantum walks, a famous quantum computation model. It is found that quantum Hash function can act as a hash function for the privacy amplification process of quantum key distribution systems with higher security. As a byproduct, quantum Hash function can also be used for pseudo-random number generation due to its inherent chaotic dynamics. Further we discuss the application of quantum Hash function to image encryption and propose a novel image encryption algorithm. Numerical simulations and performance comparisons show that quantum Hash function is eligible for privacy amplification in quantum key distribution, pseudo-random number generation and image encryption in terms of various hash tests and randomness tests. It extends the scope of application of quantum computation and quantum information.
Modular Integer Arithmetic for Public Key Cryptography
NASA Astrophysics Data System (ADS)
Güneysu, Tim; Paar, Christof
This chapter discusses building blocks for implementing popular public key cryptosystems, like RSA, Diffie-Hellman Key Exchange (DHKE) and Elliptic Curve Cryptography (ECC). Therefore, we briefly introduce field-based arithmetic on which most of recently established public key cryptosystems rely. As most popular fields, we give examples for architecture implementing efficient arithmetic operations over prime and binary extension fields for use in cryptographic applications.
Quantum Secure Dialogue with Quantum Encryption
NASA Astrophysics Data System (ADS)
Ye, Tian-Yu
2014-09-01
How to solve the information leakage problem has become the research focus of quantum dialogue. In this paper, in order to overcome the information leakage problem in quantum dialogue, a novel approach for sharing the initial quantum state privately between communicators, i.e., quantum encryption sharing, is proposed by utilizing the idea of quantum encryption. The proposed protocol uses EPR pairs as the private quantum key to encrypt and decrypt the traveling photons, which can be repeatedly used after rotation. Due to quantum encryption sharing, the public announcement on the state of the initial quantum state is omitted, thus the information leakage problem is overcome. The information-theoretical efficiency of the proposed protocol is nearly 100%, much higher than previous information leakage resistant quantum dialogue protocols. Moreover, the proposed protocol only needs single-photon measurements and nearly uses single photons as quantum resource so that it is convenient to implement in practice.
NASA Astrophysics Data System (ADS)
Tickle, Andrew J.; Sun, Jiajing; Gan, Lu; Smith, Jeremy S.
2008-09-01
In this paper, we discuss a Field Programmable Gate Array (FPGA) implementation of steganography for security applications such as anti-theft systems and forensic investigation systems. Our proposed method takes advantage of both conventional encryption/decryption algorithms and fragile image watermarking techniques to provide user-friendly interface. It could potentially be of benefit to financial investment companies, the military and security forces in order to keep certain information hidden within other content with a change so subtle that no one who does not know exactly where or how to look will not be able to obtain the data. In our proposed system, a steganographic message known as plaintext is first encrypted by conventional methods to give an extra layer of security, producing a ciphertext. The steganographic message can be either an image or ASCII text, both of which will be discussed. Then, the cover text or image is modified to contain the ciphertext, yielding a encrypted text or a watermarked image. Details of the circuitry for each stage are given with some of the encryption and randomization circuitry not included in full detail for commercial reasons. Test images before and after watermarking will be shown to demonstrate the validity and effectiveness of the proposed system.
NASA Technical Reports Server (NTRS)
Jackson, Deborah J. (Inventor)
1998-01-01
An analog optical encryption system based on phase scrambling of two-dimensional optical images and holographic transformation for achieving large encryption keys and high encryption speed. An enciphering interface uses a spatial light modulator for converting a digital data stream into a two dimensional optical image. The optical image is further transformed into a hologram with a random phase distribution. The hologram is converted into digital form for transmission over a shared information channel. A respective deciphering interface at a receiver reverses the encrypting process by using a phase conjugate reconstruction of the phase scrambled hologram.
A joint asymmetric watermarking and image encryption scheme
NASA Astrophysics Data System (ADS)
Boato, G.; Conotter, V.; De Natale, F. G. B.; Fontanari, C.
2008-02-01
Here we introduce a novel watermarking paradigm designed to be both asymmetric, i.e., involving a private key for embedding and a public key for detection, and commutative with a suitable encryption scheme, allowing both to cipher watermarked data and to mark encrypted data without interphering with the detection process. In order to demonstrate the effectiveness of the above principles, we present an explicit example where the watermarking part, based on elementary linear algebra, and the encryption part, exploiting a secret random permutation, are integrated in a commutative scheme.
Multi-Channel Key Agreement Using Encrypted Public Key Exchange (Transcript of Discussion)
NASA Astrophysics Data System (ADS)
Christianson, Bruce
The context for this work is the ubiquitous computing market, where everybody is surrounded by a cloud of little devices that all talk to each other to accomplish various things, and the world we're in is one of talking to strangers.
Public key infrastructure for DOE security research
Aiken, R.; Foster, I.; Johnston, W.E.
1997-06-01
This document summarizes the Department of Energy`s Second Joint Energy Research/Defence Programs Security Research Workshop. The workshop, built on the results of the first Joint Workshop which reviewed security requirements represented in a range of mission-critical ER and DP applications, discussed commonalties and differences in ER/DP requirements and approaches, and identified an integrated common set of security research priorities. One significant conclusion of the first workshop was that progress in a broad spectrum of DOE-relevant security problems and applications could best be addressed through public-key cryptography based systems, and therefore depended upon the existence of a robust, broadly deployed public-key infrastructure. Hence, public-key infrastructure ({open_quotes}PKI{close_quotes}) was adopted as a primary focus for the second workshop. The Second Joint Workshop covered a range of DOE security research and deployment efforts, as well as summaries of the state of the art in various areas relating to public-key technologies. Key findings were that a broad range of DOE applications can benefit from security architectures and technologies built on a robust, flexible, widely deployed public-key infrastructure; that there exists a collection of specific requirements for missing or undeveloped PKI functionality, together with a preliminary assessment of how these requirements can be met; that, while commercial developments can be expected to provide many relevant security technologies, there are important capabilities that commercial developments will not address, due to the unique scale, performance, diversity, distributed nature, and sensitivity of DOE applications; that DOE should encourage and support research activities intended to increase understanding of security technology requirements, and to develop critical components not forthcoming from other sources in a timely manner.
Number Theory and Public-Key Cryptography.
ERIC Educational Resources Information Center
Lefton, Phyllis
1991-01-01
Described are activities in the study of techniques used to conceal the meanings of messages and data. Some background information and two BASIC programs that illustrate the algorithms used in a new cryptographic system called "public-key cryptography" are included. (CW)
Wang, Xiaogang; Zhao, Daomu
2012-05-21
A double-image encryption technique that based on an asymmetric algorithm is proposed. In this method, the encryption process is different from the decryption and the encrypting keys are also different from the decrypting keys. In the nonlinear encryption process, the images are encoded into an amplitude cyphertext, and two phase-only masks (POMs) generated based on phase truncation are kept as keys for decryption. By using the classical double random phase encoding (DRPE) system, the primary images can be collected by an intensity detector that located at the output plane. Three random POMs that applied in the asymmetric encryption can be safely applied as public keys. Simulation results are presented to demonstrate the validity and security of the proposed protocol.
Locating Encrypted Data Hidden Among Non-Encrypted Data Using Statistical Tools
2007-03-01
Encryption algorithm , or Cipher : The encryption scheme consists of a set of encryption transformations and a set of corresponding decryption ... Algorithms Symmetric Key ciphers can be categorized into two specific types. The types differ based on how the encryption / decryption functions perform...keystream (seed) ([MVV97, pg. 21]). The advantage of a stream cipher is two fold. First, the encryption algorithm can be applied
Quantum fully homomorphic encryption scheme based on universal quantum circuit
NASA Astrophysics Data System (ADS)
Liang, Min
2015-08-01
Fully homomorphic encryption enables arbitrary computation on encrypted data without decrypting the data. Here it is studied in the context of quantum information processing. Based on universal quantum circuit, we present a quantum fully homomorphic encryption (QFHE) scheme, which permits arbitrary quantum transformation on any encrypted data. The QFHE scheme is proved to be perfectly secure. In the scheme, the decryption key is different from the encryption key; however, the encryption key cannot be revealed. Moreover, the evaluation algorithm of the scheme is independent of the encryption key, so it is suitable for delegated quantum computing between two parties.
Compressive Optical Image Encryption
Li, Jun; Sheng Li, Jiao; Yang Pan, Yang; Li, Rong
2015-01-01
An optical image encryption technique based on compressive sensing using fully optical means has been proposed. An object image is first encrypted to a white-sense stationary noise pattern using a double random phase encoding (DRPE) method in a Mach-Zehnder interferometer. Then, the encrypted image is highly compressed to a signal using single-pixel compressive holographic imaging in the optical domain. At the receiving terminal, the encrypted image is reconstructed well via compressive sensing theory, and the original image can be decrypted with three reconstructed holograms and the correct keys. The numerical simulations show that the method is effective and suitable for optical image security transmission in future all-optical networks because of the ability of completely optical implementation and substantially smaller hologram data volume. PMID:25992946
Compressive optical image encryption.
Li, Jun; Sheng Li, Jiao; Yang Pan, Yang; Li, Rong
2015-05-20
An optical image encryption technique based on compressive sensing using fully optical means has been proposed. An object image is first encrypted to a white-sense stationary noise pattern using a double random phase encoding (DRPE) method in a Mach-Zehnder interferometer. Then, the encrypted image is highly compressed to a signal using single-pixel compressive holographic imaging in the optical domain. At the receiving terminal, the encrypted image is reconstructed well via compressive sensing theory, and the original image can be decrypted with three reconstructed holograms and the correct keys. The numerical simulations show that the method is effective and suitable for optical image security transmission in future all-optical networks because of the ability of completely optical implementation and substantially smaller hologram data volume.
PEM public key certificate cache server
NASA Astrophysics Data System (ADS)
Cheung, T.
1993-12-01
Privacy Enhanced Mail (PEM) provides privacy enhancement services to users of Internet electronic mail. Confidentiality, authentication, message integrity, and non-repudiation of origin are provided by applying cryptographic measures to messages transferred between end systems by the Message Transfer System. PEM supports both symmetric and asymmetric key distribution. However, the prevalent implementation uses a public key certificate-based strategy, modeled after the X.509 directory authentication framework. This scheme provides an infrastructure compatible with X.509. According to RFC 1422, public key certificates can be stored in directory servers, transmitted via non-secure message exchanges, or distributed via other means. Directory services provide a specialized distributed database for OSI applications. The directory contains information about objects and then provides structured mechanisms for accessing that information. Since directory services are not widely available now, a good approach is to manage certificates in a centralized certificate server. This document describes the detailed design of a centralized certificate cache serve. This server manages a cache of certificates and a cache of Certificate Revocation Lists (CRL's) for PEM applications. PEMapplications contact the server to obtain/store certificates and CRL's. The server software is programmed in C and ELROS. To use this server, ISODE has to be configured and installed properly. The ISODE library 'libisode.a' has to be linked together with this library because ELROS uses the transport layer functions provided by 'libisode.a.' The X.500 DAP library that is included with the ELROS distribution has to be linked in also, since the server uses the DAP library functions to communicate with directory servers.
Low-Power Public Key Cryptography
BEAVER,CHERYL L.; DRAELOS,TIMOTHY J.; HAMILTON,VICTORIA A.; SCHROEPPEL,RICHARD C.; GONZALES,RITA A.; MILLER,RUSSELL D.; THOMAS,EDWARD V.
2000-11-01
This report presents research on public key, digital signature algorithms for cryptographic authentication in low-powered, low-computation environments. We assessed algorithms for suitability based on their signature size, and computation and storage requirements. We evaluated a variety of general purpose and special purpose computing platforms to address issues such as memory, voltage requirements, and special functionality for low-powered applications. In addition, we examined custom design platforms. We found that a custom design offers the most flexibility and can be optimized for specific algorithms. Furthermore, the entire platform can exist on a single Application Specific Integrated Circuit (ASIC) or can be integrated with commercially available components to produce the desired computing platform.
Continuous QKD and high speed data encryption
NASA Astrophysics Data System (ADS)
Zbinden, Hugo; Walenta, Nino; Guinnard, Olivier; Houlmann, Raphael; Wen, Charles Lim Ci; Korzh, Boris; Lunghi, Tommaso; Gisin, Nicolas; Burg, Andreas; Constantin, Jeremy; Legré, Matthieu; Trinkler, Patrick; Caselunghe, Dario; Kulesza, Natalia; Trolliet, Gregory; Vannel, Fabien; Junod, Pascal; Auberson, Olivier; Graf, Yoan; Curchod, Gilles; Habegger, Gilles; Messerli, Etienne; Portmann, Christopher; Henzen, Luca; Keller, Christoph; Pendl, Christian; Mühlberghuber, Michael; Roth, Christoph; Felber, Norbert; Gürkaynak, Frank; Schöni, Daniel; Muheim, Beat
2013-10-01
We present the results of a Swiss project dedicated to the development of high speed quantum key distribution and data encryption. The QKD engine features fully automated key exchange, hardware key distillation based on finite key security analysis, efficient authentication and wavelength division multiplexing of the quantum and the classical channel and one-time pas encryption. The encryption device allows authenticated symmetric key encryption (e.g AES) at rates of up to 100 Gb/s. A new quantum key can uploaded up to 1000 times second from the QKD engine.
Spatial Encryption under Simpler Assumption
NASA Astrophysics Data System (ADS)
Zhou, Muxin; Cao, Zhenfu
Spatial encryption was first proposed by Boneh and Hamburg. They showed that many useful encryption systems can be derived from it. In this paper, we describe two variants of spatial encryption. First we present a scheme that can be proved to be secure under the decisional bilinear Diffie-Hellman assumption, which is much simpler than the BDHE assumption used by Boneh and Hamburg. However, as a compromise, our ciphertext size and private key size are larger. We also discuss some techniques to shrink the private key of this scheme in a real application. Finally, we provide a hybrid construction which allows an optimal tradeoff between efficiency and security.
Privacy-preserving photo sharing based on a public key infrastructure
NASA Astrophysics Data System (ADS)
Yuan, Lin; McNally, David; Küpçü, Alptekin; Ebrahimi, Touradj
2015-09-01
A significant number of pictures are posted to social media sites or exchanged through instant messaging and cloud-based sharing services. Most social media services offer a range of access control mechanisms to protect users privacy. As it is not in the best interest of many such services if their users restrict access to their shared pictures, most services keep users' photos unprotected which makes them available to all insiders. This paper presents an architecture for a privacy-preserving photo sharing based on an image scrambling scheme and a public key infrastructure. A secure JPEG scrambling is applied to protect regional visual information in photos. Protected images are still compatible with JPEG coding and therefore can be viewed by any one on any device. However, only those who are granted secret keys will be able to descramble the photos and view their original versions. The proposed architecture applies an attribute-based encryption along with conventional public key cryptography, to achieve secure transmission of secret keys and a fine-grained control over who may view shared photos. In addition, we demonstrate the practical feasibility of the proposed photo sharing architecture with a prototype mobile application, ProShare, which is built based on iOS platform.
Optically-induced-potential-based image encryption.
Chen, Bing-Chu; Wang, He-Zhou
2011-11-07
We present a technique of nonlinear image encryption by use of virtual optics. The image to be encrypted is superposed on a random intensity image. And this superposed image propagates through a nonlinear medium and a 4-f system with single phase key. The image is encrypted to a stationary white noise. The decryption process is sensitive to the parameters of the encryption system and the phase key in 4-f system. This sensitivity makes attackers hard to access the phase key. In nonlinear medium, optically-induced potentials, which depend on intensity of optical wave, make the superposition principle frustrated. This nonlinearity based on optically induced potentials highly improves the secrecy level of image encryption. Resistance against attacks based on the phase retrieval technique proves that it has the high secrecy level. This nonlinear image encryption based on optically induced potentials is proposed and demonstrated for the first time.
Quantum computing on encrypted data
NASA Astrophysics Data System (ADS)
Fisher, K. A. G.; Broadbent, A.; Shalm, L. K.; Yan, Z.; Lavoie, J.; Prevedel, R.; Jennewein, T.; Resch, K. J.
2014-01-01
The ability to perform computations on encrypted data is a powerful tool for protecting privacy. Recently, protocols to achieve this on classical computing systems have been found. Here, we present an efficient solution to the quantum analogue of this problem that enables arbitrary quantum computations to be carried out on encrypted quantum data. We prove that an untrusted server can implement a universal set of quantum gates on encrypted quantum bits (qubits) without learning any information about the inputs, while the client, knowing the decryption key, can easily decrypt the results of the computation. We experimentally demonstrate, using single photons and linear optics, the encryption and decryption scheme on a set of gates sufficient for arbitrary quantum computations. As our protocol requires few extra resources compared with other schemes it can be easily incorporated into the design of future quantum servers. These results will play a key role in enabling the development of secure distributed quantum systems.
Quantum computing on encrypted data.
Fisher, K A G; Broadbent, A; Shalm, L K; Yan, Z; Lavoie, J; Prevedel, R; Jennewein, T; Resch, K J
2014-01-01
The ability to perform computations on encrypted data is a powerful tool for protecting privacy. Recently, protocols to achieve this on classical computing systems have been found. Here, we present an efficient solution to the quantum analogue of this problem that enables arbitrary quantum computations to be carried out on encrypted quantum data. We prove that an untrusted server can implement a universal set of quantum gates on encrypted quantum bits (qubits) without learning any information about the inputs, while the client, knowing the decryption key, can easily decrypt the results of the computation. We experimentally demonstrate, using single photons and linear optics, the encryption and decryption scheme on a set of gates sufficient for arbitrary quantum computations. As our protocol requires few extra resources compared with other schemes it can be easily incorporated into the design of future quantum servers. These results will play a key role in enabling the development of secure distributed quantum systems.
Proof Checking the RSA (Rivest, Shamir and Adleman) Public Key Encryption Algorithm.
1982-09-01
Fermat’s theorem, number theory , pigeon hole principle. 20. ABSTRACT (Continue an reverse sde it neceeseand Ideify by block nu mbe r) The authors...of integers modulo (p-1)*(q-1). .. Among the lemmas proved mechanically and used in the ma _Aroof are many familia theorems of number theory ...the ring of integers modulo (p-1)*(q-1). Among the lemmas proved mechanically and used in the main proof are many familiar theorems of number theory
Proof Checking the RSA (Rivest, Shamir, and Adleman) Public Key Encryption Algorithm.
1982-09-01
theorem, number theory , pigeon hole principle al20. ABSTRACT (Continue an reverse aide it necessary and Identify by block number) am. We describe the...ring of integers modulo (p-1)*(q-1). Among the lemmas proved mechanically and used in the main proof are many familiar theorems of number theory ...ring of integers modulo (p-1)*(q-1). Among the lemmas proved mechanically and used in the main proof are many familiar theorems of number theory
Dual encryption scheme of images using polarized light.
Alfalou, A; Brosseau, C
2010-07-01
We propose and analyze a dual encryption/decryption scheme, motivated by recent interest in polarization encoding. Compared to standard optical encryption methods, which are based on phase and amplitude manipulation, this encryption procedure relying on Mueller-Stokes formalism provides large flexibility in the key encryption design. The effectiveness of our algorithm is discussed, thanks to a numerical simulation of the polarization encryption/decryption procedure of a 256 gray-level image. Of additional special interest is the immunity of this encryption algorithm to brute force attacks.
Development of a public key infrastructure across multiple enterprises
Sharick, T.M.; Long, J.P.; Desind, B.J.
1997-05-01
Main-stream applications are beginning to incorporate public key cryptography. It can be difficult to deploy this technology without a robust infrastructure to support it. It can also be difficult to deploy a public key infrastructure among multiple enterprises when different applications and standards must be supported. This discussion chronicles the efforts by a team within the US Department of Energy`s Nuclear Weapons Complex to build a public key infrastructure and deploy applications that use it. The emphasis of this talk will be on the lessons learned during this effort and an assessment of the overall impact of this technology.
Wang, Yong; Markman, Adam; Quan, Chenggen; Javidi, Bahram
2016-11-01
We present a photon-counting double-random-phase encryption technique that only requires the photon-limited amplitude of the encrypted image for decryption. The double-random-phase encryption is used to encrypt an image, generating a complex image. Photon counting is applied to the amplitude of the encrypted image, generating a sparse noise-like image; however, the phase information is not retained. By not using the phase information, the encryption process is simplified, allowing for intensity detection and also less information to be recorded. Using a phase numerically generated from the correct encryption keys together with the photon-limited amplitude of the encrypted image, we are able to decrypt the image. Moreover, nonlinear correlation algorithms can be used to authenticate the decrypted image. Both amplitude-based and full-phase encryption using the proposed method are investigated. Preliminary computational results and performance evaluation are presented.
NASA Astrophysics Data System (ADS)
Gunn, Lachlan J.; Chappell, James M.; Allison, Andrew; Abbott, Derek
2014-09-01
While information-theoretic security is often associated with the one-time pad and quantum key distribution, noisy transport media leave room for classical techniques and even covert operation. Transit times across the public internet exhibit a degree of randomness, and cannot be determined noiselessly by an eavesdropper. We demonstrate the use of these measurements for information-theoretically secure communication over the public internet.
Novel Image Encryption based on Quantum Walks
Yang, Yu-Guang; Pan, Qing-Xiang; Sun, Si-Jia; Xu, Peng
2015-01-01
Quantum computation has achieved a tremendous success during the last decades. In this paper, we investigate the potential application of a famous quantum computation model, i.e., quantum walks (QW) in image encryption. It is found that QW can serve as an excellent key generator thanks to its inherent nonlinear chaotic dynamic behavior. Furthermore, we construct a novel QW-based image encryption algorithm. Simulations and performance comparisons show that the proposal is secure enough for image encryption and outperforms prior works. It also opens the door towards introducing quantum computation into image encryption and promotes the convergence between quantum computation and image processing. PMID:25586889
Novel image encryption based on quantum walks.
Yang, Yu-Guang; Pan, Qing-Xiang; Sun, Si-Jia; Xu, Peng
2015-01-14
Quantum computation has achieved a tremendous success during the last decades. In this paper, we investigate the potential application of a famous quantum computation model, i.e., quantum walks (QW) in image encryption. It is found that QW can serve as an excellent key generator thanks to its inherent nonlinear chaotic dynamic behavior. Furthermore, we construct a novel QW-based image encryption algorithm. Simulations and performance comparisons show that the proposal is secure enough for image encryption and outperforms prior works. It also opens the door towards introducing quantum computation into image encryption and promotes the convergence between quantum computation and image processing.
Novel Image Encryption based on Quantum Walks
NASA Astrophysics Data System (ADS)
Yang, Yu-Guang; Pan, Qing-Xiang; Sun, Si-Jia; Xu, Peng
2015-01-01
Quantum computation has achieved a tremendous success during the last decades. In this paper, we investigate the potential application of a famous quantum computation model, i.e., quantum walks (QW) in image encryption. It is found that QW can serve as an excellent key generator thanks to its inherent nonlinear chaotic dynamic behavior. Furthermore, we construct a novel QW-based image encryption algorithm. Simulations and performance comparisons show that the proposal is secure enough for image encryption and outperforms prior works. It also opens the door towards introducing quantum computation into image encryption and promotes the convergence between quantum computation and image processing.
Encryption Devices for Use in a Conditional Access System
NASA Astrophysics Data System (ADS)
Pinder, Howard G.; Palgon, Michael S.
2002-07-01
A cable television system provides conditional access to services. The cable television system includes a headend from which service 'instances', or programs, are broadcast and a plurality of set top units for receiving the instances and selectively decrypting the instances for display to system subscribers. The service instances are encrypted using public and/or private keys provided by service providers or central authorization agents. Keys used by the set tops for selective decryption may also be public or private in nature, and such keys may be reassigned at different times to provide a cable television system in which piracy concerns are minimized.
A Public-Key Based Authentication and Key Establishment Protocol Coupled with a Client Puzzle.
ERIC Educational Resources Information Center
Lee, M. C.; Fung, Chun-Kan
2003-01-01
Discusses network denial-of-service attacks which have become a security threat to the Internet community and suggests the need for reliable authentication protocols in client-server applications. Presents a public-key based authentication and key establishment protocol coupled with a client puzzle protocol and validates it through formal logic…
Information encryption in phase space.
Liu, Jun; Xu, Xiaobin; Wu, Quanying; Sheridan, John T; Situ, Guohai
2015-03-15
In this Letter, we propose an information encryption technique based on the theory of phase-space optics. We show that encoding the plaintext in phase space provides a higher level of security: first, the key-space is significantly enlarged. Second, it is immune to various known-plaintext (cyphertext) attacks to which the double-random phase encryption (DRPE) is vulnerable. Third, the bilinearity of phase-space distributions offers additional security. Theoretical analysis and numerical calculation results show that the proposed technique has significantly different responses to errors added to the cypheretext and the two phase keys in comparison to the classical DRPE.
Optical image encryption via ptychography.
Shi, Yishi; Li, Tuo; Wang, Yali; Gao, Qiankun; Zhang, Sanguo; Li, Haifei
2013-05-01
Ptychography is combined with optical image encryption for the first time. Due to the nature of ptychography, not only is the interferometric optical setup that is usually adopted not required any more, but also the encryption for a complex-valued image is achievable. Considering that the probes overlapping with each other is the crucial factor in ptychography, their complex-amplitude functions can serve as a kind of secret keys that lead to the enlarged key space and the enhanced system security. Further, since only introducing the probes into the input of common system is required, it is convenient to combine ptychography with many existing optical image encryption systems for varied security applications.
Dunigan, T.; Cao, C.
1997-08-01
This report describes an architecture and implementation for doing group key management over a data communications network. The architecture describes a protocol for establishing a shared encryption key among an authenticated and authorized collection of network entities. Group access requires one or more authorization certificates. The implementation includes a simple public key and certificate infrastructure. Multicast is used for some of the key management messages. An application programming interface multiplexes key management and user application messages. An implementation using the new IP security protocols is postulated. The architecture is compared with other group key management proposals, and the performance and the limitations of the implementation are described.
An investigation of DUA caching strategies for public key certificates
Cheung, T.C.
1993-11-01
Internet Privacy Enhanced Mail (PEM) provides security services to users of Internet electronic mail. PEM is designed with the intention that it will eventually obtain public key certificates from the X.500 directory service. However, such a capability is not present in most PEM implementations today. While the prevalent PEM implementation uses a public key certificate-based strategy, certificates are mostly distributed via e-mail exchanges, which raises several security and performance issues. In this thesis research, we changed the reference PEM implementation to make use of the X.500 directory service instead of local databases for public key certificate management. The thesis discusses some problems with using the X.500 directory service, explores the relevant issues, and develops an approach to address them. The approach makes use of a memory cache to store public key certificates. We implemented a centralized cache server and addressed the denial-of-service security problem that is present in the server. In designing the cache, we investigated several cache management strategies. One result of our study is that the use of a cache significantly improves performance. Our research also indicates that security incurs extra performance cost. Different cache replacement algorithms do not seem to yield significant performance differences, while delaying dirty-writes to the backing store does improve performance over immediate writes.
Public Expenditures on Children through 2008: Key Facts
ERIC Educational Resources Information Center
Macomber, Jennifer; Isaacs, Julia; Kent, Adam; Vericker, Tracy
2010-01-01
This report provides the key findings on the public spending on children through 2008. They are: (1) Spending on children increased under the American Recovery and Reinvestment Act (ARRA) and other stimulus spending, but not proportionately to other federal spending. As ARRA expires, we project that spending on children will decline, assuming no…
Child protection reports: key issues arising for public health nurses.
Hanafin, Sinead
2013-10-01
Similar to other countries, there have been a number of high-profile reports into past and recent cases of child abuse and neglect in Ireland. The most recent of these have been the Monageer Inquiry, the Ryan Report, the Roscommon Child Care Case and the Report of the Independent Child Death Review Group. An analysis of these reports highlights the critical role played by public health nurses with troubled families. It also makes explicit key issues that consistently emerge as problematic in terms of professional practice. This paper summarises the main findings of the reports as they relate to the public health nursing service and identifies key themes emerging along with recommendations arising. The emerging themes relate to assessment, early intervention, record keeping, communication and interdisciplinary working and the role of public health nursing management.
An efficient and provable secure revocable identity-based encryption scheme.
Wang, Changji; Li, Yuan; Xia, Xiaonan; Zheng, Kangjia
2014-01-01
Revocation functionality is necessary and crucial to identity-based cryptosystems. Revocable identity-based encryption (RIBE) has attracted a lot of attention in recent years, many RIBE schemes have been proposed in the literature but shown to be either insecure or inefficient. In this paper, we propose a new scalable RIBE scheme with decryption key exposure resilience by combining Lewko and Waters' identity-based encryption scheme and complete subtree method, and prove our RIBE scheme to be semantically secure using dual system encryption methodology. Compared to existing scalable and semantically secure RIBE schemes, our proposed RIBE scheme is more efficient in term of ciphertext size, public parameters size and decryption cost at price of a little looser security reduction. To the best of our knowledge, this is the first construction of scalable and semantically secure RIBE scheme with constant size public system parameters.
An Efficient and Provable Secure Revocable Identity-Based Encryption Scheme
Wang, Changji; Li, Yuan; Xia, Xiaonan; Zheng, Kangjia
2014-01-01
Revocation functionality is necessary and crucial to identity-based cryptosystems. Revocable identity-based encryption (RIBE) has attracted a lot of attention in recent years, many RIBE schemes have been proposed in the literature but shown to be either insecure or inefficient. In this paper, we propose a new scalable RIBE scheme with decryption key exposure resilience by combining Lewko and Waters’ identity-based encryption scheme and complete subtree method, and prove our RIBE scheme to be semantically secure using dual system encryption methodology. Compared to existing scalable and semantically secure RIBE schemes, our proposed RIBE scheme is more efficient in term of ciphertext size, public parameters size and decryption cost at price of a little looser security reduction. To the best of our knowledge, this is the first construction of scalable and semantically secure RIBE scheme with constant size public system parameters. PMID:25238418
Fault Analysis-based Logic Encryption (Preprint)
2013-11-01
work on logic encryption. Section 8 concludes the paper . 2. METRIC FOR LOGIC ENCRYPTION The defender (designer) has to prevent his IP from being...publication of this paper . This material is based on work fund- ed by AFRL under contract No. FA8750-11-2-0274. Received and cleared for public release by...USENIX Se- curity, pp. 291-306, 2007. [4] Defense Science Board (DSB) study on High Performance Microchip Supply. [Online]. http://www.aoq.osd.mil
High-Speed Quantum Key Distribution Systems for Optical Fiber Networks in Campus and Metro Areas
2008-01-01
encryption and decryption of streaming video. Proc. of SPIE Vol. 7092 70920I-12 VI!Ce IU{GLUGf Ob{!C91 E!PGL Ob{!CI E!P eL p S ObI!C2 EI6CLOU! .1 D 2flLAe...Bob node is encrypted using the one-time pad cipher with the secure keys and sent to Alice over an unsecured public network, which, in this...than be used to encrypt and decrypt messages. Existing security protocols, such as IPsec and TLS, currently rely on public key exchange methods to
An application of different dioids in public key cryptography
Durcheva, Mariana I.
2014-11-18
Dioids provide a natural framework for analyzing a broad class of discrete event dynamical systems such as the design and analysis of bus and railway timetables, scheduling of high-throughput industrial processes, solution of combinatorial optimization problems, the analysis and improvement of flow systems in communication networks. They have appeared in several branches of mathematics such as functional analysis, optimization, stochastic systems and dynamic programming, tropical geometry, fuzzy logic. In this paper we show how to involve dioids in public key cryptography. The main goal is to create key – exchange protocols based on dioids. Additionally the digital signature scheme is presented.
Key-phrase based classification of public health web pages.
Dolamic, Ljiljana; Boyer, Célia
2013-01-01
This paper describes and evaluates the public health web pages classification model based on key phrase extraction and matching. Easily extendible both in terms of new classes as well as the new language this method proves to be a good solution for text classification faced with the total lack of training data. To evaluate the proposed solution we have used a small collection of public health related web pages created by a double blind manual classification. Our experiments have shown that by choosing the adequate threshold value the desired value for either precision or recall can be achieved.
Optical double-image encryption and authentication by sparse representation.
Mohammed, Emad A; Saadon, H L
2016-12-10
An optical double-image encryption and authentication method by sparse representation is proposed. The information from double-image encryption can be integrated into a sparse representation. Unlike the traditional double-image encryption technique, only sparse (partial) data from the encrypted data is adopted for the authentication process. Simulation results demonstrate that the correct authentication results are achieved even with partial information from the encrypted data. The randomly selected sparse encrypted information will be used as an effective key for a security system. Therefore, the proposed method is feasible, effective, and can provide an additional security layer for optical security systems. In addition, the method also achieved the general requirements of storage and transmission due to a high reduction of the encrypted information.
A Survey of Research Progress and Development Tendency of Attribute-Based Encryption
Pang, Liaojun; Yang, Jie; Jiang, Zhengtao
2014-01-01
With the development of cryptography, the attribute-based encryption (ABE) draws widespread attention of the researchers in recent years. The ABE scheme, which belongs to the public key encryption mechanism, takes attributes as public key and associates them with the ciphertext or the user's secret key. It is an efficient way to solve open problems in access control scenarios, for example, how to provide data confidentiality and expressive access control at the same time. In this paper, we survey the basic ABE scheme and its two variants: the key-policy ABE (KP-ABE) scheme and the ciphertext-policy ABE (CP-ABE) scheme. We also pay attention to other researches relating to the ABE schemes, including multiauthority, user/attribute revocation, accountability, and proxy reencryption, with an extensive comparison of their functionality and performance. Finally, possible future works and some conclusions are pointed out. PMID:25101313
EEG based image encryption via quantum walks.
Rawat, N; Shin, Y; Balasingham, I
2016-08-01
An electroencephalogram (EEG) based image encryption combined with Quantum walks (QW) is encoded in Fresnel domain. The computational version of EEG randomizes the original plaintext whereas QW can serve as an excellent key generator due to its inherent nonlinear chaotic dynamic behavior. First, a spatially coherent monochromatic laser beam passes through an SLM, which introduces an arbitrary EEG phase-only mask. The modified beam is collected by a CCD. Further, the intensity is multiply with the QW digitally. EEG shows high sensitivity to system parameters and capable of encrypting and transmitting the data whereas QW has unpredictability, stability and non-periodicity. Only applying the correct keys, the original image can be retrieved successfully. Simulations and comparisons show the proposed method to be secure enough for image encryption and outperforms prior works. The proposed method opens the door towards introducing EEG and quantum computation into image encryption and promotes the convergence between our approach and image processing.
Report on the Development of the Advanced Encryption Standard (AES)
Nechvatal, James; Barker, Elaine; Bassham, Lawrence; Burr, William; Dworkin, Morris; Foti, James; Roback, Edward
2001-01-01
In 1997, the National Institute of Standards and Technology (NIST) initiated a process to select a symmetric-key encryption algorithm to be used to protect sensitive (unclassified) Federal information in furtherance of NIST’s statutory responsibilities. In 1998, NIST announced the acceptance of 15 candidate algorithms and requested the assistance of the cryptographic research community in analyzing the candidates. This analysis included an initial examination of the security and efficiency characteristics for each algorithm. NIST reviewed the results of this preliminary research and selected MARS, RC™, Rijndael, Serpent and Twofish as finalists. Having reviewed further public analysis of the finalists, NIST has decided to propose Rijndael as the Advanced Encryption Standard (AES). The research results and rationale for this selection are documented in this report. PMID:27500035
QR code optical encryption using spatially incoherent illumination
NASA Astrophysics Data System (ADS)
Cheremkhin, P. A.; Krasnov, V. V.; Rodin, V. G.; Starikov, R. S.
2017-02-01
Optical encryption is an actively developing field of science. The majority of encryption techniques use coherent illumination and suffer from speckle noise, which severely limits their applicability. The spatially incoherent encryption technique does not have this drawback, but its effectiveness is dependent on the Fourier spectrum properties of the image to be encrypted. The application of a quick response (QR) code in the capacity of a data container solves this problem, and the embedded error correction code also enables errorless decryption. The optical encryption of digital information in the form of QR codes using spatially incoherent illumination was implemented experimentally. The encryption is based on the optical convolution of the image to be encrypted with the kinoform point spread function, which serves as an encryption key. Two liquid crystal spatial light modulators were used in the experimental setup for the QR code and the kinoform imaging, respectively. The quality of the encryption and decryption was analyzed in relation to the QR code size. Decryption was conducted digitally. The successful decryption of encrypted QR codes of up to 129 × 129 pixels was demonstrated. A comparison with the coherent QR code encryption technique showed that the proposed technique has a signal-to-noise ratio that is at least two times higher.
Optical design of cipher block chaining (CBC) encryption mode by using digital holography
NASA Astrophysics Data System (ADS)
Gil, Sang Keun; Jeon, Seok Hee; Jung, Jong Rae; Kim, Nam
2016-03-01
We propose an optical design of cipher block chaining (CBC) encryption by using digital holographic technique, which has higher security than the conventional electronic method because of the analog-type randomized cipher text with 2-D array. In this paper, an optical design of CBC encryption mode is implemented by 2-step quadrature phase-shifting digital holographic encryption technique using orthogonal polarization. A block of plain text is encrypted with the encryption key by applying 2-step phase-shifting digital holography, and it is changed into cipher text blocks which are digital holograms. These ciphered digital holograms with the encrypted information are Fourier transform holograms and are recorded on CCDs with 256 gray levels quantized intensities. The decryption is computed by these encrypted digital holograms of cipher texts, the same encryption key and the previous cipher text. Results of computer simulations are presented to verify that the proposed method shows the feasibility in the high secure CBC encryption system.
Investigating Quantum Data Encrypted Modulation States
2014-11-01
loss, detector quantum efficiency , amplifier gain, and noise sources over and above photon shot noise. The signal and Local Oscillator are two...INVESTIGATING QUANTUM DATA ENCRYPTED MODULATION STATES NOVEMBER 2014 INTERIM TECHNICAL REPORT APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED...OCT 2013 – OCT 2014 4. TITLE AND SUBTITLE INVESTIGATING QUANTUM DATA ENCRYPTED MODULATION STATES 5a. CONTRACT NUMBER IN-HOUSE / R148 5b. GRANT
Multiply-agile encryption in high speed communication networks
Pierson, L.G.; Witzke, E.L.
1997-05-01
Different applications have different security requirements for data privacy, data integrity, and authentication. Encryption is one technique that addresses these requirements. Encryption hardware, designed for use in high-speed communications networks, can satisfy a wide variety of security requirements if that hardware is key-agile, robustness-agile and algorithm-agile. Hence, multiply-agile encryption provides enhanced solutions to the secrecy, interoperability and quality of service issues in high-speed networks. This paper defines these three types of agile encryption. Next, implementation issues are discussed. While single-algorithm, key-agile encryptors exist, robustness-agile and algorithm-agile encryptors are still research topics.
Symmetric quantum fully homomorphic encryption with perfect security
NASA Astrophysics Data System (ADS)
Liang, Min
2013-12-01
Suppose some data have been encrypted, can you compute with the data without decrypting them? This problem has been studied as homomorphic encryption and blind computing. We consider this problem in the context of quantum information processing, and present the definitions of quantum homomorphic encryption (QHE) and quantum fully homomorphic encryption (QFHE). Then, based on quantum one-time pad (QOTP), we construct a symmetric QFHE scheme, where the evaluate algorithm depends on the secret key. This scheme permits any unitary transformation on any -qubit state that has been encrypted. Compared with classical homomorphic encryption, the QFHE scheme has perfect security. Finally, we also construct a QOTP-based symmetric QHE scheme, where the evaluate algorithm is independent of the secret key.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-19
... From the Federal Register Online via the Government Publishing Office GENERAL SERVICES ADMINISTRATION Public Buildings Service; Key Largo Beacon Annex Site; Key Largo, FL; Transfer of Property..., identified as Key Largo Beacon Annex Site, Key Largo, FL to the U.S. Fish and Wildlife Service, Department...
A quantum approach to homomorphic encryption
Tan, Si-Hui; Kettlewell, Joshua A.; Ouyang, Yingkai; Chen, Lin; Fitzsimons, Joseph F.
2016-01-01
Encryption schemes often derive their power from the properties of the underlying algebra on the symbols used. Inspired by group theoretic tools, we use the centralizer of a subgroup of operations to present a private-key quantum homomorphic encryption scheme that enables a broad class of quantum computation on encrypted data. The quantum data is encoded on bosons of distinct species in distinct spatial modes, and the quantum computations are manipulations of these bosons in a manner independent of their species. A particular instance of our encoding hides up to a constant fraction of the information encrypted. This fraction can be made arbitrarily close to unity with overhead scaling only polynomially in the message length. This highlights the potential of our protocol to hide a non-trivial amount of information, and is suggestive of a large class of encodings that might yield better security. PMID:27658349
A quantum approach to homomorphic encryption
NASA Astrophysics Data System (ADS)
Tan, Si-Hui; Kettlewell, Joshua A.; Ouyang, Yingkai; Chen, Lin; Fitzsimons, Joseph F.
2016-09-01
Encryption schemes often derive their power from the properties of the underlying algebra on the symbols used. Inspired by group theoretic tools, we use the centralizer of a subgroup of operations to present a private-key quantum homomorphic encryption scheme that enables a broad class of quantum computation on encrypted data. The quantum data is encoded on bosons of distinct species in distinct spatial modes, and the quantum computations are manipulations of these bosons in a manner independent of their species. A particular instance of our encoding hides up to a constant fraction of the information encrypted. This fraction can be made arbitrarily close to unity with overhead scaling only polynomially in the message length. This highlights the potential of our protocol to hide a non-trivial amount of information, and is suggestive of a large class of encodings that might yield better security.
A quantum approach to homomorphic encryption.
Tan, Si-Hui; Kettlewell, Joshua A; Ouyang, Yingkai; Chen, Lin; Fitzsimons, Joseph F
2016-09-23
Encryption schemes often derive their power from the properties of the underlying algebra on the symbols used. Inspired by group theoretic tools, we use the centralizer of a subgroup of operations to present a private-key quantum homomorphic encryption scheme that enables a broad class of quantum computation on encrypted data. The quantum data is encoded on bosons of distinct species in distinct spatial modes, and the quantum computations are manipulations of these bosons in a manner independent of their species. A particular instance of our encoding hides up to a constant fraction of the information encrypted. This fraction can be made arbitrarily close to unity with overhead scaling only polynomially in the message length. This highlights the potential of our protocol to hide a non-trivial amount of information, and is suggestive of a large class of encodings that might yield better security.
Voltage Identify Based Encryption (VIBE)
2005-03-01
PUBLIC RELEASE; DISTRIBUTION UNLIMITED. 13. ABSTRACT (Maximum 200 Words) Invented by Dr. Dan Boneh and Dr. Matt Franklin in 2001, Identity-Based...20 Introduction Invented by Dr. Dan Boneh and Dr. Matt Franklin in 2001, Identity-Based Encryption or IBE, is a breakthrough in...the effectiveness of the technology developed to implement the Boneh -Franklin IBE. This contract provided for the necessary hardware and software
Dynamic video encryption algorithm for H.264/AVC based on a spatiotemporal chaos system.
Xu, Hui; Tong, Xiao-Jun; Zhang, Miao; Wang, Zhu; Li, Ling-Hao
2016-06-01
Video encryption schemes mostly employ the selective encryption method to encrypt parts of important and sensitive video information, aiming to ensure the real-time performance and encryption efficiency. The classic block cipher is not applicable to video encryption due to the high computational overhead. In this paper, we propose the encryption selection control module to encrypt video syntax elements dynamically which is controlled by the chaotic pseudorandom sequence. A novel spatiotemporal chaos system and binarization method is used to generate a key stream for encrypting the chosen syntax elements. The proposed scheme enhances the resistance against attacks through the dynamic encryption process and high-security stream cipher. Experimental results show that the proposed method exhibits high security and high efficiency with little effect on the compression ratio and time cost.
The role of decimated sequences in scaling encryption speeds through parallelism
Witzke, E.L.
1995-09-01
Encryption performance, in terms of bits per second encrypted, has not scaled well as network performance has increased. The authors felt that multiple encryption modules operating in parallel would be the cornerstone of scalable encryption. One major problem with parallelizing encryption is ensuring that each encryption module is getting the proper portion of the key sequence at the correct point in the encryption or decryption of the message. Many encryption schemes use linear recurring sequences, which may be generated by a linear feedback shift register. Instead of using a linear feedback shift register, the authors describe a method to generate the linear recurring sequence by using parallel decimated sequences, one per encryption module. Computing decimated sequences can be time consuming, so the authors have also described a way to compute these sequences with logic gates rather than arithmetic operations.
Attribute-based proxy re-encryption with keyword search.
Shi, Yanfeng; Liu, Jiqiang; Han, Zhen; Zheng, Qingji; Zhang, Rui; Qiu, Shuo
2014-01-01
Keyword search on encrypted data allows one to issue the search token and conduct search operations on encrypted data while still preserving keyword privacy. In the present paper, we consider the keyword search problem further and introduce a novel notion called attribute-based proxy re-encryption with keyword search (ABRKS), which introduces a promising feature: In addition to supporting keyword search on encrypted data, it enables data owners to delegate the keyword search capability to some other data users complying with the specific access control policy. To be specific, ABRKS allows (i) the data owner to outsource his encrypted data to the cloud and then ask the cloud to conduct keyword search on outsourced encrypted data with the given search token, and (ii) the data owner to delegate other data users keyword search capability in the fine-grained access control manner through allowing the cloud to re-encrypted stored encrypted data with a re-encrypted data (embedding with some form of access control policy). We formalize the syntax and security definitions for ABRKS, and propose two concrete constructions for ABRKS: key-policy ABRKS and ciphertext-policy ABRKS. In the nutshell, our constructions can be treated as the integration of technologies in the fields of attribute-based cryptography and proxy re-encryption cryptography.
Attribute-Based Proxy Re-Encryption with Keyword Search
Shi, Yanfeng; Liu, Jiqiang; Han, Zhen; Zheng, Qingji; Zhang, Rui; Qiu, Shuo
2014-01-01
Keyword search on encrypted data allows one to issue the search token and conduct search operations on encrypted data while still preserving keyword privacy. In the present paper, we consider the keyword search problem further and introduce a novel notion called attribute-based proxy re-encryption with keyword search (), which introduces a promising feature: In addition to supporting keyword search on encrypted data, it enables data owners to delegate the keyword search capability to some other data users complying with the specific access control policy. To be specific, allows (i) the data owner to outsource his encrypted data to the cloud and then ask the cloud to conduct keyword search on outsourced encrypted data with the given search token, and (ii) the data owner to delegate other data users keyword search capability in the fine-grained access control manner through allowing the cloud to re-encrypted stored encrypted data with a re-encrypted data (embedding with some form of access control policy). We formalize the syntax and security definitions for , and propose two concrete constructions for : key-policy and ciphertext-policy . In the nutshell, our constructions can be treated as the integration of technologies in the fields of attribute-based cryptography and proxy re-encryption cryptography. PMID:25549257
Three-dimensional information encryption and anticounterfeiting using digital holography.
Shiu, Min-Tzung; Chew, Yang-Kun; Chan, Huang-Tian; Wong, Xin-Yu; Chang, Chi-Ching
2015-01-01
In this work, arbitrary micro phase-step digital holography with optical interferometry and digital image processing is utilized to obtain information about an image of a three-dimensional object and encrypting keys. Then, a computer-generated hologram is used for the purpose of holographic encryption. All information about the keys is required to perform the decryption, comprising the amplitude and phase distribution of the encrypting key, the distance of image reconstruction, zero-order term elimination, and twin-image term suppression. In addition to using identifiable information on different image planes and linear superposition processing hidden within the encrypted information, not only can we convey an important message, but we can also achieve anticounterfeiting. This approach retains the strictness of traditional holographic encryption and the convenience of digital holographic processing without image distortion. Therefore, this method provides better solutions to earlier methods for the security of the transmission of holographic information.
Single-random-phase holographic encryption of images
NASA Astrophysics Data System (ADS)
Tsang, P. W. M.
2017-02-01
In this paper, a method is proposed for encrypting an optical image onto a phase-only hologram, utilizing a single random phase mask as the private encryption key. The encryption process can be divided into 3 stages. First the source image to be encrypted is scaled in size, and pasted onto an arbitrary position in a larger global image. The remaining areas of the global image that are not occupied by the source image could be filled with randomly generated contents. As such, the global image as a whole is very different from the source image, but at the same time the visual quality of the source image is preserved. Second, a digital Fresnel hologram is generated from the new image, and converted into a phase-only hologram based on bi-directional error diffusion. In the final stage, a fixed random phase mask is added to the phase-only hologram as the private encryption key. In the decryption process, the global image together with the source image it contained, can be reconstructed from the phase-only hologram if it is overlaid with the correct decryption key. The proposed method is highly resistant to different forms of Plain-Text-Attacks, which are commonly used to deduce the encryption key in existing holographic encryption process. In addition, both the encryption and the decryption processes are simple and easy to implement.
Shao, Zhuhong; Shu, Huazhong; Wu, Jiasong; Dong, Zhifang; Coatrieux, Gouenou; Coatrieux, Jean Louis
2014-03-10
This paper describes a novel algorithm to encrypt double color images into a single undistinguishable image in quaternion gyrator domain. By using an iterative phase retrieval algorithm, the phase masks used for encryption are obtained. Subsequently, the encrypted image is generated via cascaded quaternion gyrator transforms with different rotation angles. The parameters in quaternion gyrator transforms and phases serve as encryption keys. By knowing these keys, the original color images can be fully restituted. Numerical simulations have demonstrated the validity of the proposed encryption system as well as its robustness against loss of data and additive Gaussian noise.
Quantum Image Encryption Algorithm Based on Quantum Image XOR Operations
NASA Astrophysics Data System (ADS)
Gong, Li-Hua; He, Xiang-Tao; Cheng, Shan; Hua, Tian-Xiang; Zhou, Nan-Run
2016-07-01
A novel encryption algorithm for quantum images based on quantum image XOR operations is designed. The quantum image XOR operations are designed by using the hyper-chaotic sequences generated with the Chen's hyper-chaotic system to control the control-NOT operation, which is used to encode gray-level information. The initial conditions of the Chen's hyper-chaotic system are the keys, which guarantee the security of the proposed quantum image encryption algorithm. Numerical simulations and theoretical analyses demonstrate that the proposed quantum image encryption algorithm has larger key space, higher key sensitivity, stronger resistance of statistical analysis and lower computational complexity than its classical counterparts.
Optimal Symmetric Ternary Quantum Encryption Schemes
NASA Astrophysics Data System (ADS)
Wang, Yu-qi; She, Kun; Huang, Ru-fen; Ouyang, Zhong
2016-11-01
In this paper, we present two definitions of the orthogonality and orthogonal rate of an encryption operator, and we provide a verification process for the former. Then, four improved ternary quantum encryption schemes are constructed. Compared with Scheme 1 (see Section 2.3), these four schemes demonstrate significant improvements in term of calculation and execution efficiency. Especially, under the premise of the orthogonal rate ɛ as secure parameter, Scheme 3 (see Section 4.1) shows the highest level of security among them. Through custom interpolation functions, the ternary secret key source, which is composed of the digits 0, 1 and 2, is constructed. Finally, we discuss the security of both the ternary encryption operator and the secret key source, and both of them show a high level of security and high performance in execution efficiency.
Investigating Encrypted Material
NASA Astrophysics Data System (ADS)
McGrath, Niall; Gladyshev, Pavel; Kechadi, Tahar; Carthy, Joe
When encrypted material is discovered during a digital investigation and the investigator cannot decrypt the material then s/he is faced with the problem of how to determine the evidential value of the material. This research is proposing a methodology of extracting probative value from the encrypted file of a hybrid cryptosystem. The methodology also incorporates a technique for locating the original plaintext file. Since child pornography (KP) images and terrorist related information (TI) are transmitted in encrypted format the digital investigator must ask the question Cui Bono? - who benefits or who is the recipient? By doing this the scope of the digital investigation can be extended to reveal the intended recipient.
Sandia Scalable Encryption Software
Tarman, Thomas D.
1997-08-13
Sandia Scalable Encryption Library (SSEL) Version 1.0 is a library of functions that implement Sandia''s scalable encryption algorithm. This algorithm is used to encrypt Asynchronous Transfer Mode (ATM) data traffic, and is capable of operating on an arbitrary number of bits at a time (which permits scaling via parallel implementations), while being interoperable with differently scaled versions of this algorithm. The routines in this library implement 8 bit and 32 bit versions of a non-linear mixer which is compatible with Sandia''s hardware-based ATM encryptor.
Chaos-Based Simultaneous Compression and Encryption for Hadoop.
Usama, Muhammad; Zakaria, Nordin
2017-01-01
Data compression and encryption are key components of commonly deployed platforms such as Hadoop. Numerous data compression and encryption tools are presently available on such platforms and the tools are characteristically applied in sequence, i.e., compression followed by encryption or encryption followed by compression. This paper focuses on the open-source Hadoop framework and proposes a data storage method that efficiently couples data compression with encryption. A simultaneous compression and encryption scheme is introduced that addresses an important implementation issue of source coding based on Tent Map and Piece-wise Linear Chaotic Map (PWLM), which is the infinite precision of real numbers that result from their long products. The approach proposed here solves the implementation issue by removing fractional components that are generated by the long products of real numbers. Moreover, it incorporates a stealth key that performs a cyclic shift in PWLM without compromising compression capabilities. In addition, the proposed approach implements a masking pseudorandom keystream that enhances encryption quality. The proposed algorithm demonstrated a congruent fit within the Hadoop framework, providing robust encryption security and compression.
Chaos-Based Simultaneous Compression and Encryption for Hadoop
Zakaria, Nordin
2017-01-01
Data compression and encryption are key components of commonly deployed platforms such as Hadoop. Numerous data compression and encryption tools are presently available on such platforms and the tools are characteristically applied in sequence, i.e., compression followed by encryption or encryption followed by compression. This paper focuses on the open-source Hadoop framework and proposes a data storage method that efficiently couples data compression with encryption. A simultaneous compression and encryption scheme is introduced that addresses an important implementation issue of source coding based on Tent Map and Piece-wise Linear Chaotic Map (PWLM), which is the infinite precision of real numbers that result from their long products. The approach proposed here solves the implementation issue by removing fractional components that are generated by the long products of real numbers. Moreover, it incorporates a stealth key that performs a cyclic shift in PWLM without compromising compression capabilities. In addition, the proposed approach implements a masking pseudorandom keystream that enhances encryption quality. The proposed algorithm demonstrated a congruent fit within the Hadoop framework, providing robust encryption security and compression. PMID:28072850
Argumentation Key to Communicating Climate Change to the Public
NASA Astrophysics Data System (ADS)
Bleicher, R. E.; Lambert, J. L.
2012-12-01
Argumentation plays an important role in how we communicate climate change science to the public and is a key component integrated throughout the Next Generation Science Standards. A scientific argument can be described as a disagreement between explanations with data being used to justify each position. Argumentation is social process where two or more individuals construct and critique arguments (Kuhn & Udell, 2003; Nussbaum, 1997). Sampson, Grooms, and Walker's (2011) developed a framework for understanding the components of a scientific argument. The three components start with a claim (a conjecture, conclusion, explanation, or an answer to a research question). This claim must fit the evidence (observations that show trends over time, relationships between variables or difference between groups). The evidence must be justified with reasoning (explains how the evidence supports the explanation and whey it should count as support). In a scientific argument, or debate, the controversy focuses on how data were collected, what data can or should be included, and what inferences can be made based on a set of evidence. Toulmin's model (1969) also includes rebutting or presenting an alternative explanation supported by counter evidence and reasoning of why the alternative is not the appropriate explanation for the question of the problem. The process of scientific argumentation should involve the construction and critique of scientific arguments, one that involves the consideration of alternative hypotheses (Lawson, 2003). Scientific literacy depends as much on the ability to refute and recognize poor scientific arguments as much as it does on the ability to present an effective argument based on good scientific data (Osborne, 2010). Argument is, therefore, a core feature of science. When students learn to construct a sound scientific argument, they demonstrate critical thinking and a mastery of the science being taught. To present a convincing argument in support of
Verifiable Quantum Encryption and its Practical Applications
NASA Astrophysics Data System (ADS)
Shi, Run-hua
2016-12-01
In this paper, we present a novel verifiable quantum encryption scheme, in which a sender encrypts a classical plaintext into a quantum ciphertext, such that only a specified receiver can decrypt the ciphertext and further get the plaintext. This scheme can not only ensure the unconditional security of the plaintext, but can also verify the validness of the plaintext. In addition, we consider its practical applications with key reuse and further present a practical application protocol for secure two-party quantum scalar product.
Verifiable Quantum Encryption and its Practical Applications
NASA Astrophysics Data System (ADS)
Shi, Run-hua
2017-04-01
In this paper, we present a novel verifiable quantum encryption scheme, in which a sender encrypts a classical plaintext into a quantum ciphertext, such that only a specified receiver can decrypt the ciphertext and further get the plaintext. This scheme can not only ensure the unconditional security of the plaintext, but can also verify the validness of the plaintext. In addition, we consider its practical applications with key reuse and further present a practical application protocol for secure two-party quantum scalar product.
A Novel Image Encryption Algorithm Based on DNA Subsequence Operation
Zhang, Qiang; Xue, Xianglian; Wei, Xiaopeng
2012-01-01
We present a novel image encryption algorithm based on DNA subsequence operation. Different from the traditional DNA encryption methods, our algorithm does not use complex biological operation but just uses the idea of DNA subsequence operations (such as elongation operation, truncation operation, deletion operation, etc.) combining with the logistic chaotic map to scramble the location and the value of pixel points from the image. The experimental results and security analysis show that the proposed algorithm is easy to be implemented, can get good encryption effect, has a wide secret key's space, strong sensitivity to secret key, and has the abilities of resisting exhaustive attack and statistic attack. PMID:23093912
A DRM based on renewable broadcast encryption
NASA Astrophysics Data System (ADS)
Ramkumar, Mahalingam; Memon, Nasir
2005-07-01
We propose an architecture for digital rights management based on a renewable, random key pre-distribution (KPD) scheme, HARPS (hashed random preloaded subsets). The proposed architecture caters for broadcast encryption by a trusted authority (TA) and by "parent" devices (devices used by vendors who manufacture compliant devices) for periodic revocation of devices. The KPD also facilitates broadcast encryption by peer devices, which permits peers to distribute content, and efficiently control access to the content encryption secret using subscription secrets. The underlying KPD also caters for broadcast authentication and mutual authentication of any two devices, irrespective of the vendors manufacturing the device, and thus provides a comprehensive solution for securing interactions between devices taking part in a DRM system.
Image encryption using eight dimensional chaotic cat map
NASA Astrophysics Data System (ADS)
Ganesan, K.; Murali, K.
2014-06-01
In recent years, a large number of discrete chaotic cryptographic algorithms have been proposed. However, most of them encounter some problems such as lack of robustness and security. In this paper, we introduce a new image encryption algorithm based on eight-dimensional (nonlinear) chaotic cat map. Encryption of image is different from that of texts due to some intrinsic features of image such as bulk data capacity and high redundancy, which are generally difficult to handle by traditional methods. In traditional methods the key space is small and the security is weak. The proposed algorithm tries to address these problems and also tries to enhance the encryption speed. In this paper an eight dimensional chaotic cat map is used to encrypt the intensity values of pixels using lookup table method thereby significantly increasing the speed and security of encryption. The proposed algorithm is found to be resistive against chosen/known-plaintext attacks, statistical and differential attacks.
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.
Lin, Chao; Shen, Xueju; Li, Baochen
2014-08-25
We demonstrate that all parameters of optical lightwave can be simultaneously designed as keys in security system. This multi-dimensional property of key can significantly enlarge the key space and further enhance the security level of the system. The single-shot off-axis digital holography with orthogonal polarized reference waves is employed to perform polarization state recording on object wave. Two pieces of polarization holograms are calculated and fabricated to be arranged in reference arms to generate random amplitude and phase distribution respectively. When reconstruction, original information which is represented with QR code can be retrieved using Fresnel diffraction with decryption keys and read out noise-free. Numerical simulation results for this cryptosystem are presented. An analysis on the key sensitivity and fault tolerance properties are also provided.
On the security of a simple three-party key exchange protocol without server's public keys.
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.
Encryption and the loss of patient data.
Miller, Amalia R; Tucker, Catherine E
2011-01-01
Fast-paced IT advances have made it increasingly possible and useful for firms to collect data on their customers on an unprecedented scale. One downside of this is that firms can experience negative publicity and financial damage if their data are breached. This is particularly the case in the medical sector, where we find empirical evidence that increased digitization of patient data is associated with more data breaches. The encryption of customer data is often presented as a potential solution, because encryption acts as a disincentive for potential malicious hackers, and can minimize the risk of breached data being put to malicious use. However, encryption both requires careful data management policies to be successful and does not ward off the insider threat. Indeed, we find no empirical evidence of a decrease in publicized instances of data loss associated with the use of encryption. Instead, there are actually increases in the cases of publicized data loss due to internal fraud or loss of computer equipment.
Secure key storage and distribution
Agrawal, Punit
2015-06-02
This disclosure describes a distributed, fault-tolerant security system that enables the secure storage and distribution of private keys. In one implementation, the security system includes a plurality of computing resources that independently store private keys provided by publishers and encrypted using a single security system public key. To protect against malicious activity, the security system private key necessary to decrypt the publication private keys is not stored at any of the computing resources. Rather portions, or shares of the security system private key are stored at each of the computing resources within the security system and multiple security systems must communicate and share partial decryptions in order to decrypt the stored private key.
An Efficient Quantum Somewhat Homomorphic Symmetric Searchable Encryption
NASA Astrophysics Data System (ADS)
Sun, Xiaoqiang; Wang, Ting; Sun, Zhiwei; Wang, Ping; Yu, Jianping; Xie, Weixin
2017-01-01
In 2009, Gentry first introduced an ideal lattices fully homomorphic encryption (FHE) scheme. Later, based on the approximate greatest common divisor problem, learning with errors problem or learning with errors over rings problem, FHE has developed rapidly, along with the low efficiency and computational security. Combined with quantum mechanics, Liang proposed a symmetric quantum somewhat homomorphic encryption (QSHE) scheme based on quantum one-time pad, which is unconditional security. And it was converted to a quantum fully homomorphic encryption scheme, whose evaluation algorithm is based on the secret key. Compared with Liang's QSHE scheme, we propose a more efficient QSHE scheme for classical input states with perfect security, which is used to encrypt the classical message, and the secret key is not required in the evaluation algorithm. Furthermore, an efficient symmetric searchable encryption (SSE) scheme is constructed based on our QSHE scheme. SSE is important in the cloud storage, which allows users to offload search queries to the untrusted cloud. Then the cloud is responsible for returning encrypted files that match search queries (also encrypted), which protects users' privacy.
An Efficient Quantum Somewhat Homomorphic Symmetric Searchable Encryption
NASA Astrophysics Data System (ADS)
Sun, Xiaoqiang; Wang, Ting; Sun, Zhiwei; Wang, Ping; Yu, Jianping; Xie, Weixin
2017-04-01
In 2009, Gentry first introduced an ideal lattices fully homomorphic encryption (FHE) scheme. Later, based on the approximate greatest common divisor problem, learning with errors problem or learning with errors over rings problem, FHE has developed rapidly, along with the low efficiency and computational security. Combined with quantum mechanics, Liang proposed a symmetric quantum somewhat homomorphic encryption (QSHE) scheme based on quantum one-time pad, which is unconditional security. And it was converted to a quantum fully homomorphic encryption scheme, whose evaluation algorithm is based on the secret key. Compared with Liang's QSHE scheme, we propose a more efficient QSHE scheme for classical input states with perfect security, which is used to encrypt the classical message, and the secret key is not required in the evaluation algorithm. Furthermore, an efficient symmetric searchable encryption (SSE) scheme is constructed based on our QSHE scheme. SSE is important in the cloud storage, which allows users to offload search queries to the untrusted cloud. Then the cloud is responsible for returning encrypted files that match search queries (also encrypted), which protects users' privacy.
An Image Encryption Algorithm Utilizing Julia Sets and Hilbert Curves
Sun, Yuanyuan; Chen, Lina; Xu, Rudan; Kong, Ruiqing
2014-01-01
Image encryption is an important and effective technique to protect image security. In this paper, a novel image encryption algorithm combining Julia sets and Hilbert curves is proposed. The algorithm utilizes Julia sets’ parameters to generate a random sequence as the initial keys and gets the final encryption keys by scrambling the initial keys through the Hilbert curve. The final cipher image is obtained by modulo arithmetic and diffuse operation. In this method, it needs only a few parameters for the key generation, which greatly reduces the storage space. Moreover, because of the Julia sets’ properties, such as infiniteness and chaotic characteristics, the keys have high sensitivity even to a tiny perturbation. The experimental results indicate that the algorithm has large key space, good statistical property, high sensitivity for the keys, and effective resistance to the chosen-plaintext attack. PMID:24404181
An image encryption algorithm utilizing julia sets and hilbert curves.
Sun, Yuanyuan; Chen, Lina; Xu, Rudan; Kong, Ruiqing
2014-01-01
Image encryption is an important and effective technique to protect image security. In this paper, a novel image encryption algorithm combining Julia sets and Hilbert curves is proposed. The algorithm utilizes Julia sets' parameters to generate a random sequence as the initial keys and gets the final encryption keys by scrambling the initial keys through the Hilbert curve. The final cipher image is obtained by modulo arithmetic and diffuse operation. In this method, it needs only a few parameters for the key generation, which greatly reduces the storage space. Moreover, because of the Julia sets' properties, such as infiniteness and chaotic characteristics, the keys have high sensitivity even to a tiny perturbation. The experimental results indicate that the algorithm has large key space, good statistical property, high sensitivity for the keys, and effective resistance to the chosen-plaintext attack.
NASA Astrophysics Data System (ADS)
Bellare, Mihir; Ristenpart, Thomas; Rogaway, Phillip; Stegers, Till
Format-preserving encryption (FPE) encrypts a plaintext of some specified format into a ciphertext of identical format—for example, encrypting a valid credit-card number into a valid credit-card number. The problem has been known for some time, but it has lacked a fully general and rigorous treatment. We provide one, starting off by formally defining FPE and security goals for it. We investigate the natural approach for achieving FPE on complex domains, the “rank-then-encipher” approach, and explore what it can and cannot do. We describe two flavors of unbalanced Feistel networks that can be used for achieving FPE, and we prove new security results for each. We revisit the cycle-walking approach for enciphering on a non-sparse subset of an encipherable domain, showing that the timing information that may be divulged by cycle walking is not a damaging thing to leak.
A DNA-Inspired Encryption Methodology for Secure, Mobile Ad Hoc Networks
NASA Technical Reports Server (NTRS)
Shaw, Harry
2012-01-01
Users are pushing for greater physical mobility with their network and Internet access. Mobile ad hoc networks (MANET) can provide an efficient mobile network architecture, but security is a key concern. A figure summarizes differences in the state of network security for MANET and fixed networks. MANETs require the ability to distinguish trusted peers, and tolerate the ingress/egress of nodes on an unscheduled basis. Because the networks by their very nature are mobile and self-organizing, use of a Public Key Infra structure (PKI), X.509 certificates, RSA, and nonce ex changes becomes problematic if the ideal of MANET is to be achieved. Molecular biology models such as DNA evolution can provide a basis for a proprietary security architecture that achieves high degrees of diffusion and confusion, and resistance to cryptanalysis. A proprietary encryption mechanism was developed that uses the principles of DNA replication and steganography (hidden word cryptography) for confidentiality and authentication. The foundation of the approach includes organization of coded words and messages using base pairs organized into genes, an expandable genome consisting of DNA-based chromosome keys, and a DNA-based message encoding, replication, and evolution and fitness. In evolutionary computing, a fitness algorithm determines whether candidate solutions, in this case encrypted messages, are sufficiently encrypted to be transmitted. The technology provides a mechanism for confidential electronic traffic over a MANET without a PKI for authenticating users.
NASA Technical Reports Server (NTRS)
Bishop, Matt
1988-01-01
The organization of some tools to help improve passwork security at a UNIX-based site is described along with how to install and use them. These tools and their associated library enable a site to force users to pick reasonably safe passwords (safe being site configurable) and to enable site management to try to crack existing passworks. The library contains various versions of a very fast implementation of the Data Encryption Standard and of the one-way encryption functions used to encryp the password.
NASA Astrophysics Data System (ADS)
Liu, Yuexin; Metzner, John J.; Guo, Ruyan; Yu, Francis T. S.
2005-09-01
An efficient and secure algorithm for random phase mask generation used in optical data encryption and transmission system is proposed, based on Diffie-Hellman public key distribution. Thus-generated random mask has higher security due to the fact that it is never exposed to the vulnerable transmitting channels. The effectiveness to retrieve the original image and its robustness against blind manipulation have been demonstrated by our numerical results. In addition, this algorithm can be easily extended to multicast networking system and refresh of this shared random key is also very simple to implement.
Optical encryption using photon-counting polarimetric imaging.
Maluenda, David; Carnicer, Artur; Martínez-Herrero, Rosario; Juvells, Ignasi; Javidi, Bahram
2015-01-26
We present a polarimetric-based optical encoder for image encryption and verification. A system for generating random polarized vector keys based on a Mach-Zehnder configuration combined with translucent liquid crystal displays in each path of the interferometer is developed. Polarization information of the encrypted signal is retrieved by taking advantage of the information provided by the Stokes parameters. Moreover, photon-counting model is used in the encryption process which provides data sparseness and nonlinear transformation to enhance security. An authorized user with access to the polarization keys and the optical design variables can retrieve and validate the photon-counting plain-text. Optical experimental results demonstrate the feasibility of the encryption method.
Quantum Image Encryption Algorithm Based on Image Correlation Decomposition
NASA Astrophysics Data System (ADS)
Hua, Tianxiang; Chen, Jiamin; Pei, Dongju; Zhang, Wenquan; Zhou, Nanrun
2015-02-01
A novel quantum gray-level image encryption and decryption algorithm based on image correlation decomposition is proposed. The correlation among image pixels is established by utilizing the superposition and measurement principle of quantum states. And a whole quantum image is divided into a series of sub-images. These sub-images are stored into a complete binary tree array constructed previously and then randomly performed by one of the operations of quantum random-phase gate, quantum revolving gate and Hadamard transform. The encrypted image can be obtained by superimposing the resulting sub-images with the superposition principle of quantum states. For the encryption algorithm, the keys are the parameters of random phase gate, rotation angle, binary sequence and orthonormal basis states. The security and the computational complexity of the proposed algorithm are analyzed. The proposed encryption algorithm can resist brute force attack due to its very large key space and has lower computational complexity than its classical counterparts.
Attribute-Based Encryption with Partially Hidden Ciphertext Policies
NASA Astrophysics Data System (ADS)
Nishide, Takashi; Yoneyama, Kazuki; Ohta, Kazuo
We propose attribute-based encryption schemes where encryptor-specified policies (called ciphertext policies) are hidden. By using our schemes, an encryptor can encrypt data with a hidden access control policy. A decryptor obtains her secret key associated with her attributes from a trusted authority in advance and if the attributes associated with the decryptor's secret key do not satisfy the access control policy associated with the encrypted data, the decryptor cannot decrypt the data or guess even what access control policy was specified by the encryptor. We prove security of our construction based on the Decisional Bilinear Diffie-Hellman assumption and the Decision Linear assumption. In our security notion, even the legitimate decryptor cannot obtain the information about the access control policy associated with the encrypted data more than the fact that she can decrypt the data.
Photonic encryption using all optical logic.
Blansett, Ethan L.; Schroeppel, Richard Crabtree; Tang, Jason D.; Robertson, Perry J.; Vawter, Gregory Allen; Tarman, Thomas David; Pierson, Lyndon George
2003-12-01
With the build-out of large transport networks utilizing optical technologies, more and more capacity is being made available. Innovations in Dense Wave Division Multiplexing (DWDM) and the elimination of optical-electrical-optical conversions have brought on advances in communication speeds as we move into 10 Gigabit Ethernet and above. Of course, there is a need to encrypt data on these optical links as the data traverses public and private network backbones. Unfortunately, as the communications infrastructure becomes increasingly optical, advances in encryption (done electronically) have failed to keep up. This project examines the use of optical logic for implementing encryption in the photonic domain to achieve the requisite encryption rates. In order to realize photonic encryption designs, technology developed for electrical logic circuits must be translated to the photonic regime. This paper examines two classes of all optical logic (SEED, gain competition) and how each discrete logic element can be interconnected and cascaded to form an optical circuit. Because there is no known software that can model these devices at a circuit level, the functionality of the SEED and gain competition devices in an optical circuit were modeled in PSpice. PSpice allows modeling of the macro characteristics of the devices in context of a logic element as opposed to device level computational modeling. By representing light intensity as voltage, 'black box' models are generated that accurately represent the intensity response and logic levels in both technologies. By modeling the behavior at the systems level, one can incorporate systems design tools and a simulation environment to aid in the overall functional design. Each black box model of the SEED or gain competition device takes certain parameters (reflectance, intensity, input response), and models the optical ripple and time delay characteristics. These 'black box' models are interconnected and cascaded in an
Quantum asymmetric cryptography with symmetric keys
NASA Astrophysics Data System (ADS)
Gao, Fei; Wen, Qiaoyan; Qin, Sujuan; Zhu, Fuchen
2009-12-01
Based on quantum encryption, we present a new idea for quantum public-key cryptography (QPKC) and construct a whole theoretical framework of a QPKC system. We show that the quantum-mechanical nature renders it feasible and reasonable to use symmetric keys in such a scheme, which is quite different from that in conventional public-key cryptography. The security of our scheme is analyzed and some features are discussed. Furthermore, the state-estimation attack to a prior QPKC scheme is demonstrated.
Wikipedia: A Key Tool for Global Public Health Promotion
Heilman, James M; Kemmann, Eckhard; Bonert, Michael; Chatterjee, Anwesh; Ragar, Brent; Beards, Graham M; Iberri, David J; Harvey, Matthew; Thomas, Brendan; Stomp, Wouter; Martone, Michael F; Lodge, Daniel J; Vondracek, Andrea; de Wolff, Jacob F; Liber, Casimir; Grover, Samir C; Vickers, Tim J; Meskó, Bertalan
2011-01-01
The Internet has become an important health information resource for patients and the general public. Wikipedia, a collaboratively written Web-based encyclopedia, has become the dominant online reference work. It is usually among the top results of search engine queries, including when medical information is sought. Since April 2004, editors have formed a group called WikiProject Medicine to coordinate and discuss the English-language Wikipedia’s medical content. This paper, written by members of the WikiProject Medicine, discusses the intricacies, strengths, and weaknesses of Wikipedia as a source of health information and compares it with other medical wikis. Medical professionals, their societies, patient groups, and institutions can help improve Wikipedia’s health-related entries. Several examples of partnerships already show that there is enthusiasm to strengthen Wikipedia’s biomedical content. Given its unique global reach, we believe its possibilities for use as a tool for worldwide health promotion are underestimated. We invite the medical community to join in editing Wikipedia, with the goal of providing people with free access to reliable, understandable, and up-to-date health information. PMID:21282098
Chaos based encryption system for encrypting electroencephalogram signals.
Lin, Chin-Feng; Shih, Shun-Han; Zhu, Jin-De
2014-05-01
In the paper, we use the Microsoft Visual Studio Development Kit and C# programming language to implement a chaos-based electroencephalogram (EEG) encryption system involving three encryption levels. A chaos logic map, initial value, and bifurcation parameter for the map were used to generate Level I chaos-based EEG encryption bit streams. Two encryption-level parameters were added to these elements to generate Level II chaos-based EEG encryption bit streams. An additional chaotic map and chaotic address index assignment process was used to implement the Level III chaos-based EEG encryption system. Eight 16-channel EEG Vue signals were tested using the encryption system. The encryption was the most rapid and robust in the Level III system. The test yielded superior encryption results, and when the correct deciphering parameter was applied, the EEG signals were completely recovered. However, an input parameter error (e.g., a 0.00001 % initial point error) causes chaotic encryption bit streams, preventing the recovery of 16-channel EEG Vue signals.
A Literature Review on Image Encryption Techniques
NASA Astrophysics Data System (ADS)
Khan, Majid; Shah, Tariq
2014-12-01
Image encryption plays a paramount part to guarantee classified transmission and capacity of image over web. Then again, a real-time image encryption confronts a more noteworthy test because of vast measure of information included. This paper exhibits an audit on image encryption in spatial, frequency and hybrid domains with both full encryption and selective encryption strategy.
Fresnel domain double-phase encoding encryption of color image via ptychography
NASA Astrophysics Data System (ADS)
Qiao, Liang; Wang, Yali; Li, Tuo; Shi, Yishi
2015-10-01
In this paper, color image encryption combined with ptychography has been investigated. Ptychographic imaging possesses a remarkable advantage of simple optics architecture and complex amplitude of object can be reconstructed just by a series of diffraction intensity patterns via aperture movement. Traditional technique of three primary color synthesis is applied for encrypting color image. In order to reduce physical limitations, the encryption's algorithm is based on Fresnel transformation domain. It is illustrated that the proposed optical encryption scheme has well ability to recover the encrypted color plaintext and advances in security enhancement thanks to introducing ptychography, since light probe as key factor enlarges the key space. Finally, the encryption's immunity to noise and reconstruction impact from lateral offset of probe has been investigated.
Public key suppression and recovery using a PANDA ring resonator for high security communication
NASA Astrophysics Data System (ADS)
Juleang, Pakorn; Phongsanam, Prapas; Mitatha, Somsak; Yupapin, Preecha P.
2011-03-01
An interesting security technique that uses the dark-bright soliton conversion control within the microring resonator is proposed. The obtained outputs for a dark-bright soliton dynamic state can be controlled and used to form the public key suppression for communication security application. However, a good design should be possible to be fabricated; therefore, by using the parameters based on the practical device parameters, the simulation results obtained have shown that the proposed system can indeed be achieved. The public key suppression and public key recovery can be used in a highly secure communication system and has potential applications in optical cryptography.
A New Color Image Encryption Scheme Using CML and a Fractional-Order Chaotic System
Wu, Xiangjun; Li, Yang; Kurths, Jürgen
2015-01-01
The chaos-based image cryptosystems have been widely investigated in recent years to provide real-time encryption and transmission. In this paper, a novel color image encryption algorithm by using coupled-map lattices (CML) and a fractional-order chaotic system is proposed to enhance the security and robustness of the encryption algorithms with a permutation-diffusion structure. To make the encryption procedure more confusing and complex, an image division-shuffling process is put forward, where the plain-image is first divided into four sub-images, and then the position of the pixels in the whole image is shuffled. In order to generate initial conditions and parameters of two chaotic systems, a 280-bit long external secret key is employed. The key space analysis, various statistical analysis, information entropy analysis, differential analysis and key sensitivity analysis are introduced to test the security of the new image encryption algorithm. The cryptosystem speed is analyzed and tested as well. Experimental results confirm that, in comparison to other image encryption schemes, the new algorithm has higher security and is fast for practical image encryption. Moreover, an extensive tolerance analysis of some common image processing operations such as noise adding, cropping, JPEG compression, rotation, brightening and darkening, has been performed on the proposed image encryption technique. Corresponding results reveal that the proposed image encryption method has good robustness against some image processing operations and geometric attacks. PMID:25826602
A new color image encryption scheme using CML and a fractional-order chaotic system.
Wu, Xiangjun; Li, Yang; Kurths, Jürgen
2015-01-01
The chaos-based image cryptosystems have been widely investigated in recent years to provide real-time encryption and transmission. In this paper, a novel color image encryption algorithm by using coupled-map lattices (CML) and a fractional-order chaotic system is proposed to enhance the security and robustness of the encryption algorithms with a permutation-diffusion structure. To make the encryption procedure more confusing and complex, an image division-shuffling process is put forward, where the plain-image is first divided into four sub-images, and then the position of the pixels in the whole image is shuffled. In order to generate initial conditions and parameters of two chaotic systems, a 280-bit long external secret key is employed. The key space analysis, various statistical analysis, information entropy analysis, differential analysis and key sensitivity analysis are introduced to test the security of the new image encryption algorithm. The cryptosystem speed is analyzed and tested as well. Experimental results confirm that, in comparison to other image encryption schemes, the new algorithm has higher security and is fast for practical image encryption. Moreover, an extensive tolerance analysis of some common image processing operations such as noise adding, cropping, JPEG compression, rotation, brightening and darkening, has been performed on the proposed image encryption technique. Corresponding results reveal that the proposed image encryption method has good robustness against some image processing operations and geometric attacks.
Lighten Encryption Schemes for Secure and Private RFID Systems
NASA Astrophysics Data System (ADS)
Canard, Sébastien; Coisel, Iwen; Etrog, Jonathan
We provide several concrete implementations of a generic method given by Vaudenay to construct secure privacy-preserving RFID authentication and identification systems. More precisely, we give the first instantiation of the Vaudenay's result by using the IND-CCA secure DHAES cryptosystem. Next we argue that weaker cryptosystems can also be used by recalling the WIPR RFID system and giving a new protocol based on the El Gamal encryption scheme. After that, we introduce a new generic construction based on the use of any IND-CPA secure public key cryptosystem together with a MAC scheme and describe a possibility using the Hash El Gamal cryptosystem. We finally compare all these schemes, both in terms of implementation and security, proving that, nowadays the DHAES and our Hash El Gamal based solutions appear as the most promising schemes.
Chaotic Order Preserving Encryption for Efficient and Secure Queries on Databases
NASA Astrophysics Data System (ADS)
Lee, Seungmin; Park, Tae-Jun; Lee, Donghyeok; Nam, Taekyong; Kim, Sehun
The need for data encryption that protects sensitive data in a database has increased rapidly. However, encrypted data can no longer be efficiently queried because nearly all of the data should be decrypted. Several order-preserving encryption schemes that enable indexes to be built over encrypted data have been suggested to solve this problem. They allow any comparison operation to be directly applied to encrypted data. However, one of the main disadvantages of these schemes is that they expose sensitive data to inference attacks with order information, especially when the data are used together with unencrypted columns in the database. In this study, a new order-preserving encryption scheme that provides secure queries by hiding the order is introduced. Moreover, it provides efficient queries because any user who has the encryption key knows the order. The proposed scheme is designed to be efficient and secure in such an environment. Thus, it is possible to encrypt only sensitive data while leaving other data unencrypted. The encryption is not only robust against order exposure, but also shows high performance for any query over encrypted data. In addition, the proposed scheme provides strong updates without assumptions of the distribution of plaintext. This allows it to be integrated easily with the existing database system.
Data publication and dissemination of interactive keys under the open access model
Technology Transfer Automated Retrieval System (TEKTRAN)
The concepts of publication, citation and dissemination of interactive keys and other online keys are discussed and illustrated by a sample paper published in the present issue (doi: 10.3897/zookeys.21.271). The present model is based on previous experience with several existing examples of publishi...
Public-Private Partnerships: The Key to Retaining Government and Industry Capabilities
2013-02-01
government and industry to optimize weapon system product support at best value cost. Public - Private Partnerships (PPPs) are a key component of DoD...program offices, inventory control points, and sustainment commands, may be parties to such agreements. DoD Policy on Public - Private Partnerships DoD...policy on public - private partnerships is reflected in DoDD 5000.01, The Defense Acquisition System, paragraph E1.17, certified current as of Nov. 20
NASA Astrophysics Data System (ADS)
Knobler, Ron; Scheffel, Peter; Jackson, Scott; Gaj, Kris; Kaps, Jens Peter
2013-05-01
Various embedded systems, such as unattended ground sensors (UGS), are deployed in dangerous areas, where they are subject to compromise. Since numerous systems contain a network of devices that communicate with each other (often times with commercial off the shelf [COTS] radios), an adversary is able to intercept messages between system devices, which jeopardizes sensitive information transmitted by the system (e.g. location of system devices). Secret key algorithms such as AES are a very common means to encrypt all system messages to a sufficient security level, for which lightweight implementations exist for even very resource constrained devices. However, all system devices must use the appropriate key to encrypt and decrypt messages from each other. While traditional public key algorithms (PKAs), such as RSA and Elliptic Curve Cryptography (ECC), provide a sufficiently secure means to provide authentication and a means to exchange keys, these traditional PKAs are not suitable for very resource constrained embedded systems or systems which contain low reliability communication links (e.g. mesh networks), especially as the size of the network increases. Therefore, most UGS and other embedded systems resort to pre-placed keys (PPKs) or other naïve schemes which greatly reduce the security and effectiveness of the overall cryptographic approach. McQ has teamed with the Cryptographic Engineering Research Group (CERG) at George Mason University (GMU) to develop an approach using revolutionary cryptographic techniques that provides both authentication and encryption, but on resource constrained embedded devices, without the burden of large amounts of key distribution or storage.
Image compression-encryption scheme based on hyper-chaotic system and 2D compressive sensing
NASA Astrophysics Data System (ADS)
Zhou, Nanrun; Pan, Shumin; Cheng, Shan; Zhou, Zhihong
2016-08-01
Most image encryption algorithms based on low-dimensional chaos systems bear security risks and suffer encryption data expansion when adopting nonlinear transformation directly. To overcome these weaknesses and reduce the possible transmission burden, an efficient image compression-encryption scheme based on hyper-chaotic system and 2D compressive sensing is proposed. The original image is measured by the measurement matrices in two directions to achieve compression and encryption simultaneously, and then the resulting image is re-encrypted by the cycle shift operation controlled by a hyper-chaotic system. Cycle shift operation can change the values of the pixels efficiently. The proposed cryptosystem decreases the volume of data to be transmitted and simplifies the keys distribution simultaneously as a nonlinear encryption system. Simulation results verify the validity and the reliability of the proposed algorithm with acceptable compression and security performance.
NASA Astrophysics Data System (ADS)
Yi, Lilin; Zhang, Tao; Hu, Weisheng
2011-11-01
A novel all-optical encryption/decryption method based on stimulated Brillouin scattering (SBS) effect in optical fiber is proposed for the first time. The operation principle is explained in detail and the encryption and decryption performance is experimentally evaluated. The encryption keys could be the SBS gain amplitude, bandwidth, central wavelength and spectral shape, which are configurable and flexibly controlled by the users. We experimentally demonstrate the SBS encryption/decryption process of a 10.86-Gb/s non-return-to-zero (NRZ) data by using both phase-modulated and current-dithered Brillouin pumps for proof-of-concept. Unlike the traditional optical encryption methods of chaotic communications and optical code-division-multiplexing access (OCDMA), the SBS based encryption/decryption technique can directly upgrade the current optical communication system to a secure communication system without changing the terminal transceivers, which is completely compatible with the current optical communication systems.
Securing Voice over IP Conferencing with Decentralized Group Encryption
2007-09-04
98 Appendix C Installation Guide ...Similarly, system users should peruse the installation guide . Chapter 2 defines the problem we aim to solve with this project. We review motivation...membership changes. These keys are used in Cipher Block Chaining (CBC) mode to encrypt message payloads. After a group key is distributed, PKGE can
Optical field encryption for secure transmission of data
NASA Astrophysics Data System (ADS)
Fraser, Colin B.; Harvey, Andrew R.
2004-12-01
The growing awareness of the vulnerability of information transmitted on communication systems within the government, military and commercial sectors, has stimulated a number of areas of research within the optical community to design optical hardware encryption systems providing inherent immunity to espionage techniques. This paper describes a hardware optical encryption technique that utilises off the shelf telecommunication equipment and negates the necessity for an independent key distribution system with respect to the data transmission system, as is common with alternative encryption system implementations. This method also lends itself easily to fiber optic or free space communication and is applicable within any optical waveband. The encryption-decryption of the optical signal is achieved through low coherence optical interferometry. This requires the instantaneous processing and analysis of the signal, optically, to retrieve the relevant optical phase information hidden in the transmitted optical noise. This technology allows an authorised user to transmit encrypted information at a high data rate securely, while maintaining opaqueness to an unauthorised observer that data transmission is occurring. As the instantaneous optical field properties of the signals present in the system are essential to the optical encryption - decryption process, the system is inherently protected against electronic recording and advances in computational decryption algorithms. For organisations wishing to protect sensitive data and levels of communication activity these are highly desirable features.
Secure Genomic Computation through Site-Wise Encryption.
Zhao, Yongan; Wang, XiaoFeng; Tang, Haixu
2015-01-01
Commercial clouds provide on-demand IT services for big-data analysis, which have become an attractive option for users who have no access to comparable infrastructure. However, utilizing these services for human genome analysis is highly risky, as human genomic data contains identifiable information of human individuals and their disease susceptibility. Therefore, currently, no computation on personal human genomic data is conducted on public clouds. To address this issue, here we present a site-wise encryption approach to encrypt whole human genome sequences, which can be subject to secure searching of genomic signatures on public clouds. We implemented this method within the Hadoop framework, and tested it on the case of searching disease markers retrieved from the ClinVar database against patients' genomic sequences. The secure search runs only one order of magnitude slower than the simple search without encryption, indicating our method is ready to be used for secure genomic computation on public clouds.
Cancelable face verification using optical encryption and authentication.
Taheri, Motahareh; Mozaffari, Saeed; Keshavarzi, Parviz
2015-10-01
In a cancelable biometric system, each instance of enrollment is distorted by a transform function, and the output should not be retransformed to the original data. This paper presents a new cancelable face verification system in the encrypted domain. Encrypted facial images are generated by a double random phase encoding (DRPE) algorithm using two keys (RPM1 and RPM2). To make the system noninvertible, a photon counting (PC) method is utilized, which requires a photon distribution mask for information reduction. Verification of sparse images that are not recognizable by direct visual inspection is performed by unconstrained minimum average correlation energy filter. In the proposed method, encryption keys (RPM1, RPM2, and PDM) are used in the sender side, and the receiver needs only encrypted images and correlation filters. In this manner, the system preserves privacy if correlation filters are obtained by an adversary. Performance of PC-DRPE verification system is evaluated under illumination variation, pose changes, and facial expression. Experimental results show that utilizing encrypted images not only increases security concerns but also enhances verification performance. This improvement can be attributed to the fact that, in the proposed system, the face verification problem is converted to key verification tasks.
Encryption and networking applications
Long, J.P.
1995-04-01
The DOE requires that sensitive unclassified data be protected while being transmitted electronically. On most large networks it is difficult and expensive to provide the required level of physical protection. At Sandia National Laboratories, we are assembling the structure necessary to protect sensitive unclassified data using software-based encryption. This approach has the advantage that the data can be protected after arrival at its destination without additional investment While Sandia has expertise in cryptography, we had not used cryptography in this field. This discussion deals with the client-server model of file-based data exchange and interactive access to on-line data bases using Unix workstations, Macs and PCs.
Integrating end-to-end encryption and authentication technology into broadband networks
Pierson, L.G.
1995-11-01
BISDN services will involve the integration of high speed data, voice, and video functionality delivered via technology similar to Asynchronous Transfer Mode (ATM) switching and SONET optical transmission systems. Customers of BISDN services may need a variety of data authenticity and privacy assurances, via Asynchronous Transfer Mode (ATM) services Cryptographic methods can be used to assure authenticity and privacy, but are hard to scale for implementation at high speed. The incorporation of these methods into computer networks can severely impact functionality, reliability, and performance. While there are many design issues associated with the serving of public keys for authenticated signaling and for establishment of session cryptovariables, this paper is concerned with the impact of encryption itself on such communications once the signaling and setup have been completed. Network security protections should be carefully matched to the threats against which protection is desired. Even after eliminating unnecessary protections, the remaining customer-required network security protections can impose severe performance penalties. These penalties (further discussed below) usually involve increased communication processing for authentication or encryption, increased error rate, increased communication delay, and decreased reliability/availability. Protection measures involving encryption should be carefully engineered so as to impose the least performance, reliability, and functionality penalties, while achieving the required security protection. To study these trade-offs, a prototype encryptor/decryptor was developed. This effort demonstrated the viability of implementing certain encryption techniques in high speed networks. The research prototype processes ATM cells in a SONET OC-3 payload. This paper describes the functionality, reliability, security, and performance design trade-offs investigated with the prototype.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 5 2010-10-01 2010-10-01 false Encryption. 90.553 Section 90.553...-805 MHz Bands § 90.553 Encryption. (a) Encryption is permitted on all but the two nationwide Interoperability calling channels. Radios employing encryption must have a readily accessible switch or...
Code of Federal Regulations, 2013 CFR
2013-10-01
... 47 Telecommunication 5 2013-10-01 2013-10-01 false Encryption. 90.553 Section 90.553...-805 MHz Bands § 90.553 Encryption. (a) Encryption is permitted on all but the two nationwide Interoperability calling channels. Radios employing encryption must have a readily accessible switch or...
Code of Federal Regulations, 2011 CFR
2011-10-01
... 47 Telecommunication 5 2011-10-01 2011-10-01 false Encryption. 90.553 Section 90.553...-805 MHz Bands § 90.553 Encryption. (a) Encryption is permitted on all but the two nationwide Interoperability calling channels. Radios employing encryption must have a readily accessible switch or...
Code of Federal Regulations, 2012 CFR
2012-10-01
... 47 Telecommunication 5 2012-10-01 2012-10-01 false Encryption. 90.553 Section 90.553...-805 MHz Bands § 90.553 Encryption. (a) Encryption is permitted on all but the two nationwide Interoperability calling channels. Radios employing encryption must have a readily accessible switch or...
NASA Astrophysics Data System (ADS)
Su, Yonggang; Tang, Chen; Chen, Xia; Li, Biyuan; Xu, Wenjun; Lei, Zhenkun
2017-01-01
We propose an image encryption scheme using chaotic phase masks and cascaded Fresnel transform holography based on a constrained optimization algorithm. In the proposed encryption scheme, the chaotic phase masks are generated by Henon map, and the initial conditions and parameters of Henon map serve as the main secret keys during the encryption and decryption process. With the help of multiple chaotic phase masks, the original image can be encrypted into the form of a hologram. The constrained optimization algorithm makes it possible to retrieve the original image from only single frame hologram. The use of chaotic phase masks makes the key management and transmission become very convenient. In addition, the geometric parameters of optical system serve as the additional keys, which can improve the security level of the proposed scheme. Comprehensive security analysis performed on the proposed encryption scheme demonstrates that the scheme has high resistance against various potential attacks. Moreover, the proposed encryption scheme can be used to encrypt video information. And simulations performed on a video in AVI format have also verified the feasibility of the scheme for video encryption.
An improved key agreement protocol based on chaos
NASA Astrophysics Data System (ADS)
Wang, Xingyuan; Zhao, Jianfeng
2010-12-01
Cryptography based on chaos theory has developed fast in the past few years, but most of the researches focus on secret key cryptography. There are few public key encryption algorithms and cryptographic protocols based on chaos, which are also of great importance for network security. We introduce an enhanced key agreement protocol based on Chebyshev chaotic map. Utilizing the semi-group property of Chebyshev polynomials, the proposed key exchange algorithm works like Diffie-Hellman algorithm. The improved protocol overcomes the drawbacks of several previously proposed chaotic key agreement protocols. Both analytical and experimental results show that it is effective and secure.
Design and Realisation of Chaotic Encryption Systems
NASA Astrophysics Data System (ADS)
Schwarz, Wolfgang; Falk, Thomas
2002-07-01
Chaotic signal transmission systems are often claimed to be secure by itself. Using a simple example it is shown, that this is not true and that exact design criteria have to be set up before starting the design of a chaotic encryption system. Then, beginning with statistical design objectives an information encryption system is systematically designed. The structure design leads to a controlled filter structure with overflow nonlinearity, the parameter design has to assure chaotic behaviour and mixing properties of the encoded signal. This defines the limits for the choice of the parameter set representing the key for the encryption. After developing the system structure the system is realized by electronic circuitry. Discrete and IC versions of the solution are presented. In order to prove that the system meets the design requirements experimental results are provided. It can be shown that in a n-th order system the statistical characteristics up to the n-th order of the output signal will not be affected by the input signal. The paper closes with some security estimates for the designed system.
2007-11-02
Common Criteria for Information Technology Security Evaluation Department of Defense Public Key Infrastructure and Key Management ...for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and...Infrastructure and Key Management Infrastructure Token Protection Profile (Medium Reobustness) 5. FUNDING NUMBERS 6. AUTHOR(S) 7. PERFORMING ORGANIZATION
An asymmetric color image encryption method by using deduced gyrator transform
NASA Astrophysics Data System (ADS)
Yao, Lili; Yuan, Caojin; Qiang, Junjie; Feng, Shaotong; Nie, Shouping
2017-02-01
An encryption algorithm is proposed by using the properties of deduced gyrator transform (GT). After being transformed by the GT algorithm and multiplied by a phase distribution p*, the spectrum modulus of the input image is considered to be the encrypted image by further performing Fourier transformation. To resist the attack from iterative phase retrieval, the red, green and blue components of the input image is modulated by a random phase mask and then combined using convolution. The encryption result is real-valued, which is convenient for display, transmission and storage. In the decryption process, the three original color components can be recovered with decryption keys which are different from the encryption keys. An optoelectronic hybrid system for the encryption process is also presented. Computer simulations are presented to demonstrate its performance, and the security of the proposed system is analyzed as well.
NASA Astrophysics Data System (ADS)
Tan, Ru-Chao; Lei, Tong; Zhao, Qing-Min; Gong, Li-Hua; Zhou, Zhi-Hong
2016-12-01
To improve the slow processing speed of the classical image encryption algorithms and enhance the security of the private color images, a new quantum color image encryption algorithm based on a hyper-chaotic system is proposed, in which the sequences generated by the Chen's hyper-chaotic system are scrambled and diffused with three components of the original color image. Sequentially, the quantum Fourier transform is exploited to fulfill the encryption. Numerical simulations show that the presented quantum color image encryption algorithm possesses large key space to resist illegal attacks, sensitive dependence on initial keys, uniform distribution of gray values for the encrypted image and weak correlation between two adjacent pixels in the cipher-image.
Rajput, Sudheesh K; Nishchal, Naveen K
2013-06-20
In this paper, an image encryption scheme based on polarized light encoding and a phase-truncation approach in the Fresnel transform domain is proposed. The phase-truncated data obtained by an asymmetric cryptosystem is encrypted and decrypted by using the concept of the Stokes-Mueller formalism. Image encryption based on polarization of light using Stokes-Mueller formalism has the main advantage over Jones vector formalism that it manipulates only intensity information, which is measurable. Thus any intensity information can be encrypted and decrypted using this scheme. The proposed method offers several advantages: (1) a lens-free setup, (2) flexibility in the encryption key design, (3) use of asymmetric keys, and (4) immunity against special attack. We present numerical simulation results for gray-scale and color images in support of the proposed security scheme. The performance measurement parameters relative error and correlation coefficient have been calculated to check the effectiveness of the scheme.
Lang, Jun
2012-01-30
In this paper, we propose a novel secure image sharing scheme based on Shamir's three-pass protocol and the multiple-parameter fractional Fourier transform (MPFRFT), which can safely exchange information with no advance distribution of either secret keys or public keys between users. The image is encrypted directly by the MPFRFT spectrum without the use of phase keys, and information can be shared by transmitting the encrypted image (or message) three times between users. Numerical simulation results are given to verify the performance of the proposed algorithm.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-03
... Department of the Army Requirement for Commercial Users To Use Commercial Public Key Information (PKI... commercial accounts accessing transportation systems and applications to use a commercial PKI certificate or... commercial entities by the Surface Deployment and Distribution Command, the United States Department of...
A Training Framework for the Department of Defense Public Key Infrastructure
2001-09-01
and the growth of electronic commerce within the Department of Defense (DoD) has led to the development and implementation of the DoD Public Key...also grown within the Department of Defense. Electronic commerce and business to business transactions have become more commonplace and have
Formalizing GDOI Group Key Management Requirements in NPATRL
2001-01-01
Controller and Key Server ( GCKS ) to distribute keys to members of a group. Although it does not specify any mechanisms such as key hierarchies [2] for...soundness. GDOI uses three categories of keys. Category 1 keys are the pairwise keys shared between the GCKS and potential members. Category 2 keys are key...Phase 1, which is described in [7, 5]. Key-encryption keys and traffic-encryption keys are created by the GCKS . The GCKS distributes these keys to
Lensless multiple-image optical encryption based on improved phase retrieval algorithm.
Huang, Jian-Ji; Hwang, Hone-Ene; Chen, Chun-Yuan; Chen, Ching-Mu
2012-05-01
A novel architecture of the optical multiple-image encryption based on the modified Gerchberg-Saxton algorithm (MGSA) by using cascading phase only functions (POFs) in the Fresnel transform (FrT) domain is presented. This proposed method can greatly increase the capacity of the system by avoiding the crosstalk, completely, between the encrypted target images. Each present stage encrypted target image is encoded as to a complex function by using the MGSA with constraining the encrypted target image of the previous stage. Not only the wavelength and position parameters in the FrT domain can be keys to increase system security, the created POFs are also served mutually as the encryption keys to decrypt target image from present stage into next stage in the cascaded scheme. Compared with a prior method [Appl. Opt.48, 2686-2692 (2009)], the main advantages of this proposed encryption system is that it does not need any transformative lenses and this makes it very efficient and easy to implement optically. Simulation results show that this proposed encryption system can successfully achieve the multiple-image encryption via fewer POFs, which is more advantageous in simpler implementation and efficiency than a prior method where each decryption stage requires two POFs to accomplish this task.
Optical image encryption technique based on deterministic phase masks
NASA Astrophysics Data System (ADS)
Zamrani, Wiam; Ahouzi, Esmail; Lizana, Angel; Campos, Juan; Yzuel, María J.
2016-10-01
The double-random phase encoding (DRPE) scheme, which is based on a 4f optical correlator system, is considered as a reference for the optical encryption field. We propose a modification of the classical DRPE scheme based on the use of a class of structured phase masks, the deterministic phase masks. In particular, we propose to conduct the encryption process by using two deterministic phase masks, which are built from linear combinations of several subkeys. For the decryption step, the input image is retrieved by using the complex conjugate of the deterministic phase masks, which were set in the encryption process. This concept of structured masks gives rise to encryption-decryption keys which are smaller and more compact than those required in the classical DRPE. In addition, we show that our method significantly improves the tolerance of the DRPE method to shifts of the decrypting phase mask-when no shift is applied, it provides similar performance to the DRPE scheme in terms of encryption-decryption results. This enhanced tolerance to the shift, which is proven by providing numerical simulation results for grayscale and binary images, may relax the rigidity of an encryption-decryption experimental implementation setup. To evaluate the effectiveness of the described method, the mean-square-error and the peak signal-to-noise ratio between the input images and the recovered images are calculated. Different studies based on simulated data are also provided to highlight the suitability and robustness of the method when applied to the image encryption-decryption processes.
Optimal encryption of quantum bits
Boykin, P. Oscar; Roychowdhury, Vwani
2003-04-01
We show that 2n random classical bits are both necessary and sufficient for encrypting any unknown state of n quantum bits in an informationally secure manner. We also characterize the complete set of optimal protocols in terms of a set of unitary operations that comprise an orthonormal basis in a canonical inner product space. Moreover, a connection is made between quantum encryption and quantum teleportation that allows for a different proof of optimality of teleportation.
Helping Students Adapt to Computer-Based Encrypted Examinations
ERIC Educational Resources Information Center
Baker-Eveleth, Lori; Eveleth, Daniel M.; O'Neill, Michele; Stone, Robert W.
2006-01-01
The College of Business and Economics at the University of Idaho conducted a pilot study that used commercially available encryption software called Securexam to deliver computer-based examinations. A multi-step implementation procedure was developed, implemented, and then evaluated on the basis of what students viewed as valuable. Two key aspects…
Pierson, L.G.; Witzke, E.L.
1999-01-01
This effort studied the integration of innovative methods of key management crypto synchronization, and key agility while scaling encryption speed. Viability of these methods for encryption of ATM cell payloads at the SONET OC- 192 data rate (10 Gb/s), and for operation at OC-48 rates (2.5 Gb/s) was shown. An SNL-Developed pipelined DES design was adapted for the encryption of ATM cells. A proof-of-principle prototype circuit board containing 11 Electronically Programmable Logic Devices (each holding the equivalent of 100,000 gates) was designed, built, and used to prototype a high speed encryptor.
Optical encryption/decryption of 8PSK signal using FWM-based modified XOR.
Zhang, Min; Cui, Yue; Zhan, Yueying; Zhang, Zhiguo; Chen, Xue
2015-09-01
A scheme for optical encryption/decryption of an eight-phase-shift keying (8PSK) signal is proposed, and this scheme applies modified optical XOR gates based on four-wave mixing (FWM) in a semiconductor optical amplifier (SOA). Theoretical analyses and simulations are conducted. Both the performance and the parameter design of a 40-Gbit/s all-optical encryption/decryption system under various key parameters are studied. The results are useful for designing optical encryption/decryption for complex modulated signals.
Scalable encryption using alpha rooting
NASA Astrophysics Data System (ADS)
Wharton, Eric J.; Panetta, Karen A.; Agaian, Sos S.
2008-04-01
Full and partial encryption methods are important for subscription based content providers, such as internet and cable TV pay channels. Providers need to be able to protect their products while at the same time being able to provide demonstrations to attract new customers without giving away the full value of the content. If an algorithm were introduced which could provide any level of full or partial encryption in a fast and cost effective manner, the applications to real-time commercial implementation would be numerous. In this paper, we present a novel application of alpha rooting, using it to achieve fast and straightforward scalable encryption with a single algorithm. We further present use of the measure of enhancement, the Logarithmic AME, to select optimal parameters for the partial encryption. When parameters are selected using the measure, the output image achieves a balance between protecting the important data in the image while still containing a good overall representation of the image. We will show results for this encryption method on a number of images, using histograms to evaluate the effectiveness of the encryption.
Optical stream-cipher-like system for image encryption based on Michelson interferometer.
Yang, Bing; Liu, Zhengjun; Wang, Bo; Zhang, Yan; Liu, Shutian
2011-01-31
A novel optical image encryption scheme based on interference is proposed. The original image is digitally encoded into one phase-only mask by employing an improved Gerchberg-Saxton phase retrieval algorithm together with another predefined random phase mask which serves as the encryption key. The decryption process can be implemented optically based on Michelson interferometer by using the same key. The scheme can be regarded as a stream-cipher-like encryption system, the encryption and decryption keys are the same, however the operations are different. The position coordinates and light wavelength can also be used as additional keys during the decryption. Numerical simulations have demonstrated the validity and robustness of the proposed method.
Fast encryption of image data using chaotic Kolmogorov flows
NASA Astrophysics Data System (ADS)
Scharinger, Josef
1997-01-01
To guarantee security and privacy in image transmission and archival applications, adequate efficient bulk encryption techniques are necessary which are able to cope with the vast amounts of image data involved. Experience has shown that block-oriented symmetric product ciphers constitute an adequate design paradigm for resolving this task, since they can offer a very high level of security as well as very high encryption rates. In this contribution we introduce a new product cipher which encrypts large blocks of plain-text (images) by repeated intertwined application of substitution and permutation operations. While almost all of the current product ciphers used fixed (predefined) permutation operations on small data blocks, our approach involves parameterizable (keyed) permutations on large data blocks (whole images) induced by specific chaotic systems (Kolmogorov flows). By combining these highly unstable dynamics with an adaption of a very fast shift register based pseudo-random number generator we obtain a new class of computationally secure product ciphers which are firmly grounded on systems theoretic concepts, offering many features that make them superior to contemporary bulk encryption systems when aiming at efficient image data encryption.
Color image encryption based on gyrator transform and Arnold transform
NASA Astrophysics Data System (ADS)
Sui, Liansheng; Gao, Bo
2013-06-01
A color image encryption scheme using gyrator transform and Arnold transform is proposed, which has two security levels. In the first level, the color image is separated into three components: red, green and blue, which are normalized and scrambled using the Arnold transform. The green component is combined with the first random phase mask and transformed to an interim using the gyrator transform. The first random phase mask is generated with the sum of the blue component and a logistic map. Similarly, the red component is combined with the second random phase mask and transformed to three-channel-related data. The second random phase mask is generated with the sum of the phase of the interim and an asymmetrical tent map. In the second level, the three-channel-related data are scrambled again and combined with the third random phase mask generated with the sum of the previous chaotic maps, and then encrypted into a gray scale ciphertext. The encryption result has stationary white noise distribution and camouflage property to some extent. In the process of encryption and decryption, the rotation angle of gyrator transform, the iterative numbers of Arnold transform, the parameters of the chaotic map and generated accompanied phase function serve as encryption keys, and hence enhance the security of the system. Simulation results and security analysis are presented to confirm the security, validity and feasibility of the proposed scheme.
Quantum image encryption based on restricted geometric and color transformations
NASA Astrophysics Data System (ADS)
Song, Xian-Hua; Wang, Shen; Abd El-Latif, Ahmed A.; Niu, Xia-Mu
2014-08-01
A novel encryption scheme for quantum images based on restricted geometric and color transformations is proposed. The new strategy comprises efficient permutation and diffusion properties for quantum image encryption. The core idea of the permutation stage is to scramble the codes of the pixel positions through restricted geometric transformations. Then, a new quantum diffusion operation is implemented on the permutated quantum image based on restricted color transformations. The encryption keys of the two stages are generated by two sensitive chaotic maps, which can ensure the security of the scheme. The final step, measurement, is built by the probabilistic model. Experiments conducted on statistical analysis demonstrate that significant improvements in the results are in favor of the proposed approach.
Arbitrarily modulated beam for phase-only optical encryption
NASA Astrophysics Data System (ADS)
Chen, Wen; Chen, Xudong
2014-10-01
Optical encryption has attracted more and more attention recently due to its remarkable advantages, such as parallel processing and multiple-dimensional characteristics. In this paper, we propose to apply an arbitrarily modulated beam for phase-only optical encryption. In optical security systems, the plane wave is commonly used for the illumination, and unauthorized receivers may easily obtain or estimate the information related to the illumination beam. The proposed strategy with an arbitrarily modulated illumination beam can effectively enhance system security, since a beam modulation pattern (such as a pinhole-array pattern or a random phase-only pattern) can be considered an additional security key. The phase-only optical encryption is taken as an example for illustrating the validity of the proposed method; however it could be straightforward to apply the proposed strategy to other optical security systems.
Asymmetric color image encryption based on singular value decomposition
NASA Astrophysics Data System (ADS)
Yao, Lili; Yuan, Caojin; Qiang, Junjie; Feng, Shaotong; Nie, Shouping
2017-02-01
A novel asymmetric color image encryption approach by using singular value decomposition (SVD) is proposed. The original color image is encrypted into a ciphertext shown as an indexed image by using the proposed method. The red, green and blue components of the color image are subsequently encoded into a complex function which is then separated into U, S and V parts by SVD. The data matrix of the ciphertext is obtained by multiplying orthogonal matrices U and V while implementing phase-truncation. Diagonal entries of the three diagonal matrices of the SVD results are abstracted and scrambling combined to construct the colormap of the ciphertext. Thus, the encrypted indexed image covers less space than the original image. For decryption, the original color image cannot be recovered without private keys which are obtained from phase-truncation and the orthogonality of V. Computer simulations are presented to evaluate the performance of the proposed algorithm. We also analyze the security of the proposed system.
NASA Astrophysics Data System (ADS)
Xi, Si-xing; Wang, Xiaolei; Sun, Xin; Chang, Shengjiang; Lin, Lie
2014-01-01
We propose a new method of image encryption using Fourier computer-generated hologram (CGH) in the encryption system of multiple Fresnel diffraction transforms with phase masks. The digital image to be encrypted is modulated by a series of three random-phase masks in Fresnel diffraction system and finally is transformed into a complex-amplitude image which is stationary white noise (in which the information is like stationary-white-noise). Because the complex-amplitude information is not easy to be directly saved, the binary real value Fourier CGH is applied to record it. Compared with the traditional double random-phase image encryption technology, this method adds new keys which enhance the image encryption security and the Fourier CGH greatly improves the antinoise performance.
Nghiem, Nhung; Genç, Murat; Blakely, Tony
2013-01-01
Pricing policies such as taxes and subsidies are important tools in preventing and controlling a range of threats to public health. This is particularly so in tobacco and alcohol control efforts and efforts to change dietary patterns and physical activity levels as a means of addressing increases in noncommunicable diseases. To understand the potential impact of pricing policies, it is critical to understand the nature of price elasticities for consumer products. For example, price elasticities are key parameters in models of any food tax or subsidy that aims to quantify health impacts and cost-effectiveness. We detail relevant terms and discuss key issues surrounding price elasticities to inform public health research and intervention studies. PMID:24028228
Flear, Mark L
2016-03-01
The replacement of the European Union (EU) Clinical Trials Directive by the new Clinical Trials Regulation (CTR), which entered into force on 16 June 2014 but will not apply before 28 May 2016, provides an opportunity to review the legal and political context within which this important aspect of research law and policy sits and to reflect on the implications for public health. My aim in this article is to relate the context to the key purposes and aims of EU law and policy on clinical trials in order to explain and clarify its orientation. On that basis, I argue that the CTR and the changes it introduces to the law on clinical trials are part of the EU's continued focus on market optimisation. It is this focus that orients and directs the wider pharmaceutical development pipeline, but that undermines the achievement of key public health objectives.
Lu, Yang; Li, Jiguo
2014-01-01
Signcryption is a useful cryptographic primitive that achieves confidentiality and authentication in an efficient manner. As an extension of signcryption in certificate-based cryptography, certificate-based signcryption preserves the merits of certificate-based cryptography and signcryption simultaneously. In this paper, we present an improved security model of certificate-based signcryption that covers both public key replacement attack and insider security. We show that an existing certificate-based signcryption scheme is insecure in our model. We also propose a new certificate-based signcryption scheme that achieves security against both public key replacement attacks and insider attacks. We prove in the random oracle model that the proposed scheme is chosen-ciphertext secure and existentially unforgeable. Performance analysis shows that the proposed scheme outperforms all the previous certificate-based signcryption schemes in the literature.
Nghiem, Nhung; Wilson, Nick; Genç, Murat; Blakely, Tony
2013-11-01
Pricing policies such as taxes and subsidies are important tools in preventing and controlling a range of threats to public health. This is particularly so in tobacco and alcohol control efforts and efforts to change dietary patterns and physical activity levels as a means of addressing increases in noncommunicable diseases. To understand the potential impact of pricing policies, it is critical to understand the nature of price elasticities for consumer products. For example, price elasticities are key parameters in models of any food tax or subsidy that aims to quantify health impacts and cost-effectiveness. We detail relevant terms and discuss key issues surrounding price elasticities to inform public health research and intervention studies.
Li, Jiguo
2014-01-01
Signcryption is a useful cryptographic primitive that achieves confidentiality and authentication in an efficient manner. As an extension of signcryption in certificate-based cryptography, certificate-based signcryption preserves the merits of certificate-based cryptography and signcryption simultaneously. In this paper, we present an improved security model of certificate-based signcryption that covers both public key replacement attack and insider security. We show that an existing certificate-based signcryption scheme is insecure in our model. We also propose a new certificate-based signcryption scheme that achieves security against both public key replacement attacks and insider attacks. We prove in the random oracle model that the proposed scheme is chosen-ciphertext secure and existentially unforgeable. Performance analysis shows that the proposed scheme outperforms all the previous certificate-based signcryption schemes in the literature. PMID:24959606
The Development of a Portable Hard Disk Encryption/Decryption System with a MEMS Coded Lock.
Zhang, Weiping; Chen, Wenyuan; Tang, Jian; Xu, Peng; Li, Yibin; Li, Shengyong
2009-01-01
In this paper, a novel portable hard-disk encryption/decryption system with a MEMS coded lock is presented, which can authenticate the user and provide the key for the AES encryption/decryption module. The portable hard-disk encryption/decryption system is composed of the authentication module, the USB portable hard-disk interface card, the ATA protocol command decoder module, the data encryption/decryption module, the cipher key management module, the MEMS coded lock controlling circuit module, the MEMS coded lock and the hard disk. The ATA protocol circuit, the MEMS control circuit and AES encryption/decryption circuit are designed and realized by FPGA(Field Programmable Gate Array). The MEMS coded lock with two couplers and two groups of counter-meshing-gears (CMGs) are fabricated by a LIGA-like process and precision engineering method. The whole prototype was fabricated and tested. The test results show that the user's password could be correctly discriminated by the MEMS coded lock, and the AES encryption module could get the key from the MEMS coded lock. Moreover, the data in the hard-disk could be encrypted or decrypted, and the read-write speed of the dataflow could reach 17 MB/s in Ultra DMA mode.
Photonic encryption : modeling and functional analysis of all optical logic.
Tang, Jason D.; Schroeppel, Richard Crabtree; Robertson, Perry J.
2004-10-01
With the build-out of large transport networks utilizing optical technologies, more and more capacity is being made available. Innovations in Dense Wave Division Multiplexing (DWDM) and the elimination of optical-electrical-optical conversions have brought on advances in communication speeds as we move into 10 Gigabit Ethernet and above. Of course, there is a need to encrypt data on these optical links as the data traverses public and private network backbones. Unfortunately, as the communications infrastructure becomes increasingly optical, advances in encryption (done electronically) have failed to keep up. This project examines the use of optical logic for implementing encryption in the photonic domain to achieve the requisite encryption rates. This paper documents the innovations and advances of work first detailed in 'Photonic Encryption using All Optical Logic,' [1]. A discussion of underlying concepts can be found in SAND2003-4474. In order to realize photonic encryption designs, technology developed for electrical logic circuits must be translated to the photonic regime. This paper examines S-SEED devices and how discrete logic elements can be interconnected and cascaded to form an optical circuit. Because there is no known software that can model these devices at a circuit level, the functionality of S-SEED devices in an optical circuit was modeled in PSpice. PSpice allows modeling of the macro characteristics of the devices in context of a logic element as opposed to device level computational modeling. By representing light intensity as voltage, 'black box' models are generated that accurately represent the intensity response and logic levels in both technologies. By modeling the behavior at the systems level, one can incorporate systems design tools and a simulation environment to aid in the overall functional design. Each black box model takes certain parameters (reflectance, intensity, input response), and models the optical ripple and time delay
Experimental protocol for packaging and encrypting multiple data
NASA Astrophysics Data System (ADS)
Fredy Barrera, John; Trejos, Sorayda; Tebaldi, Myrian; Torroba, Roberto
2013-05-01
We present a novel single optical packaging and encryption (SOPE) procedure for multiple inputs. This procedure is based on a merging of a 2f scheme with a digital holographic technique to achieve efficient handling of multiple data. Through the 2f system with a random phase mask attached in its input plane, and the holographic technique, we obtain each processed input. A posteriori filtering and repositioning protocol on each hologram followed by an addition of all processed data, allows storing these data to form a single package. The final package is digitally multiplied by a second random phase mask acting as an encryption mask. In this way, the final user receives only one encrypted information unit and a single key, instead of a conventional multiple-image collecting method and several keys. Processing of individual images is cast into an optimization problem. The proposed optimization aims to simplify the handling and recovery of images while packing all of them into a single unit. The decoding process does not have the usual cross-talk or noise problems involved in other methods, as filtering and repositioning precedes the encryption step. All data are recovered in just one step at the same time by applying a simple Fourier transform operation and the decoding key. The proposed protocol takes advantage of optical processing and the versatility of the digital format. Experiments have been conducted using a Mach-Zehnder interferometer. An application is subsequently demonstrated to illustrate the feasibility of the SOPE procedure.
Key Data Gaps Regarding the Public Health Issues Associated with Opioid Analgesics
Schmidt, Teresa D.; Haddox, J. David; Nielsen, Alexandra E.; Wakeland, Wayne; Fitzgerald, John
2014-01-01
Most pharmaceutical opioids are used to treat pain and they have been demonstrated to be effective medications for many. Their abuse and misuse pose significant public health concerns in the United States. Research has provided much insight into the prevalence, scope, and drivers of opioid abuse, but a holistic understanding is limited by a lack of available data regarding key aspects of this public health problem. Twelve data gaps were revealed during the creation of a systems-level computer model of medical use, diversion, nonmedical use, and the adverse outcomes associated with opioid analgesics in the United States. Data specific to these gaps would enhance the validity and real-world applications of systems-level models of this public health problem, and would increase understanding of the complex system in which use and abuse occur. This paper provides an overview of these gaps, argues for the importance of closing them, and provides specific recommendations for future data collection efforts. PMID:24554390
Key Data Gaps Regarding the Public Health Issues Associated with Opioid Analgesics.
Schmidt, Teresa D; Haddox, J David; Nielsen, Alexandra E; Wakeland, Wayne; Fitzgerald, John
2015-10-01
Most pharmaceutical opioids are used to treat pain, and they have been demonstrated to be effective medications for many. Their abuse and misuse pose significant public health concerns in the USA. Research has provided much insight into the prevalence, scope, and drivers of opioid abuse, but a holistic understanding is limited by a lack of available data regarding key aspects of this public health problem. Twelve data gaps were revealed during the creation of a systems-level computer model of medical use, diversion, nonmedical use, and the adverse outcomes associated with opioid analgesics in the USA. Data specific to these gaps would enhance the validity and real-world applications of systems-level models of this public health problem and would increase understanding of the complex system in which use and abuse occur. This paper provides an overview of these gaps, argues for the importance of closing them, and provides specific recommendations for future data collection efforts.
NASA Astrophysics Data System (ADS)
Vilardy, Juan M.; Millán, María S.; Pérez-Cabré, Elisabet
2017-02-01
A novel nonlinear image encryption scheme based on a fully phase nonzero-order joint transform correlator architecture (JTC) in the Gyrator domain (GD) is proposed. In this encryption scheme, the two non-overlapping data distributions of the input plane of the JTC are fully encoded in phase and this input plane is transformed using the Gyrator transform (GT); the intensity distribution captured in the GD represents a new definition of the joint Gyrator power distribution (JGPD). The JGPD is modified by two nonlinear operations with the purpose of retrieving the encrypted image, with enhancement of the decrypted signal quality and improvement of the overall security. There are three keys used in the encryption scheme, two random phase masks and the rotation angle of the GT, which are all necessary for a proper decryption. Decryption is highly sensitivity to changes of the rotation angle of the GT as well as to little changes in other parameters or keys. The proposed encryption scheme in the GD still preserves the shift-invariance properties originated in the JTC-based encryption in the Fourier domain. The proposed encryption scheme is more resistant to brute force attacks, chosen-plaintext attacks, known-plaintext attacks, and ciphertext-only attacks, as they have been introduced in the cryptanalysis of the JTC-based encryption system. Numerical results are presented and discussed in order to verify and analyze the feasibility and validity of the novel encryption-decryption scheme.
Testing a Variety of Encryption Technologies
Henson, T J
2001-04-09
Review and test speeds of various encryption technologies using Entrust Software. Multiple encryption algorithms are included in the product. Algorithms tested were IDEA, CAST, DES, and RC2. Test consisted of taking a 7.7 MB Word document file which included complex graphics and timing encryption, decryption and signing. Encryption is discussed in the GIAC Kickstart section: Information Security: The Big Picture--Part VI.
A DES ASIC Suitable for Network Encryption at 10 Gbps and Beyond
Gass, Karl; Pierson, Lyndon G.; Robertson, Perry J.; Wilcox, D. Craig; Witzke, Edward L.
1999-04-30
The Sandia National Laboratories (SNL) Data Encryption Standard (DES) Application Specific Integrated Circuit (ASIC) is the fastest known implementation of the DES algorithm as defined in the Federal Information Processing Standards (FIPS) Publication 46-2. DES is used for protecting data by cryptographic means. The SNL DES ASIC, over 10 times faster than other currently available DES chips, is a high-speed, filly pipelined implementation offering encryption, decryption, unique key input, or algorithm bypassing on each clock cycle. Operating beyond 105 MHz on 64 bit words, this device is capable of data throughputs greater than 6.7 Billion bits per second (tester limited). Simulations predict proper operation up to 9.28 Billion bits per second. In low frequency, low data rate applications, the ASIC consumes less that one milliwatt of power. The device has features for passing control signals synchronized to throughput data. Three SNL DES ASICS may be easily cascaded to provide the much greater security of triple-key, triple-DES.
Securing Information with Complex Optical Encryption Networks
2015-08-11
encryption networks, and to provide effective and reliable solutions for information security. 15. SUBJECT TERMS Optical Encryption...popularization of networking and internet , much research effort is made in the field of information security. Military communication system makes an...objective is to propose the architectures for a number of complex optical encryption networks so as to provide effective and reliable solutions for
Computing on Encrypted Data: Theory and Application
2016-01-01
SUBJECT TERMS Fully Homomorphic Encryption (FHE), Secure Multiparty Computation (SMC), Learning with Errors (LWE), Attribute Based Encryption (ABE...code) NA Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18 662 Table of Contents 1 Summary...FHE and On-the-Fly Multiparty Computation . . . . . . . . . . . . . . . 8 4.1.4 Practical HE: Machine Learning on Encrypted Data
Private genome analysis through homomorphic encryption
2015-01-01
Background The rapid development of genome sequencing technology allows researchers to access large genome datasets. However, outsourcing the data processing o the cloud poses high risks for personal privacy. The aim of this paper is to give a practical solution for this problem using homomorphic encryption. In our approach, all the computations can be performed in an untrusted cloud without requiring the decryption key or any interaction with the data owner, which preserves the privacy of genome data. Methods We present evaluation algorithms for secure computation of the minor allele frequencies and χ2 statistic in a genome-wide association studies setting. We also describe how to privately compute the Hamming distance and approximate Edit distance between encrypted DNA sequences. Finally, we compare performance details of using two practical homomorphic encryption schemes - the BGV scheme by Gentry, Halevi and Smart and the YASHE scheme by Bos, Lauter, Loftus and Naehrig. Results The approach with the YASHE scheme analyzes data from 400 people within about 2 seconds and picks a variant associated with disease from 311 spots. For another task, using the BGV scheme, it took about 65 seconds to securely compute the approximate Edit distance for DNA sequences of size 5K and figure out the differences between them. Conclusions The performance numbers for BGV are better than YASHE when homomorphically evaluating deep circuits (like the Hamming distance algorithm or approximate Edit distance algorithm). On the other hand, it is more efficient to use the YASHE scheme for a low-degree computation, such as minor allele frequencies or χ2 test statistic in a case-control study. PMID:26733152
Encrypting three-dimensional information system based on integral imaging and multiple chaotic maps
NASA Astrophysics Data System (ADS)
Xing, Yan; Wang, Qiong-Hua; Xiong, Zhao-Long; Deng, Huan
2016-02-01
An encrypting three-dimensional (3-D) information system based on integral imaging (II) and multiple chaotic maps is proposed. In the encrypting process, the elemental image array (EIA) which represents spatial and angular information of the real 3-D scene is picked up by a microlens array. Subsequently, R, G, and B color components decomposed by the EIA are encrypted using multiple chaotic maps. Finally, these three encrypted components are interwoven to obtain the cipher information. The decryption process implements the reverse operation of the encryption process for retrieving the high-quality 3-D images. Since the encrypted EIA has the data redundancy property due to II, and all parameters of the pickup part are the secret keys of the encrypting system, the system sensitivity on the changes of the plaintext and secret keys can be significantly improved. Moreover, the algorithm based on multiple chaotic maps can effectively enhance the security. A preliminary experiment is carried out, and the experimental results verify the effectiveness, robustness, and security of the proposed system.
Discrete Logarithms in Finite Fields Some Algorithms for Computing New Public Key Cryptosystem
NASA Astrophysics Data System (ADS)
Trendafilov, Ivan D.; Durcheva, Mariana I.
2010-10-01
Let p be a prime, Fp be a finite field, g be a primitive element of Fp and let h be a nonzero element of Fp. The discrete logarithm problem (DLP) is the problem of finding that an exponent k for which gk≡h (mod p). The well-known problem of computing discrete logarithms has additional importance in recent years due to its applicability in cryptography. Several cryptographic systems would become insecure if an efficient discrete logarithm algorithm were discovered. In this paper are discused some known algorithms in this area. Most public key cryptosystems have been constructed based on abelian groups. Here we introduce how the discrete logarithm problem over a group can be seen as a special instance of an action by an abelian semigroup on finite set. The proposed new public key cryptosystem generalized the semigroup action problem due to Rosenlicht (see [8]) and shows how every semigroup action by an abelian semigroup gives rise to a Diffie-Hellman key exchange.
Double image encryption by using iterative random binary encoding in gyrator domains.
Liu, Zhengjun; Guo, Qing; Xu, Lie; Ahmad, Muhammad Ashfaq; Liu, Shutian
2010-05-24
We propose a double image encryption by using random binary encoding and gyrator transform. Two secret images are first regarded as the real part and imaginary part of complex function. Chaotic map is used for obtaining random binary matrix. The real part and imaginary part of complex function are exchanged under the control of random binary data. An iterative structure composed of the random binary encoding method is designed and employed for enhancing the security of encryption algorithm. The parameters in chaotic map and gyrator transform serve as the keys of this encryption scheme. Some numerical simulations have been made, to demonstrate the performance this algorithm.
A new image encryption algorithm based on logistic chaotic map with varying parameter.
Liu, Lingfeng; Miao, Suoxia
2016-01-01
In this paper, we proposed a new image encryption algorithm based on parameter-varied logistic chaotic map and dynamical algorithm. The parameter-varied logistic map can cure the weaknesses of logistic map and resist the phase space reconstruction attack. We use the parameter-varied logistic map to shuffle the plain image, and then use a dynamical algorithm to encrypt the image. We carry out several experiments, including Histogram analysis, information entropy analysis, sensitivity analysis, key space analysis, correlation analysis and computational complexity to evaluate its performances. The experiment results show that this algorithm is with high security and can be competitive for image encryption.
Automated information extraction of key trial design elements from clinical trial publications.
de Bruijn, Berry; Carini, Simona; Kiritchenko, Svetlana; Martin, Joel; Sim, Ida
2008-11-06
Clinical trials are one of the most valuable sources of scientific evidence for improving the practice of medicine. The Trial Bank project aims to improve structured access to trial findings by including formalized trial information into a knowledge base. Manually extracting trial information from published articles is costly, but automated information extraction techniques can assist. The current study highlights a single architecture to extract a wide array of information elements from full-text publications of randomized clinical trials (RCTs). This architecture combines a text classifier with a weak regular expression matcher. We tested this two-stage architecture on 88 RCT reports from 5 leading medical journals, extracting 23 elements of key trial information such as eligibility rules, sample size, intervention, and outcome names. Results prove this to be a promising avenue to help critical appraisers, systematic reviewers, and curators quickly identify key information elements in published RCT articles.
Evaluating Predicates over Encrypted Data
2008-10-01
attribute-based encryp- tion. In Proceedings of the 2007 IEEE Symposium on Security and Privacy, 2007. 1.2 [3] Dan Boneh and Xavier Boyen. Efficient...selective-ID secure identity based encryption without random oracles. In EUROCRYPT, 2004. 2.1.2, 3.1.3, 4.1.2, 5.1, 5.3.3 [4] Dan Boneh , Xavier Boyen...and Eu-Jin Goh. Hierarchical identity based encryption with constant size ciphertext. In EUROCRYPT, pages 440–456, 2005. 4.1.2, 4.4 [5] Dan Boneh
Suldovsky, Brianne
2016-05-01
Despite mounting criticism, the deficit model remains an integral part of science communication research and practice. In this article, I advance three key factors that contribute to the idea of the public deficit in science communication, including the purpose of science communication, how communication processes and outcomes are conceptualized, and how science and scientific knowledge are defined. Affording science absolute epistemic privilege, I argue, is the most compelling factor contributing to the continued use of the deficit model. In addition, I contend that the deficit model plays a necessary, though not sufficient, role in science communication research and practice. Areas for future research are discussed.
Ensemble of Chaotic and Naive Approaches for Performance Enhancement in Video Encryption.
Chandrasekaran, Jeyamala; Thiruvengadam, S J
2015-01-01
Owing to the growth of high performance network technologies, multimedia applications over the Internet are increasing exponentially. Applications like video conferencing, video-on-demand, and pay-per-view depend upon encryption algorithms for providing confidentiality. Video communication is characterized by distinct features such as large volume, high redundancy between adjacent frames, video codec compliance, syntax compliance, and application specific requirements. Naive approaches for video encryption encrypt the entire video stream with conventional text based cryptographic algorithms. Although naive approaches are the most secure for video encryption, the computational cost associated with them is very high. This research work aims at enhancing the speed of naive approaches through chaos based S-box design. Chaotic equations are popularly known for randomness, extreme sensitivity to initial conditions, and ergodicity. The proposed methodology employs two-dimensional discrete Henon map for (i) generation of dynamic and key-dependent S-box that could be integrated with symmetric algorithms like Blowfish and Data Encryption Standard (DES) and (ii) generation of one-time keys for simple substitution ciphers. The proposed design is tested for randomness, nonlinearity, avalanche effect, bit independence criterion, and key sensitivity. Experimental results confirm that chaos based S-box design and key generation significantly reduce the computational cost of video encryption with no compromise in security.
Optical image encryption based on a joint Fresnel transform correlator with double optical wedges.
Shen, Xueju; Dou, Shuaifeng; Lei, Ming; Chen, Yudan
2016-10-20
An optical cryptosystem based on the joint Fresnel transform correlator (JFTC) with double optical wedges is designed. The designed cryptosystem retains the two major advantages of JTC-based optical cryptosystems. First, the encrypted image is real-valued and therefore is easier to record and transmit. Second, the encryption process is simplified, since it doesn't require accurate alignment of optical elements or the generation of the complex conjugate of the key. Also, the designed optical cryptosystem can produce a decrypted image with higher quality than a JTC-based optical cryptosystem, because the original encrypted image is divided by the Fresnel transform power distribution of the key mask to generate the new encrypted image, which significantly reduces the noise during the decryption process. Simulation results showed that the correlation coefficient of the decrypted image and the original image can reach as large as 0.9819 after denoising and adequately selecting half-central interval a and encrypted image width w. Another improvement relative to JTC-based optical cryptosystems is that the attack resistibility gets enhanced due to the nonlinearity of the encryption process as well as the additional key parameter a, which enlarges the key space.
Ensemble of Chaotic and Naive Approaches for Performance Enhancement in Video Encryption
Chandrasekaran, Jeyamala; Thiruvengadam, S. J.
2015-01-01
Owing to the growth of high performance network technologies, multimedia applications over the Internet are increasing exponentially. Applications like video conferencing, video-on-demand, and pay-per-view depend upon encryption algorithms for providing confidentiality. Video communication is characterized by distinct features such as large volume, high redundancy between adjacent frames, video codec compliance, syntax compliance, and application specific requirements. Naive approaches for video encryption encrypt the entire video stream with conventional text based cryptographic algorithms. Although naive approaches are the most secure for video encryption, the computational cost associated with them is very high. This research work aims at enhancing the speed of naive approaches through chaos based S-box design. Chaotic equations are popularly known for randomness, extreme sensitivity to initial conditions, and ergodicity. The proposed methodology employs two-dimensional discrete Henon map for (i) generation of dynamic and key-dependent S-box that could be integrated with symmetric algorithms like Blowfish and Data Encryption Standard (DES) and (ii) generation of one-time keys for simple substitution ciphers. The proposed design is tested for randomness, nonlinearity, avalanche effect, bit independence criterion, and key sensitivity. Experimental results confirm that chaos based S-box design and key generation significantly reduce the computational cost of video encryption with no compromise in security. PMID:26550603
Enhancement of utilization of encryption engine
Robertson, Robert J.; Witzke, Edward L.
2008-04-22
A method of enhancing throughput of a pipelined encryption/decryption engine for an encryption/decryption process has a predetermined number of stages and provides feedback around the stages (and of such an encryption/decryption engine) by receiving a source datablock for a given stage and encryption/decryption context identifier; indexing according to the encryption/decryption context identifier into a bank of initial variables to retrieve an initial variable for the source datablock; and generating an output datablock from the source datablock and its corresponding initial variable.
Asymmetric multiple-image encryption based on the cascaded fractional Fourier transform
NASA Astrophysics Data System (ADS)
Li, Yanbin; Zhang, Feng; Li, Yuanchao; Tao, Ran
2015-09-01
A multiple-image cryptosystem is proposed based on the cascaded fractional Fourier transform. During an encryption procedure, each of the original images is directly separated into two phase masks. A portion of the masks is subsequently modulated into an interim mask, which is encrypted into the ciphertext image; the others are used as the encryption keys. Using phase truncation in the fractional Fourier domain, one can use an asymmetric cryptosystem to produce a real-valued noise-like ciphertext, while a legal user can reconstruct all of the original images using a different group of phase masks. The encryption key is an indivisible part of the corresponding original image and is still useful during decryption. The proposed system has high resistance to various potential attacks, including the chosen-plaintext attack. Numerical simulations also demonstrate the security and feasibility of the proposed scheme.
Chang, Hsuan T; Shui, J-W; Lin, K-P
2017-02-01
In this paper, a joint multiple-image encryption and multiplexing system, which utilizes both the nonnegative matrix factorization (NMF) scheme and digital holography, is proposed. A number of images are transformed into noise-like digital holograms, which are then decomposed into a defined number of basis images and a corresponding weighting matrix using the NMF scheme. The determined basis images are similar to the digital holograms and appear as noise-like patterns, which are then stored as encrypted data and serve as the lock in an encryption system. On the other hand, the column vectors in the weighting matrix serve as the keys for the corresponding plain images or the addresses of the multiplexed images. Both the increased uniformity of the column weighting factors and the parameters used in the digital holography enhance the security of the distributed keys. The experimental results show that the proposed method can successfully perform multiple-image encryption with high-level security.
Quantization-based semi-fragile public-key watermarking for secure image authentication
NASA Astrophysics Data System (ADS)
Schlauweg, Mathias; Proefrock, Dima; Palfner, Torsten; Mueller, Erika
2005-09-01
Authentication watermarking approaches can be classified into two kinds: fragile and semi-fragile. In contrast to the latter one, fragile watermarking does not tolerate modifications of any single bit of the watermarked data. Since the transmission of digital data often requires lossy compression, an authentication system should accept non-malicious modifications such as JPEG compression. Semi-fragile techniques aim to discriminate malicious manipulations from admissible manipulations. In our approach, we extract image content dependent information, which is hashed afterwards and encrypted using secure methods known from the classical cryptography. The image data is partitioned into nonoverlapping 4x4 pixel blocks in the spatial domain. The mean values of these blocks form n-dimensional vectors, which are quantized to the nearest lattice point neighbours. Based on the changed vector values, a hash is calculated and asymmetrically encrypted, resulting in a digital signature. Traditional dual subspace approaches divide the signal space into a region for signature generation and a region for signature embedding. To ensure the security of the whole image, we join the two subspaces. The vectors, where to embed the bits using quantization-based data hiding techniques, are predistorted and also used for the signature generation. Our scheme applies error correction coding to gain the robustness of the embedded signature to non-malicious distortions. A second quantization run finally embeds the signature.
Secure Obfuscation for Encrypted Group Signatures
Fan, Hongfei; Liu, Qin
2015-01-01
In recent years, group signature techniques are widely used in constructing privacy-preserving security schemes for various information systems. However, conventional techniques keep the schemes secure only in normal black-box attack contexts. In other words, these schemes suppose that (the implementation of) the group signature generation algorithm is running in a platform that is perfectly protected from various intrusions and attacks. As a complementary to existing studies, how to generate group signatures securely in a more austere security context, such as a white-box attack context, is studied in this paper. We use obfuscation as an approach to acquire a higher level of security. Concretely, we introduce a special group signature functionality-an encrypted group signature, and then provide an obfuscator for the proposed functionality. A series of new security notions for both the functionality and its obfuscator has been introduced. The most important one is the average-case secure virtual black-box property w.r.t. dependent oracles and restricted dependent oracles which captures the requirement of protecting the output of the proposed obfuscator against collision attacks from group members. The security notions fit for many other specialized obfuscators, such as obfuscators for identity-based signatures, threshold signatures and key-insulated signatures. Finally, the correctness and security of the proposed obfuscator have been proven. Thereby, the obfuscated encrypted group signature functionality can be applied to variants of privacy-preserving security schemes and enhance the security level of these schemes. PMID:26167686
Symmetric weak ternary quantum homomorphic encryption schemes
NASA Astrophysics Data System (ADS)
Wang, Yuqi; She, Kun; Luo, Qingbin; Yang, Fan; Zhao, Chao
2016-03-01
Based on a ternary quantum logic circuit, four symmetric weak ternary quantum homomorphic encryption (QHE) schemes were proposed. First, for a one-qutrit rotation gate, a QHE scheme was constructed. Second, in view of the synthesis of a general 3 × 3 unitary transformation, another one-qutrit QHE scheme was proposed. Third, according to the one-qutrit scheme, the two-qutrit QHE scheme about generalized controlled X (GCX(m,n)) gate was constructed and further generalized to the n-qutrit unitary matrix case. Finally, the security of these schemes was analyzed in two respects. It can be concluded that the attacker can correctly guess the encryption key with a maximum probability pk = 1/33n, thus it can better protect the privacy of users’ data. Moreover, these schemes can be well integrated into the future quantum remote server architecture, and thus the computational security of the users’ private quantum information can be well protected in a distributed computing environment.
Novel Authentication of Monitoring Data Through the use of Secret and Public Cryptographic Keys
Benz, Jacob M.; Tolk, Keith; Tanner, Jennifer E.
2014-07-21
The Office of Nuclear Verification (ONV) is supporting the development of a piece of equipment to provide data authentication and protection for a suite of monitoring sensors as part of a larger effort to create an arms control technology toolkit. This device, currently called the Red Box, leverages the strengths of both secret and public cryptographic keys to authenticate, digitally sign, and pass along monitoring data to allow for host review, and redaction if necessary, without the loss of confidence in the authenticity of the data by the monitoring party. The design of the Red Box will allow for the addition and removal of monitoring equipment and can also verify that the data was collected by authentic monitoring equipment prior to signing the data and sending it to the host and for review. The host will then forward the data to the monitor for review and inspection. This paper will highlight the progress to date of the Red Box development, and will explain the novel method of leveraging both symmetric and asymmetric (secret and public key) cryptography to authenticate data within a warhead monitoring regime.
Global trade, public health, and health services: stakeholders' constructions of the key issues.
Waitzkin, Howard; Jasso-Aguilar, Rebeca; Landwehr, Angela; Mountain, Carolyn
2005-09-01
Focusing mainly on the United States and Latin America, we aimed to identify the constructions of social reality held by the major stakeholders participating in policy debates about global trade, public health, and health services. In a multi-method, qualitative design, we used three sources of data: research and archival literature, 1980-2004; interviews with key informants who represented major organizations participating in these debates, 2002-2004; and organizational reports, 1980-2004. We targeted several types of organizations: government agencies, international financial institutions (IFIs) and trade organizations, international health organizations, multinational corporations, and advocacy groups. Many governments in Latin America define health as a right and health services as a public good. Thus, the government bears responsibility for that right. In contrast, the US government's philosophy of free trade and promoting a market economy assumes that by expanding the private sector, improved economic conditions will improve overall health with a minimum government provision of health care. US government agencies also view promotion of global health as a means to serve US interests. IFIs have emphasized reforms that include reduction and privatization of public sector services. International health organizations have tended to adopt the policy perspectives of IFIs and trade organizations. Advocacy groups have emphasized the deleterious effects of international trade agreements on public health and health services. Organizational stakeholders hold widely divergent constructions of reality regarding trade, public health, and health services. Social constructions concerning trade and health reflect broad ideologies concerning the impacts of market processes. Such constructions manifest features of "creed," regarding the role of the market in advancing human purposes and meeting human needs. Differences in constructions of trade and health constrain policies to
a Novel Algorithm for Image Encryption Based on Couple Chaotic Systems
NASA Astrophysics Data System (ADS)
Wang, Xing-Yuan; Wang, Tian
2012-12-01
In this paper, an image encryption algorithm based on couple multiple chaotic systems is presented. It made the one-dimensional Coupled Map Lattice (CML) formed by Skew Tent map as spatiotemporal chaotic system and made its output sequence as the initial value of logistic and meanwhile did iterative of specific times to get the final key sequence, and then did XOR operations with corresponding pixels to finish the encryption. Numerical analysis expresses that this algorithm has large enough space and high security.
Distributed Factorization Computation on Multiple Volunteered Mobile Resource to Break RSA Key
NASA Astrophysics Data System (ADS)
Jaya, I.; Hardi, S. M.; Tarigan, J. T.; Zamzami, E. M.; Sihombing, P.
2017-01-01
Similar to common asymmeric encryption, RSA can be cracked by usmg a series mathematical calculation. The private key used to decrypt the massage can be computed using the public key. However, finding the private key may require a massive amount of calculation. In this paper, we propose a method to perform a distributed computing to calculate RSA’s private key. The proposed method uses multiple volunteered mobile devices to contribute during the calculation process. Our objective is to demonstrate how the use of volunteered computing on mobile devices may be a feasible option to reduce the time required to break a weak RSA encryption and observe the behavior and running time of the application on mobile devices.
Wang, Xiaogang; Zhao, Daomu; Chen, Yixiang
2014-08-10
We present a study about information disclosure in phase-truncation-based cryptosystems. The main information of the original image to be encoded can be obtained by using a decryption key in the worst case. The problem cannot be thoroughly solved by imaginary part truncating, keeping the encryption keys as private keys, or applying different phase keys for different plaintexts during each encryption process as well as the phase modulation in the frequency domain. In order to eliminate the risk of unintended information disclosure, we further propose a nonlinear spatial and spectral encoding technique using a random amplitude mask (RAM). The encryption process involving two security layers can be fully controlled by a RAM. The spatial encoding of the plaintext images and the simultaneous encryption of the plaintext images and the encryption key greatly enhance the security of system, avoiding several attacks that have cracked the phase-truncation-based cryptosystems. Besides, the hybrid encryption system retains the advantage of a trap door one-way function of phase truncation. Numerical results have demonstrated the feasibility and effectiveness of the proposed encryption algorithm.
A symmetrical image encryption scheme in wavelet and time domain
NASA Astrophysics Data System (ADS)
Luo, Yuling; Du, Minghui; Liu, Junxiu
2015-02-01
There has been an increasing concern for effective storages and secure transactions of multimedia information over the Internet. Then a great variety of encryption schemes have been proposed to ensure the information security while transmitting, but most of current approaches are designed to diffuse the data only in spatial domain which result in reducing storage efficiency. A lightweight image encryption strategy based on chaos is proposed in this paper. The encryption process is designed in transform domain. The original image is decomposed into approximation and detail components using integer wavelet transform (IWT); then as the more important component of the image, the approximation coefficients are diffused by secret keys generated from a spatiotemporal chaotic system followed by inverse IWT to construct the diffused image; finally a plain permutation is performed for diffusion image by the Logistic mapping in order to reduce the correlation between adjacent pixels further. Experimental results and performance analysis demonstrate the proposed scheme is an efficient, secure and robust encryption mechanism and it realizes effective coding compression to satisfy desirable storage.
Volumetric Light-field Encryption at the Microscopic Scale.
Li, Haoyu; Guo, Changliang; Muniraj, Inbarasan; Schroeder, Bryce C; Sheridan, John T; Jia, Shu
2017-01-06
We report a light-field based method that allows the optical encryption of three-dimensional (3D) volumetric information at the microscopic scale in a single 2D light-field image. The system consists of a microlens array and an array of random phase/amplitude masks. The method utilizes a wave optics model to account for the dominant diffraction effect at this new scale, and the system point-spread function (PSF) serves as the key for encryption and decryption. We successfully developed and demonstrated a deconvolution algorithm to retrieve both spatially multiplexed discrete data and continuous volumetric data from 2D light-field images. Showing that the method is practical for data transmission and storage, we obtained a faithful reconstruction of the 3D volumetric information from a digital copy of the encrypted light-field image. The method represents a new level of optical encryption, paving the way for broad industrial and biomedical applications in processing and securing 3D data at the microscopic scale.
Volumetric Light-field Encryption at the Microscopic Scale
Li, Haoyu; Guo, Changliang; Muniraj, Inbarasan; Schroeder, Bryce C.; Sheridan, John T.; Jia, Shu
2017-01-01
We report a light-field based method that allows the optical encryption of three-dimensional (3D) volumetric information at the microscopic scale in a single 2D light-field image. The system consists of a microlens array and an array of random phase/amplitude masks. The method utilizes a wave optics model to account for the dominant diffraction effect at this new scale, and the system point-spread function (PSF) serves as the key for encryption and decryption. We successfully developed and demonstrated a deconvolution algorithm to retrieve both spatially multiplexed discrete data and continuous volumetric data from 2D light-field images. Showing that the method is practical for data transmission and storage, we obtained a faithful reconstruction of the 3D volumetric information from a digital copy of the encrypted light-field image. The method represents a new level of optical encryption, paving the way for broad industrial and biomedical applications in processing and securing 3D data at the microscopic scale. PMID:28059149
Masking property of quantum random cipher with phase mask encryption
NASA Astrophysics Data System (ADS)
Sohma, Masaki; Hirota, Osamu
2014-10-01
The security analysis of physical encryption protocol based on coherent pulse position modulation (CPPM) originated by Yuen is one of the most interesting topics in the study of cryptosystem with a security level beyond the Shannon limit. Although the implementation of CPPM scheme has certain difficulty, several methods have been proposed recently. This paper deals with the CPPM encryption in terms of symplectic transformation, which includes a phase mask encryption as a special example, and formulates a unified security analysis for such encryption schemes. Specifically, we give a lower bound of Eve's symbol error probability using reliability function theory to ensure that our proposed system exceeds the Shannon limit. Then we assume the secret key is given to Eve after her heterodyne measurement. Since this assumption means that Eve has a great advantage in the sense of the conventional cryptography, the lower bound of her error indeed ensures the security level beyond the Shannon limit. In addition, we show some numerical examples of the security performance.
Volumetric Light-field Encryption at the Microscopic Scale
NASA Astrophysics Data System (ADS)
Li, Haoyu; Guo, Changliang; Muniraj, Inbarasan; Schroeder, Bryce C.; Sheridan, John T.; Jia, Shu
2017-01-01
We report a light-field based method that allows the optical encryption of three-dimensional (3D) volumetric information at the microscopic scale in a single 2D light-field image. The system consists of a microlens array and an array of random phase/amplitude masks. The method utilizes a wave optics model to account for the dominant diffraction effect at this new scale, and the system point-spread function (PSF) serves as the key for encryption and decryption. We successfully developed and demonstrated a deconvolution algorithm to retrieve both spatially multiplexed discrete data and continuous volumetric data from 2D light-field images. Showing that the method is practical for data transmission and storage, we obtained a faithful reconstruction of the 3D volumetric information from a digital copy of the encrypted light-field image. The method represents a new level of optical encryption, paving the way for broad industrial and biomedical applications in processing and securing 3D data at the microscopic scale.
Encryption for Remote Control via Internet or Intranet
NASA Technical Reports Server (NTRS)
Lineberger, Lewis
2005-01-01
A data-communication protocol has been devised to enable secure, reliable remote control of processes and equipment via a collision-based network, while using minimal bandwidth and computation. The network could be the Internet or an intranet. Control is made secure by use of both a password and a dynamic key, which is sent transparently to a remote user by the controlled computer (that is, the computer, located at the site of the equipment or process to be controlled, that exerts direct control over the process). The protocol functions in the presence of network latency, overcomes errors caused by missed dynamic keys, and defeats attempts by unauthorized remote users to gain control. The protocol is not suitable for real-time control, but is well suited for applications in which control latencies up to about 0.5 second are acceptable. The encryption scheme involves the use of both a dynamic and a private key, without any additional overhead that would degrade performance. The dynamic key is embedded in the equipment- or process-monitor data packets sent out by the controlled computer: in other words, the dynamic key is a subset of the data in each such data packet. The controlled computer maintains a history of the last 3 to 5 data packets for use in decrypting incoming control commands. In addition, the controlled computer records a private key (password) that is given to the remote computer. The encrypted incoming command is permuted by both the dynamic and private key. A person who records the command data in a given packet for hostile purposes cannot use that packet after the public key expires (typically within 3 seconds). Even a person in possession of an unauthorized copy of the command/remote-display software cannot use that software in the absence of the password. The use of a dynamic key embedded in the outgoing data makes the central-processing unit overhead very small. The use of a National Instruments DataSocket(TradeMark) (or equivalent) protocol or
NASA Astrophysics Data System (ADS)
Belazi, Akram; Abd El-Latif, Ahmed A.; Diaconu, Adrian-Viorel; Rhouma, Rhouma; Belghith, Safya
2017-01-01
In this paper, a new chaos-based partial image encryption scheme based on Substitution-boxes (S-box) constructed by chaotic system and Linear Fractional Transform (LFT) is proposed. It encrypts only the requisite parts of the sensitive information in Lifting-Wavelet Transform (LWT) frequency domain based on hybrid of chaotic maps and a new S-box. In the proposed encryption scheme, the characteristics of confusion and diffusion are accomplished in three phases: block permutation, substitution, and diffusion. Then, we used dynamic keys instead of fixed keys used in other approaches, to control the encryption process and make any attack impossible. The new S-box was constructed by mixing of chaotic map and LFT to insure the high confidentiality in the inner encryption of the proposed approach. In addition, the hybrid compound of S-box and chaotic systems strengthened the whole encryption performance and enlarged the key space required to resist the brute force attacks. Extensive experiments were conducted to evaluate the security and efficiency of the proposed approach. In comparison with previous schemes, the proposed cryptosystem scheme showed high performances and great potential for prominent prevalence in cryptographic applications.
Encryption of color images using MSVD in DCST domain
NASA Astrophysics Data System (ADS)
Kumar, Manoj; Vaish, Ankita
2017-01-01
In this paper, a new image encryption and decryption algorithm based on Multiresolution Singular Value Decomposition (MSVD) and Discrete Cosine Stockwell Transform (DCST) is proposed. An original image is first transformed in DCST domain and then decomposed into four subbands using MSVD, all the four subbands are further decomposed into four subimages according to their indexing and masked by the parameters generated by MSVD. We have used number of bands of DCST, arrangement of MSVD subbands, arrangement of various subimages obtained from MSVD subbands, values and arrangement of a 4×4 matrix generated by MSVD and the arrangement of masked subimages as encryption and decryption keys. To ensure the correct decryption of encrypted image, it is indeed necessary to have correct knowledge of all keys in correct order along with their exact values. If all the keys are correct but a single key is wrong even though it would be almost impossible to guess the original image. The efficiency of proposed algorithm is evaluated by comparing it with some recent published works and it is evident from the experimental results and analysis that the proposed algorithm can transmit the images more securely and efficiently over the network.
15 CFR 740.17 - Encryption commodities, software and technology (ENC).
Code of Federal Regulations, 2010 CFR
2010-01-01
...: for symmetric algorithms with key lengths not exceeding 80 bits; for asymmetric algorithms with key lengths not exceeding 1,024 bits; and for elliptic curve algorithms with key lengths not exceeding 160... symmetric algorithms: (A) Aggregate encrypted WAN, MAN, VPN or backhaul throughput (includes...
Quantum-noise randomized data encryption for wavelength-division-multiplexed fiber-optic networks
Corndorf, Eric; Liang Chuang; Kanter, Gregory S.; Kumar, Prem; Yuen, Horace P.
2005-06-15
We demonstrate high-rate randomized data-encryption through optical fibers using the inherent quantum-measurement noise of coherent states of light. Specifically, we demonstrate 650 Mbit/s data encryption through a 10 Gbit/s data-bearing, in-line amplified 200-km-long line. In our protocol, legitimate users (who share a short secret key) communicate using an M-ry signal set while an attacker (who does not share the secret key) is forced to contend with the fundamental and irreducible quantum-measurement noise of coherent states. Implementations of our protocol using both polarization-encoded signal sets as well as polarization-insensitive phase-keyed signal sets are experimentally and theoretically evaluated. Different from the performance criteria for the cryptographic objective of key generation (quantum key-generation), one possible set of performance criteria for the cryptographic objective of data encryption is established and carefully considered.
Secure Data Aggregation with Fully Homomorphic Encryption in Large-Scale Wireless Sensor Networks
Li, Xing; Chen, Dexin; Li, Chunyan; Wang, Liangmin
2015-01-01
With the rapid development of wireless communication technology, sensor technology, information acquisition and processing technology, sensor networks will finally have a deep influence on all aspects of people’s lives. The battery resources of sensor nodes should be managed efficiently in order to prolong network lifetime in large-scale wireless sensor networks (LWSNs). Data aggregation represents an important method to remove redundancy as well as unnecessary data transmission and hence cut down the energy used in communication. As sensor nodes are deployed in hostile environments, the security of the sensitive information such as confidentiality and integrity should be considered. This paper proposes Fully homomorphic Encryption based Secure data Aggregation (FESA) in LWSNs which can protect end-to-end data confidentiality and support arbitrary aggregation operations over encrypted data. In addition, by utilizing message authentication codes (MACs), this scheme can also verify data integrity during data aggregation and forwarding processes so that false data can be detected as early as possible. Although the FHE increase the computation overhead due to its large public key size, simulation results show that it is implementable in LWSNs and performs well. Compared with other protocols, the transmitted data and network overhead are reduced in our scheme. PMID:26151208
Secure Data Aggregation with Fully Homomorphic Encryption in Large-Scale Wireless Sensor Networks.
Li, Xing; Chen, Dexin; Li, Chunyan; Wang, Liangmin
2015-07-03
With the rapid development of wireless communication technology, sensor technology, information acquisition and processing technology, sensor networks will finally have a deep influence on all aspects of people's lives. The battery resources of sensor nodes should be managed efficiently in order to prolong network lifetime in large-scale wireless sensor networks (LWSNs). Data aggregation represents an important method to remove redundancy as well as unnecessary data transmission and hence cut down the energy used in communication. As sensor nodes are deployed in hostile environments, the security of the sensitive information such as confidentiality and integrity should be considered. This paper proposes Fully homomorphic Encryption based Secure data Aggregation (FESA) in LWSNs which can protect end-to-end data confidentiality and support arbitrary aggregation operations over encrypted data. In addition, by utilizing message authentication codes (MACs), this scheme can also verify data integrity during data aggregation and forwarding processes so that false data can be detected as early as possible. Although the FHE increase the computation overhead due to its large public key size, simulation results show that it is implementable in LWSNs and performs well. Compared with other protocols, the transmitted data and network overhead are reduced in our scheme.
Takeda, Hiroshi; Matsumura, Yasushi; Nakagawa, Katsuhiko; Teratani, Tadamasa; Qiyan, Zhang; Kusuoka, Hideo; Matsuoka, Masami
2004-01-01
To share healthcare information and to promote cooperation among healthcare providers and customers (patients) under computerized network environment, a non-profit organization (NPO), named as OCHIS, was established at Osaka, Japan in 2003. Since security and confidentiality issues on the Internet have been major concerns in the OCHIS, the system has been based on healthcare public key infrastructure (HPKI), and found that there remained problems to be solved technically and operationally. An experimental study was conducted to elucidate the central and the local function in terms of a registration authority and a time stamp authority by contracting with the Ministry of Economics and Trading Industries in 2003. This paper describes the experimental design with NPO and the results of the study concerning message security and HPKI. The developed system has been operated practically in Osaka urban area.
Modular multiplication in GF(p) for public-key cryptography
NASA Astrophysics Data System (ADS)
Olszyna, Jakub
Modular multiplication forms the basis of modular exponentiation which is the core operation of the RSA cryptosystem. It is also present in many other cryptographic algorithms including those based on ECC and HECC. Hence, an efficient implementation of PKC relies on efficient implementation of modular multiplication. The paper presents a survey of most common algorithms for modular multiplication along with hardware architectures especially suitable for cryptographic applications in energy constrained environments. The motivation for studying low-power and areaefficient modular multiplication algorithms comes from enabling public-key security for ultra-low power devices that can perform under constrained environments like wireless sensor networks. Serial architectures for GF(p) are analyzed and presented. Finally proposed architectures are verified and compared according to the amount of power dissipated throughout the operation.
The construction of a public key infrastructure for healthcare information networks in Japan.
Sakamoto, N
2001-01-01
The digital signature is a key technology in the forthcoming Internet society for electronic healthcare as well as for electronic commerce. Efficient exchanges of authorized information with a digital signature in healthcare information networks require a construction of a public key infrastructure (PKI). In order to introduce a PKI to healthcare information networks in Japan, we proposed a development of a user authentication system based on a PKI for user management, user authentication and privilege management of healthcare information systems. In this paper, we describe the design of the user authentication system and its implementation. The user authentication system provides a certification authority service and a privilege management service while it is comprised of a user authentication client and user authentication serves. It is designed on a basis of an X.509 PKI and is implemented with using OpenSSL and OpenLDAP. It was incorporated into the financial information management system for the national university hospitals and has been successfully working for about one year. The hospitals plan to use it as a user authentication method for their whole healthcare information systems. One implementation of the system is free to the national university hospitals with permission of the Japanese Ministry of Education, Culture, Sports, Science and Technology. Another implementation is open to the other healthcare institutes by support of the Medical Information System Development Center (MEDIS-DC). We are moving forward to a nation-wide construction of a PKI for healthcare information networks based on it.
Mapping the key issues shaping the landscape of global public health.
Ager, Alastair; Yu, Gary; Hermosilla, Sabrina
2012-01-01
A survey of global health experts attending an invited meeting provided a means to map key issues perceived to be shaping emerging global public health agendas. Eighty-five participants proposed three major issues likely to have the most significant impact on the field of global health in the coming years. Six raters grouped the resultant items, with multi-dimensional scaling (MDS) analysis producing a composite two-dimensional map depicting the overall patterning of items. Thematic clusters were incorporated within four major domains: changing health and prevention needs (15% of items), globalisation and global health governance (33% of items), transforming health systems (30% of items) and innovations in science and technology (7% of items). The remaining 15% of items addressed forms of environmental change. The distribution of items across domains was not significantly influenced by the current professional role of participants, their current location in the 'global north' or 'global south' or their region of focus (although the latter approached threshold significance). The constraints on interpretation imposed by the biases influencing participation in the survey are noted. However, the exercise suggests the potential for coherently defining shared agendas for diverse stakeholders to address emerging priorities. The closer integration of environmental concerns with other global public issues is clearly warranted.
Optical image encryption based on compressive sensing and chaos in the fractional Fourier domain
NASA Astrophysics Data System (ADS)
Liu, Xingbin; Mei, Wenbo; Du, Huiqian
2014-11-01
We propose a novel image encryption algorithm based on compressive sensing (CS) and chaos in the fractional Fourier domain. The original image is dimensionality reduction measured using CS. The measured values are then encrypted using chaotic-based double-random-phase encoding technique in the fractional Fourier transform domain. The measurement matrix and the random-phase masks used in the encryption process are formed from pseudo-random sequences generated by the chaotic map. In this proposed algorithm, the final result is compressed and encrypted. The proposed cryptosystem decreases the volume of data to be transmitted and simplifies the keys for distribution simultaneously. Numerical experiments verify the validity and security of the proposed algorithm.
NASA Astrophysics Data System (ADS)
Wang, Xiaogang; Zhao, Daomu
2012-10-01
We propose an optoelectronic image encryption and decryption technique based on coherent superposition principle and digital holography. With the help of a chaotic random phase mask (CRPM) that is generated by using logistic map, a real-valued primary image is encoded into a phase-only version and then recorded as an encoded hologram. As for multiple-image encryption, only one digital hologram is to be transmitted as the encrypted result by using the multiplexing technique changing the reference wave angle. The bifurcation parameters, the initial values for the logistic maps, the number of the removed elements and the reference wave parameters are kept and transmitted as private keys. Both the encryption and decryption processes can be implemented in opto-digital manner or fully digital manner. Simulation results are given for testing the feasibility of the proposed approach.
Dual-channel in-line digital holographic double random phase encryption.
Das, Bhargab; Yelleswarapu, Chandra S; Rao, D V G L N
2012-10-01
We present a robust encryption method for the encoding of 2D/3D objects using digital holography and virtual optics. Using our recently developed dual-plane in-line digital holography technique, two in-line digital holograms are recorded at two different planes and are encrypted using two different double random phase encryption configurations, independently. The process of using two mutually exclusive encryption channels makes the system more robust against attacks since both the channels should be decrypted accurately in order to get a recognizable reconstruction. Results show that the reconstructed object is unrecognizable even when the portion of the correct phase keys used during decryption is close to 75%. The system is verified against blind decryptions by evaluating the SNR and MSE. Validation of the proposed method and sensitivities of the associated parameters are quantitatively analyzed and illustrated.
Multiple-image encryption scheme based on cascaded fractional Fourier transform.
Kong, Dezhao; Shen, Xueju; Xu, Qinzu; Xin, Wang; Guo, Haiqiong
2013-04-20
A multiple-image encryption scheme based on cascaded fractional Fourier transform is proposed. In the scheme, images are successively coded into the amplitude and phase of the input by cascading stages, which ends up with an encrypted image and a series of keys. The scheme takes full advantage of multikeys and the cascaded relationships of all stages, and it not only realizes image encryption but also achieves higher safety and more diverse applications. So multiuser authentication and hierarchical encryption are achieved. Numerical simulation verifies the feasibility of the method and demonstrates the security of the scheme and decryption characteristics. Finally, flexibility and variability of the scheme in application are discussed, and the simple photoelectric mixed devices to realize the scheme are proposed.
Double random phase encryption scheme to multiplex and simultaneous encode multiple images.
Alfalou, Ayman; Mansour, Ali
2009-11-01
Here we present a new approach of multiplexing and simultaneous encoding of target images. Our approach can enhance the encryption level of a classical double random phase (DRP) encryption system by adding a supplementary security layer. The new approach can be divided into two security layers. The first layer is called the multiplexing level, which consists in using iterative Fourier transformations along with several encryption key images. These latter can be a set of biometric images. At the second layer, we use a classical DRP system. The two layers enable us to encode several target images (multi-encryption) and to reduce, at the same time, the requested decoded information (transmitted or storage information).
NASA Astrophysics Data System (ADS)
Zhong, Shenlu; Li, Mengjiao; Tang, Xiajie; He, Weiqing; Wang, Xiaogang
2017-01-01
A novel optical information verification and encryption method is proposed based on inference principle and phase retrieval with sparsity constraints. In this method, a target image is encrypted into two phase-only masks (POMs), which comprise sparse phase data used for verification. Both of the two POMs need to be authenticated before being applied for decrypting. The target image can be optically reconstructed when the two authenticated POMs are Fourier transformed and convolved by the correct decryption key, which is also generated in encryption process. No holographic scheme is involved in the proposed optical verification and encryption system and there is also no problem of information disclosure in the two authenticable POMs. Numerical simulation results demonstrate the validity and good performance of this new proposed method.
Analysis of common attacks in public-key cryptosystems based on low-density parity-check codes
NASA Astrophysics Data System (ADS)
Skantzos, N. S.; Saad, D.; Kabashima, Y.
2003-11-01
We analyze the security and reliability of a recently proposed class of public-key cryptosystems against attacks by unauthorized parties who have acquired partial knowledge of one or more of the private key components and/or of the plaintext. Phase diagrams are presented, showing critical partial knowledge levels required for unauthorized decryption.
ERIC Educational Resources Information Center
Young, Charles Keith
2010-01-01
Owing to the significant structural changes that have occurred in the global marketplace over the past 2 decades, a corresponding increase of public-private partnerships have been established among the business sector, local governments, and public community colleges. This qualitative project sought to identify and substantiate key elements that…
Butterfly Encryption Scheme for Resource-Constrained Wireless Networks †
Sampangi, Raghav V.; Sampalli, Srinivas
2015-01-01
Resource-constrained wireless networks are emerging networks such as Radio Frequency Identification (RFID) and Wireless Body Area Networks (WBAN) that might have restrictions on the available resources and the computations that can be performed. These emerging technologies are increasing in popularity, particularly in defence, anti-counterfeiting, logistics and medical applications, and in consumer applications with growing popularity of the Internet of Things. With communication over wireless channels, it is essential to focus attention on securing data. In this paper, we present an encryption scheme called Butterfly encryption scheme. We first discuss a seed update mechanism for pseudorandom number generators (PRNG), and employ this technique to generate keys and authentication parameters for resource-constrained wireless networks. Our scheme is lightweight, as in it requires less resource when implemented and offers high security through increased unpredictability, owing to continuously changing parameters. Our work focuses on accomplishing high security through simplicity and reuse. We evaluate our encryption scheme using simulation, key similarity assessment, key sequence randomness assessment, protocol analysis and security analysis. PMID:26389899
Butterfly Encryption Scheme for Resource-Constrained Wireless Networks.
Sampangi, Raghav V; Sampalli, Srinivas
2015-09-15
Resource-constrained wireless networks are emerging networks such as Radio Frequency Identification (RFID) and Wireless Body Area Networks (WBAN) that might have restrictions on the available resources and the computations that can be performed. These emerging technologies are increasing in popularity, particularly in defence, anti-counterfeiting, logistics and medical applications, and in consumer applications with growing popularity of the Internet of Things. With communication over wireless channels, it is essential to focus attention on securing data. In this paper, we present an encryption scheme called Butterfly encryption scheme. We first discuss a seed update mechanism for pseudorandom number generators (PRNG), and employ this technique to generate keys and authentication parameters for resource-constrained wireless networks. Our scheme is lightweight, as in it requires less resource when implemented and offers high security through increased unpredictability, owing to continuously changing parameters. Our work focuses on accomplishing high security through simplicity and reuse. We evaluate our encryption scheme using simulation, key similarity assessment, key sequence randomness assessment, protocol analysis and security analysis.
Fault tolerant channel-encrypting quantum dialogue against collective noise
NASA Astrophysics Data System (ADS)
Ye, TianYu
2015-04-01
In this paper, two fault tolerant channel-encrypting quantum dialogue (QD) protocols against collective noise are presented. One is against collective-dephasing noise, while the other is against collective-rotation noise. The decoherent-free states, each of which is composed of two physical qubits, act as traveling states combating collective noise. Einstein-Podolsky-Rosen pairs, which play the role of private quantum key, are securely shared between two participants over a collective-noise channel in advance. Through encryption and decryption with private quantum key, the initial state of each traveling two-photon logical qubit is privately shared between two participants. Due to quantum encryption sharing of the initial state of each traveling logical qubit, the issue of information leakage is overcome. The private quantum key can be repeatedly used after rotation as long as the rotation angle is properly chosen, making quantum resource economized. As a result, their information-theoretical efficiency is nearly up to 66.7%. The proposed QD protocols only need single-photon measurements rather than two-photon joint measurements for quantum measurements. Security analysis shows that an eavesdropper cannot obtain anything useful about secret messages during the dialogue process without being discovered. Furthermore, the proposed QD protocols can be implemented with current techniques in experiment.
An enhanced sub-image encryption method
NASA Astrophysics Data System (ADS)
Wang, Xing-Yuan; Zhang, Ying-Qian; Liu, Lin-Tao
2016-11-01
Recently a parallel sub-image encryption method is proposed by Mirzaei et al., which is based on a total shuffling and parallel encryption algorithm. In this paper, we firstly show that the method can be attacked by chosen plaintext attack and then propose an enhanced sub-image algorithm, which can completely resist the chosen plaintext attack. Moreover, our improved algorithm can reduce the encryption time dramatically. The experimental results also prove that the improved encryption algorithm is secure enough. So the improved method can be used in image transmission system.
Novel Image Encryption Scheme Based on Chebyshev Polynomial and Duffing Map
2014-01-01
We present a novel image encryption algorithm using Chebyshev polynomial based on permutation and substitution and Duffing map based on substitution. Comprehensive security analysis has been performed on the designed scheme using key space analysis, visual testing, histogram analysis, information entropy calculation, correlation coefficient analysis, differential analysis, key sensitivity test, and speed test. The study demonstrates that the proposed image encryption algorithm shows advantages of more than 10113 key space and desirable level of security based on the good statistical results and theoretical arguments. PMID:25143970
Deng, Xiaopeng; Zhao, Daomu
2011-11-01
A single-channel color image encryption is proposed based on the modified Gerchberg-Saxton algorithm (MGSA) and mutual encoding in the Fresnel domain. Similar to the double random phase encoding (DRPE), this encryption scheme also employs a pair of phase-only functions (POFs) as encryption keys. But the two POFs are generated by the use of the MGSA rather than a random function generator. In the encryption process, only one color component is needed to be encrypted when these POFs are mutually served as the second encryption keys. As a result, a more compact and simple color encryption system based on one-time-pad, enabling only one gray cipheretext to be recorded and transmitted when holographic recording is used, is obtained. Moreover, the optical setup is lensless, thus easy to be implemented and the system parameters and wavelength can be served as additional keys to further enhance the security of the system. The feasibility and effectiveness of the proposed method are demonstrated by numerical results.
Bellemain, V
2012-08-01
Coordination between Veterinary Services and other relevant authorities is a key component of good public governance, especially for effective action and optimal management of available resources. The importance of good coordination is reflected in the World Organisation for Animal Health'Tool forthe Evaluation of Performance of Veterinary Services', which includes a critical competency on coordination. Many partners from technical, administrative and legal fields are involved. The degree of formalisation of coordination tends to depend on a country's level of organisation and development. Contingency plans against avian influenza led to breakthroughs in many countries in the mid-2000s. While interpersonal relationships remain vital, not everything should hinge on them. Organisation and management are critical to operational efficiency. The distribution of responsibilities needs to be defined clearly, avoiding duplication and areas of conflict. Lead authorities should be designated according to subject (Veterinary Services in animal health areas) and endowed with the necessary legitimacy. Lead authorities will be responsible for coordinating the drafting and updating of the relevant documents: agreements between authorities, contingency plans, standard operating procedures, etc.
Image encryption based on synchronization of fractional chaotic systems
NASA Astrophysics Data System (ADS)
Xu, Yong; Wang, Hua; Li, Yongge; Pei, Bin
2014-10-01
This paper deals with a synchronization scheme for two fractional chaotic systems which is applied in image encryption. Based on Pecora and Carroll (PC) synchronization, fractional-order Lorenz-like system forms a master-slave configuration, and the sufficient conditions are derived to realize synchronization between these two systems via the Laplace transformation theory. An image encryption algorithm is introduced where the original image is encoded by a nonlinear function of a fractional chaotic state. Simulation results show that the original image is well masked in the cipher texts and recovered successfully through chaotic signals. Further, the cryptanalysis is conducted in detail through histogram, information entropy, key space and sensitivity to verify the high security.
Binary-tree encryption strategy for optical multiple-image encryption.
Yi, Jiawang; Tan, Guanzheng
2016-07-10
In traditional optical multiple-image encryption schemes, different images typically have almost the same encryption or decryption process. Provided that an attacker manages to correctly decrypt some image, the conventional attacks upon other images are much easier to be made. In this paper, a binary-tree encryption strategy for multiple images is proposed to resist the attacks in this case. The encryption schemes produced by this strategy can not only increase the security of multiple-image encryption, but also realize an authority management with high security among the users sharing a cipher image. For a simulation test, we devise a basic binary-tree encryption scheme, whose encryption nodes are based on an asymmetric double random phase encoding in the gyrator domain. The favorable simulation results about the tested scheme can testify to the feasibility of the strategy.
NASA Astrophysics Data System (ADS)
Liu, Xingbin; Mei, Wenbo; Du, Huiqian
2016-05-01
In this paper, a novel approach based on compressive sensing and chaos is proposed for simultaneously compressing, fusing and encrypting multi-modal images. The sparsely represented source images are firstly measured with the key-controlled pseudo-random measurement matrix constructed using logistic map, which reduces the data to be processed and realizes the initial encryption. Then the obtained measurements are fused by the proposed adaptive weighted fusion rule. The fused measurement is further encrypted into the ciphertext through an iterative procedure including improved random pixel exchanging technique and fractional Fourier transform. The fused image can be reconstructed by decrypting the ciphertext and using a recovery algorithm. The proposed algorithm not only reduces data volume but also simplifies keys, which improves the efficiency of transmitting data and distributing keys. Numerical results demonstrate the feasibility and security of the proposed scheme.
Quantum image encryption based on generalized affine transform and logistic map
NASA Astrophysics Data System (ADS)
Liang, Hao-Ran; Tao, Xiang-Yang; Zhou, Nan-Run
2016-07-01
Quantum circuits of the generalized affine transform are devised based on the novel enhanced quantum representation of digital images. A novel quantum image encryption algorithm combining the generalized affine transform with logistic map is suggested. The gray-level information of the quantum image is encrypted by the XOR operation with a key generator controlled by the logistic map, while the position information of the quantum image is encoded by the generalized affine transform. The encryption keys include the independent control parameters used in the generalized affine transform and the logistic map. Thus, the key space is large enough to frustrate the possible brute-force attack. Numerical simulations and analyses indicate that the proposed algorithm is realizable, robust and has a better performance than its classical counterpart in terms of computational complexity.
Rajput, Sudheesh K; Nishchal, Naveen K
2014-01-20
We propose a novel nonlinear image-encryption scheme based on a Gerchberg-Saxton (G-S) phase-retrieval algorithm in the Fresnel transform domain. The decryption process can be performed using conventional double random phase encoding (DRPE) architecture. The encryption is realized by applying G-S phase-retrieval algorithm twice, which generates two asymmetric keys from intermediate phases. The asymmetric keys are generated in such a way that decryption is possible optically with a conventional DRPE method. Due to the asymmetric nature of the keys, the proposed encryption process is nonlinear and offers enhanced security. The cryptanalysis has been carried out, which proves the robustness of proposed scheme against known-plaintext, chosen-plaintext, and special attacks. A simple optical setup for decryption has also been suggested. Results of computer simulation support the idea of the proposed cryptosystem.
15 CFR Supplement No. 6 to Part 742 - Guidelines for Submitting Review Requests for Encryption Items
Code of Federal Regulations, 2010 CFR
2010-01-01
... asymmetric encryption algorithms and key lengths and how the algorithms are used, including relevant... cipher block chaining mode). (2) State the key management algorithms, including modulus sizes, that are supported. (3) For products with proprietary algorithms, include a textual description and the source...
NASA Astrophysics Data System (ADS)
Singh, Hukum
2016-12-01
A cryptosystem for securing image encryption is considered by using double random phase encoding in Fresnel wavelet transform (FWT) domain. Random phase masks (RPMs) and structured phase masks (SPMs) based on devil's vortex toroidal lens (DVTL) are used in spatial as well as in Fourier planes. The images to be encrypted are first Fresnel transformed and then single-level discrete wavelet transform (DWT) is apply to decompose LL,HL, LH and HH matrices. The resulting matrices from the DWT are multiplied by additional RPMs and the resultants are subjected to inverse DWT for the encrypted images. The scheme is more secure because of many parameters used in the construction of SPM. The original images are recovered by using the correct parameters of FWT and SPM. Phase mask SPM based on DVTL increases security that enlarges the key space for encryption and decryption. The proposed encryption scheme is a lens-less optical system and its digital implementation has been performed using MATLAB 7.6.0 (R2008a). The computed value of mean-squared-error between the retrieved and the input images shows the efficacy of scheme. The sensitivity to encryption parameters, robustness against occlusion, entropy and multiplicative Gaussian noise attacks have been analysed.
Multiple-image encryption based on compressive holography using a multiple-beam interferometer
NASA Astrophysics Data System (ADS)
Wan, Yuhong; Wu, Fan; Yang, Jinghuan; Man, Tianlong
2015-05-01
Multiple-image encryption techniques not only improve the encryption capacity but also facilitate the transmission and storage of the ciphertext. We present a new method of multiple-image encryption based on compressive holography with enhanced data security using a multiple-beam interferometer. By modifying the Mach-Zehnder interferometer, the interference of multiple object beams and unique reference beam is implemented for encrypting multiple images simultaneously into one hologram. The original images modulated with the random phase masks are put in different positions with different distance away from the CCD camera. Each image plays the role of secret key for other images to realize the mutual encryption. Four-step phase shifting technique is combined with the holographic recording. The holographic recording is treated as a compressive sensing process, thus the decryption process is inverted as a minimization problem and the two-step iterative shrinkage/thresholding algorithm (TwIST) is employed to solve this optimization problem. The simulated results about multiple binary and grayscale images encryption are demonstrated to verify the validity and robustness of our proposed method.
Compressive optical image encryption with two-step-only quadrature phase-shifting digital holography
NASA Astrophysics Data System (ADS)
Li, Jun; Li, Hongbing; Li, Jiaosheng; Pan, Yangyang; Li, Rong
2015-06-01
An image encryption method which combines two-step-only quadrature phase-shifting digital holography with compressive sensing (CS) has been proposed in the fully optical domain. An object image is firstly encrypted to two on-axis quadrature-phase holograms using the two random phase masks in the Mach-Zehnder interferometer. Then, the two encrypted images are highly compressed to a one-dimensional signal using the single-pixel compressive holographic imaging in the optical domain. At the receiving terminal, the two compressive encrypted holograms are exactly reconstructed from much less than the Nyquist sampling number of observations by solving an optimization problem, and the original image can be decrypted with only two reconstructed holograms and the correct keys. This method largely decreases holograms data volume for the current optical image encryption system, and it is also suitable for some special optical imaging cases such as different wavelengths imaging and weak light imaging. Numerical simulation is performed to demonstrate the feasibility and validity of this novel image encryption method.
NASA Astrophysics Data System (ADS)
Vilardy, Juan M.; Torres, Yezid; Millán, María S.; Pérez-Cabré, Elisabet
2014-12-01
We propose a generalization of the encryption system based on double random phase encoding (DRPE) and a joint transform correlator (JTC), from the Fourier domain to the fractional Fourier domain (FrFD) by using the fractional Fourier operators, such as the fractional Fourier transform (FrFT), fractional traslation, fractional convolution and fractional correlation. Image encryption systems based on a JTC architecture in the FrFD usually produce low quality decrypted images. In this work, we present two approaches to improve the quality of the decrypted images, which are based on nonlinear processing applied to the encrypted function (that contains the joint fractional power spectrum, JFPS) and the nonzero-order JTC in the FrFD. When the two approaches are combined, the quality of the decrypted image is higher. In addition to the advantages introduced by the implementation of the DRPE using a JTC, we demonstrate that the proposed encryption system in the FrFD preserves the shift-invariance property of the JTC-based encryption system in the Fourier domain, with respect to the lateral displacement of both the key random mask in the decryption process and the retrieval of the primary image. The feasibility of this encryption system is verified and analyzed by computer simulations.
Manticore and CS mode : parallelizable encryption with joint cipher-state authentication.
Torgerson, Mark Dolan; Draelos, Timothy John; Schroeppel, Richard Crabtree; Miller, Russell D.; Beaver, Cheryl Lynn; Anderson, William Erik
2004-10-01
We describe a new mode of encryption with inexpensive authentication, which uses information from the internal state of the cipher to provide the authentication. Our algorithms have a number of benefits: (1) the encryption has properties similar to CBC mode, yet the encipherment and authentication can be parallelized and/or pipelined, (2) the authentication overhead is minimal, and (3) the authentication process remains resistant against some IV reuse. We offer a Manticore class of authenticated encryption algorithms based on cryptographic hash functions, which support variable block sizes up to twice the hash output length and variable key lengths. A proof of security is presented for the MTC4 and Pepper algorithms. We then generalize the construction to create the Cipher-State (CS) mode of encryption that uses the internal state of any round-based block cipher as an authenticator. We provide hardware and software performance estimates for all of our constructions and give a concrete example of the CS mode of encryption that uses AES as the encryption primitive and adds a small speed overhead (10-15%) compared to AES alone.
15 CFR 742.15 - Encryption items.
Code of Federal Regulations, 2012 CFR
2012-01-01
... encryption software are distinguished from controls on other software regulated under the EAR. (a) Licensing... items (“EI”) classified under 5A002.a.1, .a.2, .a.5, .a.6, .a.9, and .b; 5D002.a, .c.1 or .d for... items and terms. Most encryption items may be exported under the provisions of License Exception ENC...
15 CFR 742.15 - Encryption items.
Code of Federal Regulations, 2013 CFR
2013-01-01
... encryption software are distinguished from controls on other software regulated under the EAR. (a) Licensing... items (“EI”) classified under 5A002.a.1, .a.2, .a.5, .a.6, .a.9, and .b; 5D002.a, .c.1 or .d for... items and terms. Most encryption items may be exported under the provisions of License Exception ENC...
15 CFR 742.15 - Encryption items.
Code of Federal Regulations, 2014 CFR
2014-01-01
... encryption software are distinguished from controls on other software regulated under the EAR. (a) Licensing... items (“EI”) classified under 5A002.a.1, .a.2, .a.5, .a.6, .a.9, and .b; 5D002.a, .c.1 or .d for... items and terms. Most encryption items may be exported under the provisions of License Exception ENC...
Space-based optical image encryption.
Chen, Wen; Chen, Xudong
2010-12-20
In this paper, we propose a new method based on a three-dimensional (3D) space-based strategy for the optical image encryption. The two-dimensional (2D) processing of a plaintext in the conventional optical encryption methods is extended to a 3D space-based processing. Each pixel of the plaintext is considered as one particle in the proposed space-based optical image encryption, and the diffraction of all particles forms an object wave in the phase-shifting digital holography. The effectiveness and advantages of the proposed method are demonstrated by numerical results. The proposed method can provide a new optical encryption strategy instead of the conventional 2D processing, and may open up a new research perspective for the optical image encryption.
A time-variant approach for encrypted digital communications
NASA Astrophysics Data System (ADS)
Ng, Wai-Hung
Two new approaches, a time-variant key and a random transmission rate, are introduced to strengthen the security of encrypted digital communications in which a 'black-box' type of crypto-device is employed. These approaches not only further upgrade present cryto-methodology, but may also secure the system against the possibility of the crytographic key's falling into the hands of an unauthorized listener after initial communication has begun. Therefore, communication privacy could be maintained even under the most scrutinizing postrecorded ciphertext attack.
Quantum image encryption based on generalized Arnold transform and double random-phase encoding
NASA Astrophysics Data System (ADS)
Zhou, Nan Run; Hua, Tian Xiang; Gong, Li Hua; Pei, Dong Ju; Liao, Qing Hong
2015-04-01
A quantum realization of the generalized Arnold transform is designed. A novel quantum image encryption algorithm based on generalized Arnold transform and double random-phase encoding is proposed. The pixels are scrambled by the generalized Arnold transform, and the gray-level information of images is encoded by the double random-phase operations. The keys of the encryption algorithm include the independent parameters of coefficients matrix, iterative times and classical binary sequences, and thus, the key space is extremely large. Numerical simulations and theoretical analyses demonstrate that the proposed algorithm with good feasibility and effectiveness has lower computational complexity than its classical counterpart.
NASA Astrophysics Data System (ADS)
Bates, Alison Waterbury
been proposed. The essay examines how the public considers the societal tradeoffs that are made to develop small-scale, in-view demonstration wind projects instead of larger facilities farther offshore. Results indicate that a strong majority of the public supports near-shore demonstration wind projects in both states. Primary reasons for support include benefits to wildlife, cost of electricity, and job creation, while the primary reasons for opposition include wildlife impacts, aesthetics, tourism, and user conflicts. These factors differ between coastal Delaware and greater Atlantic City and highlight the importance of local, community engagement in the early stages of development. The second essay examines the interaction of a new proposed use of the ocean---offshore wind---and a key existing ocean user group---commercial fishers. A key component of offshore wind planning includes consideration of existing uses of the marine environment in order to optimally site wind projects while minimizing conflicts. Commercial fisheries comprise an important stakeholder group, and may be one of the most impacted stakeholders from offshore renewable energy development. Concern of the fishing industry stems from possible interference with productive fishing grounds and access within wind developments resulting in costs from increased effort or reduction in catch. Success of offshore wind development may in part depend on the acceptance of commercial fishers, who are concerned about loss of access to fishing grounds. Using a quantitative, marine spatial planning approach in the siting of offshore wind projects with respect to commercial fishing in the mid-Atlantic, U.S., this essay develops a spatially explicit representation of potential conflicts and compatibilities between these two industries in the mid-Atlantic region of the United States. Areas that are highly valuable to the wind industry are determined through a spatial suitability model using variable cost per unit
2015-05-01
MAIS) acquisition effort. “PKI” refers to the framework and services that provide for the generation, production, distribution, control, revocation ...Infrastructure (PKI) refers to the framework and services that provide for the generation, production, distribution, control, revocation , recovery, and...production, distribution, control, revocation , recovery, storage, destruction, and accounting of public and private key certificates. DoD PKI system
Limitations on information-theoretically-secure quantum homomorphic encryption
NASA Astrophysics Data System (ADS)
Yu, Li; Pérez-Delgado, Carlos A.; Fitzsimons, Joseph F.
2014-11-01
Homomorphic encryption is a form of encryption which allows computation to be carried out on the encrypted data without the need for decryption. The success of quantum approaches to related tasks in a delegated computation setting has raised the question of whether quantum mechanics may be used to achieve information-theoretically-secure fully homomorphic encryption. Here we show, via an information localization argument, that deterministic fully homomorphic encryption necessarily incurs exponential overhead if perfect security is required.
Multiple image encryption by phase retrieval
NASA Astrophysics Data System (ADS)
Di, Hong; Kang, Yanmei; Liu, Yueqin; Zhang, Xin
2016-07-01
Multiple image encryption (MIE) was proposed to increase the efficiency of encrypting images by processing several images simultaneously. Because of the advantage of optical technology in processing twodimensional images at high throughput, MIE has been significantly improved by use of methods originating from optics. Phase retrieval was the process of algorithmically finding solutions to the phase loss problem due to light detectors only capturing the intensity. It was to retrieve phase information for the determination of a structure from diffraction data. Error-reduction algorithm is a typical phase retrieval method. Here, we employ it to illustrate that methods in phase retrieval are able to encrypt multiple images and compress them into encrypted data simultaneously. Moreover, the decryption is also designed to handle multiple images at the same time. The whole process including both the encryption and decryption is proposed to improve MIE with respect to the compression and efficiency. The feasibility and encryption of the MIE scheme is demonstrated with encryption experiments under Gaussian white noise and unauthorized access.
Kotwicki, Raymond J; Compton, Michael T
2010-08-01
The Emory University Fellowship in Community Psychiatry/Public Health is a unique training opportunity whose mission is to train future leaders in the arena of community psychiatry. To complement the recent description of the Public Psychiatry Fellowship of New York State Psychiatric Institute at Columbia University Medical Center, this report describes the key features of Emory's fellowship-its academic curriculum, practicum experiences, site visits and other opportunities for collaboration, and ongoing mentoring and career development. Congruencies between these four key features and the seven core elements of Columbia's fellowship are highlighted, as are several important differences. Such descriptions of innovative training programs in community and public psychiatry are essential in promoting excellence in education, which will translate into vital enhancements in programs, policy, and community-based approaches to mental health services.
A fast image encryption algorithm based on only blocks in cipher text
NASA Astrophysics Data System (ADS)
Wang, Xing-Yuan; Wang, Qian
2014-03-01
In this paper, a fast image encryption algorithm is proposed, in which the shuffling and diffusion is performed simultaneously. The cipher-text image is divided into blocks and each block has k ×k pixels, while the pixels of the plain-text are scanned one by one. Four logistic maps are used to generate the encryption key stream and the new place in the cipher image of plain image pixels, including the row and column of the block which the pixel belongs to and the place where the pixel would be placed in the block. After encrypting each pixel, the initial conditions of logistic maps would be changed according to the encrypted pixel's value; after encrypting each row of plain image, the initial condition would also be changed by the skew tent map. At last, it is illustrated that this algorithm has a faster speed, big key space, and better properties in withstanding differential attacks, statistical analysis, known plaintext, and chosen plaintext attacks.
A Signcryption based Light Weight Key Exchange Protocol
NASA Astrophysics Data System (ADS)
Feng, Yong; Wei, Qian; Zhang, Xing
Traditional cryptography based authenticated Diffie-Hellman key exchange protocols expose the problems of efficiency and privacy since signature-then-encryption is heavy to wireless communication special for flexible dynamic deployment, i.e., wireless mesh networks, wireless sensor networks, mobile ad hoc networks, etc., in computational cost and communicational overhead and traditional digital signature allows anyone to verify its validity using the corresponding public key. In this paper, we propose a signcryption based light weight key exchange protocol named SLWKE which can provide resistance to traditional attacks, i.e., eavesdropping, deducing, replaying, interleaving, forging and repudiating, and unknown key-share attack and save computational cost by three modular calculations, i.e., one modular inversion, one modular addition and one modular multiplicative, included in a signature s and communicational overhead by secure length of IqI in comparison to signcryption based direct key exchange using a time-stamp protocol termed Dkeuts.
Video Encryption and Decryption on Quantum Computers
NASA Astrophysics Data System (ADS)
Yan, Fei; Iliyasu, Abdullah M.; Venegas-Andraca, Salvador E.; Yang, Huamin
2015-08-01
A method for video encryption and decryption on quantum computers is proposed based on color information transformations on each frame encoding the content of the encoding the content of the video. The proposed method provides a flexible operation to encrypt quantum video by means of the quantum measurement in order to enhance the security of the video. To validate the proposed approach, a tetris tile-matching puzzle game video is utilized in the experimental simulations. The results obtained suggest that the proposed method enhances the security and speed of quantum video encryption and decryption, both properties required for secure transmission and sharing of video content in quantum communication.
NASA Astrophysics Data System (ADS)
Oppenheim, Jonathan; Horodecki, Michał
2005-10-01
Quantum information is a valuable resource which can be encrypted in order to protect it. We consider the size of the one-time pad that is needed to protect quantum information in a number of cases. The situation is dramatically different from the classical case: we prove that one can recycle the one-time pad without compromising security. The protocol for recycling relies on detecting whether eavesdropping has occurred, and further relies on the fact that information contained in the encrypted quantum state cannot be fully accessed. We prove the security of recycling rates when authentication of quantum states is accepted, and when it is rejected. We note that recycling schemes respect a general law of cryptography which we introduce relating the size of private keys, sent qubits, and encrypted messages. We discuss applications for encryption of quantum information in light of the resources needed for teleportation. Potential uses include the protection of resources such as entanglement and the memory of quantum computers. We also introduce another application: encrypted secret sharing and find that one can even reuse the private key that is used to encrypt a classical message. In a number of cases, one finds that the amount of private key needed for authentication or protection is smaller than in the general case.
Oppenheim, Jonathan; Horodecki, Michal
2005-10-15
Quantum information is a valuable resource which can be encrypted in order to protect it. We consider the size of the one-time pad that is needed to protect quantum information in a number of cases. The situation is dramatically different from the classical case: we prove that one can recycle the one-time pad without compromising security. The protocol for recycling relies on detecting whether eavesdropping has occurred, and further relies on the fact that information contained in the encrypted quantum state cannot be fully accessed. We prove the security of recycling rates when authentication of quantum states is accepted, and when it is rejected. We note that recycling schemes respect a general law of cryptography which we introduce relating the size of private keys, sent qubits, and encrypted messages. We discuss applications for encryption of quantum information in light of the resources needed for teleportation. Potential uses include the protection of resources such as entanglement and the memory of quantum computers. We also introduce another application: encrypted secret sharing and find that one can even reuse the private key that is used to encrypt a classical message. In a number of cases, one finds that the amount of private key needed for authentication or protection is smaller than in the general case.
Wang, Qu; Guo, Qing; Zhou, Jinyun
2013-12-20
We propose a multiple-image encryption scheme, based on polarized light encoding and the interference principle of phase-only masks (POMs), in the Fresnel-transform (FrT) domain. In this scheme, each secret image is converted into an intensity image by polarized light encoding, where a random key image and a pixilated polarizer with random angles are employed as keys. The intensity encrypted images produced by different secret images are convolved together and then inverse Fresnel-transformed. Phase and amplitude truncations are used to generate the asymmetric decryption keys. The phase-truncated inverse FrT spectrum is sent into an interference-based encryption (IBE) system to analytically obtain two POMs. To reduce the transmission and storage load on the keys, the chaotic mapping method is employed to generate random distributions of keys for encryption and decryption. One can recover all secret images successfully only if the corresponding decryption keys, the mechanism of FrTs, and correct chaotic conditions are known. The inherent silhouette problem can be thoroughly resolved by polarized light encoding in this proposal, without using any time-consuming iterative methods. The entire encryption and decryption process can be realized digitally, or in combination with optical means. Numerical simulation results are presented to verify the effectiveness and performance of the proposed scheme.
A sensitive data extraction algorithm based on the content associated encryption technology for ICS
NASA Astrophysics Data System (ADS)
Wang, Wei; Hao, Huang; Xie, Changsheng
With the development of HD video, the protection of copyright becomes more complicated. More advanced copyright protection technology is needed. Traditional digital copyright protection technology generally uses direct or selective encryption algorithm and the key does not associate with the video content [1]. Once the encryption method is cracked or the key is stolen, the copyright of the video will be violated. To address this issue, this paper proposes a Sensitive Data Extraction Algorithm (SDEA) based on the content associated encryption technology which applies to the Internet Certification Service (ICS). The principle of content associated encryption is to extract some data from the video and use this extracted data as the key to encrypt the rest data. The extracted part from video is called sensitive data, and the rest part is called the main data. After extraction, the main data will not be played or poorly played. The encrypted sensitive data reach the terminal device through the safety certificated network and the main data are through ICS disc. The terminal equipments are responsible for synthesizing and playing these two parts of data. Consequently, even if the main data on disc is illegally obtained, the video cannot be played normally due to the lack of necessary sensitive data. It is proved by experiments that ICS using SDEA can destruct the video effectively with 0.25% extraction rates and the destructed video cannot be played well. It can also guarantee the consistency of the destructive effect on different videos with different contents. The sensitive data can be transported smoothly under the home Internet bandwidth.
WEDDS: The WITS Encrypted Data Delivery System
NASA Technical Reports Server (NTRS)
Norris, J.; Backes, P.
1999-01-01
WEDDS, the WITS Encrypted Data Delivery System, is a framework for supporting distributed mission operations by automatically transferring sensitive mission data in a secure and efficient manner to and from remote mission participants over the internet.
Code of Federal Regulations, 2014 CFR
2014-10-01
... (AES) specified in ANSI/TIA-102.AAAD-A: Project 25 Digital Land Mobile Radio-Block Encryption Protocol... Standards Institute, 25 West 43rd Street, Fourth Floor, New York, NY 10036 (or via the Internet at...
Key management schemes using routing information frames in secure wireless sensor networks
NASA Astrophysics Data System (ADS)
Kamaev, V. A.; Finogeev, A. G.; Finogeev, A. A.; Parygin, D. S.
2017-01-01
The article considers the problems and objectives of key management for data encryption in wireless sensor networks (WSN) of SCADA systems. The structure of the key information in the ZigBee network and methods of keys obtaining are discussed. The use of a hybrid key management schemes is most suitable for WSN. The session symmetric key is used to encrypt the sensor data, asymmetric keys are used to encrypt the session key transmitted from the routing information. Three algorithms of hybrid key management using routing information frames determined by routing methods and the WSN topology are presented.
Securing information using optically generated biometric keys
NASA Astrophysics Data System (ADS)
Verma, Gaurav; Sinha, Aloka
2016-11-01
In this paper, we present a new technique to obtain biometric keys by using the fingerprint of a person for an optical image encryption system. The key generation scheme uses the fingerprint biometric information in terms of the amplitude mask (AM) and the phase mask (PM) of the reconstructed fingerprint image that is implemented using the digital holographic technique. Statistical tests have been conducted to check the randomness of the fingerprint PM key that enables its usage as an image encryption key. To explore the utility of the generated biometric keys, an optical image encryption system has been further demonstrated based on the phase retrieval algorithm and the double random phase encoding scheme in which keys for the encryption are used as the AM and the PM key. The advantage associated with the proposed scheme is that the biometric keys’ retrieval requires the simultaneous presence of the fingerprint hologram and the correct knowledge of the reconstruction parameters at the decryption stage, which not only verifies the authenticity of the person but also protects the valuable fingerprint biometric features of the keys. Numerical results are carried out to prove the feasibility and the effectiveness of the proposed encryption system.
Symmetric encryption algorithms using chaotic and non-chaotic generators: A review.
Radwan, Ahmed G; AbdElHaleem, Sherif H; Abd-El-Hafiz, Salwa K
2016-03-01
This paper summarizes the symmetric image encryption results of 27 different algorithms, which include substitution-only, permutation-only or both phases. The cores of these algorithms are based on several discrete chaotic maps (Arnold's cat map and a combination of three generalized maps), one continuous chaotic system (Lorenz) and two non-chaotic generators (fractals and chess-based algorithms). Each algorithm has been analyzed by the correlation coefficients between pixels (horizontal, vertical and diagonal), differential attack measures, Mean Square Error (MSE), entropy, sensitivity analyses and the 15 standard tests of the National Institute of Standards and Technology (NIST) SP-800-22 statistical suite. The analyzed algorithms include a set of new image encryption algorithms based on non-chaotic generators, either using substitution only (using fractals) and permutation only (chess-based) or both. Moreover, two different permutation scenarios are presented where the permutation-phase has or does not have a relationship with the input image through an ON/OFF switch. Different encryption-key lengths and complexities are provided from short to long key to persist brute-force attacks. In addition, sensitivities of those different techniques to a one bit change in the input parameters of the substitution key as well as the permutation key are assessed. Finally, a comparative discussion of this work versus many recent research with respect to the used generators, type of encryption, and analyses is presented to highlight the strengths and added contribution of this paper.
Comment on ‘A technique for image encryption using digital signature’
NASA Astrophysics Data System (ADS)
Hernández Encinas, L.; Peinado Domínguez, A.
2006-12-01
The security of a recently proposed technique for encryption images by Sinha and Singh [A. Sinha, K. Singh, Opt. Commun. 218 (2003) 229], based on the use of digital signatures and error correcting codes, is analyzed. The proposed cryptosystem is shown to have some weakness. In fact, the secret key and the original image can be recovered efficiently by a brute force attack.
15 CFR Supplement No. 8 to Part 742 - Self-Classification Report for Encryption Items
Code of Federal Regulations, 2014 CFR
2014-01-01
...) Key storage (xix) Link encryption (xx) Local area networking (LAN) (xxi) Metropolitan area networking (MAN) (xxii) Modem (xxiii) Network convergence or infrastructure n.e.s. (xxiv) Network forensics (xxv...) Voice over Internet protocol (VoIP) (xlii) Wide area networking (WAN) (xliii) Wireless local...
15 CFR Supplement No. 8 to Part 742 - Self-Classification Report for Encryption Items
Code of Federal Regulations, 2013 CFR
2013-01-01
...) Key storage (xix) Link encryption (xx) Local area networking (LAN) (xxi) Metropolitan area networking...) Network intelligence (xxvi) Network or systems management (OAM/OAM&P) (xxvii) Network security monitoring...) Voice over Internet protocol (VoIP) (xlii) Wide area networking (WAN) (xliii) Wireless local...
15 CFR Supplement No. 8 to Part 742 - Self-Classification Report for Encryption Items
Code of Federal Regulations, 2011 CFR
2011-01-01
...) Key storage (xix) Link encryption (xx) Local area networking (LAN) (xxi) Metropolitan area networking...) Network intelligence (xxvi) Network or systems management (OAM/OAM&P) (xxvii) Network security monitoring...) Voice over Internet protocol (VoIP) (xlii) Wide area networking (WAN) (xliii) Wireless local...
15 CFR Supplement No. 8 to Part 742 - Self-Classification Report for Encryption Items
Code of Federal Regulations, 2012 CFR
2012-01-01
...) Key storage (xix) Link encryption (xx) Local area networking (LAN) (xxi) Metropolitan area networking...) Network intelligence (xxvi) Network or systems management (OAM/OAM&P) (xxvii) Network security monitoring...) Voice over Internet protocol (VoIP) (xlii) Wide area networking (WAN) (xliii) Wireless local...
Symmetric encryption algorithms using chaotic and non-chaotic generators: A review
Radwan, Ahmed G.; AbdElHaleem, Sherif H.; Abd-El-Hafiz, Salwa K.
2015-01-01
This paper summarizes the symmetric image encryption results of 27 different algorithms, which include substitution-only, permutation-only or both phases. The cores of these algorithms are based on several discrete chaotic maps (Arnold’s cat map and a combination of three generalized maps), one continuous chaotic system (Lorenz) and two non-chaotic generators (fractals and chess-based algorithms). Each algorithm has been analyzed by the correlation coefficients between pixels (horizontal, vertical and diagonal), differential attack measures, Mean Square Error (MSE), entropy, sensitivity analyses and the 15 standard tests of the National Institute of Standards and Technology (NIST) SP-800-22 statistical suite. The analyzed algorithms include a set of new image encryption algorithms based on non-chaotic generators, either using substitution only (using fractals) and permutation only (chess-based) or both. Moreover, two different permutation scenarios are presented where the permutation-phase has or does not have a relationship with the input image through an ON/OFF switch. Different encryption-key lengths and complexities are provided from short to long key to persist brute-force attacks. In addition, sensitivities of those different techniques to a one bit change in the input parameters of the substitution key as well as the permutation key are assessed. Finally, a comparative discussion of this work versus many recent research with respect to the used generators, type of encryption, and analyses is presented to highlight the strengths and added contribution of this paper. PMID:26966561
Multiple-image encryption based on triple interferences for flexibly decrypting high-quality images.
Li, Wei-Na; Phan, Anh-Hoang; Piao, Mei-Lan; Kim, Nam
2015-04-10
We propose a multiple-image encryption (MIE) scheme based on triple interferences for flexibly decrypting high-quality images. Each image is discretionarily deciphered without decrypting a series of other images earlier. Since it does not involve any cascaded encryption orders, the image can be decrypted flexibly by using the novel method. Computer simulation demonstrated that the proposed method's running time is less than approximately 1/4 that of the previous similar MIE method. Moreover, the decrypted image is perfectly correlated with the original image, and due to many phase functions serving as decryption keys, this method is more secure and robust.
NASA Astrophysics Data System (ADS)
Li, Xin-Xin; Zhao, Dao-Mu
2008-07-01
We present a new method for image encryption on the basis of simplified fractional Hartley transform (SFRHT). SFRHT is a real transform as Hartley transform (HT) and furthermore, superior to HT in virtue of the advantage that it can also append fractional orders as additional keys for the purpose of improving the system security to some extent. With this method, one can encrypt an image with an intensity-only medium such as a photographic film or a CCD camera by spatially incoherent or coherent illumination. The optical realization is then proposed and computer simulations are also performed to verify the feasibility of this method.
A Novel Color Image Encryption Algorithm Based on Quantum Chaos Sequence
NASA Astrophysics Data System (ADS)
Liu, Hui; Jin, Cong
2017-03-01
In this paper, a novel algorithm of image encryption based on quantum chaotic is proposed. The keystreams are generated by the two-dimensional logistic map as initial conditions and parameters. And then general Arnold scrambling algorithm with keys is exploited to permute the pixels of color components. In diffusion process, a novel encryption algorithm, folding algorithm, is proposed to modify the value of diffused pixels. In order to get the high randomness and complexity, the two-dimensional logistic map and quantum chaotic map are coupled with nearest-neighboring coupled-map lattices. Theoretical analyses and computer simulations confirm that the proposed algorithm has high level of security.
Fractional Fourier transform-based optical encryption with treble random phase-encoding
NASA Astrophysics Data System (ADS)
Xin, Yi; Tao, Ran; Wang, Yue
2008-03-01
We propose a new architecture of optical encryption technique using the fractional Fourier transform with three statistically independent random phase masks. Compared with the existing double-phase encoding method in the fractional Fourier-domain, the proposed extra phase mask in the last fractional Fourier domain makes the architecture symmetrical, and additive processing to the encrypted image can be turned into complex stationary white noise after decryption, and enlarge the key space without any degradation of its robustness to blind decryption. This property can be utilized to improve the quality of the recover image. Simulation results have verified the validity.
Encrypting 2D/3D image using improved lensless integral imaging in Fresnel domain
NASA Astrophysics Data System (ADS)
Li, Xiao-Wei; Wang, Qiong-Hua; Kim, Seok-Tae; Lee, In-Kwon
2016-12-01
We propose a new image encryption technique, for the first time to our knowledge, combined Fresnel transform with the improved lensless integral imaging technique. In this work, before image encryption, the input image is first recorded into an elemental image array (EIA) by using the improved lensless integral imaging technique. The recorded EIA is encrypted into random noise by use of two phase masks located in the Fresnel domain. The positions of phase masks and operation wavelength, as well as the integral imaging system parameters are used as encryption keys that can ensure security. Compared with previous works, the main novelty of this proposed method resides in the fact that the elemental images possess distributed memory characteristic, which greatly improved the robustness of the image encryption algorithm. Meanwhile, the proposed pixel averaging algorithm can effectively address the overlapping problem existing in the computational integral imaging reconstruction process. Numerical simulations are presented to demonstrate the feasibility and effectiveness of the proposed method. Results also indicate the high robustness against data loss attacks.
Scalable end-to-end encryption technology for supra-gigabit/second networking
Pierson, L.G.; Tarman, T.D.; Witzke, E.L.
1997-05-01
End-to-end encryption can protect proprietary information as it passes through a complex inter-city computer network, even if the intermediate systems are untrusted. This technique involves encrypting the body of computer messages while leaving network addressing and control information unencrypted for processing by intermediate network nodes. Because high speed implementations of end-to-end encryption with easy key management for standard network protocols are unavailable, this technique is not widely used today. Specifically, no end-to-end encryptors exist to protect Asynchronous Transfer Mode (ATM) traffic, nor to protect Switched Multi-megabit Data Service (SMDS), which is the first ``Broadband Integrated Services Digital Network`` (BISDN) service now being used by long distance telephone companies. This encryption technology is required for the protection of data in transit between industrial sites and central Massively Parallel Supercomputing Centers over high bandwidth, variable bit rate (BISDN) services. This research effort investigated techniques to scale end-to-end encryption technology from today`s state of the art ({approximately} 0.001 Gb/s) to 2.4 Gb/s and higher. A cryptosystem design has been developed which scales for implementation beyond SONET OC-48 (2.4Gb/s) data rates. A prototype for use with OC-3 (0.155 Gb/s) ATM variable bit rate services was developed.
A novel chaos-based bit-level permutation scheme for digital image encryption
NASA Astrophysics Data System (ADS)
Fu, Chong; Lin, Bin-bin; Miao, Yu-sheng; Liu, Xiao; Chen, Jun-jie
2011-11-01
Confidentiality is an important issue when digital images are transmitted over public networks, and encryption is the most useful technique employed for this purpose. Image encryption is somehow different from text encryption due to some inherent features of image such as bulk data capacity and high correlation among pixels, which are generally difficult to handle by conventional algorithms. Recently, chaos-based encryption has suggested a new and efficient way to deal with the intractable problems of fast and highly secure image encryption. This paper proposes a novel chaos-based bit-level permutation scheme for secure and efficient image cipher. To overcome the drawbacks of conventional permutation-only type image cipher, the proposed scheme introduced a significant diffusion effect in permutation procedure through a two-stage bit-level shuffling algorithm. The two-stage permutation operations are realized by chaotic sequence sorting algorithm and Arnold Cat map, respectively. Results of various types of analysis are interesting and indicate that the security level of the new scheme is competitive with that of permutation-diffusion type image cipher, while the computational complexity is much lower. Therefore the new scheme is a good candidate for real-time secure image communication applications.
Translating research for evidence-based public health: key concepts and future directions.
Rychetnik, Lucie; Bauman, Adrian; Laws, Rachel; King, Lesley; Rissel, Chris; Nutbeam, Don; Colagiuri, Stephen; Caterson, Ian
2012-12-01
Applying research to guide evidence-based practice is an ongoing and significant challenge for public health. Developments in the emerging field of 'translation' have focused on different aspects of the problem, resulting in competing frameworks and terminology. In this paper the scope of 'translation' in public health is defined, and four related but conceptually different 'translation processes' that support evidence-based practice are outlined: (1) reviewing the transferability of evidence to new settings, (2) translation research, (3) knowledge translation, and (4) knowledge translation research. Finally, an integrated framework is presented to illustrate the relationship between these domains, and priority areas for further development and empirical research are identified.
A self-adaptive image encryption scheme with half-pixel interchange permutation operation
NASA Astrophysics Data System (ADS)
Ye, Ruisong; Liu, Li; Liao, Minyu; Li, Yafang; Liao, Zikang
2017-01-01
A plain-image dependent image encryption scheme with half-pixel-level swapping permutation strategy is proposed. In the new permutation operation, a pixel-swapping operation between four higher bit-planes and four lower bit-planes is employed to replace the traditional confusion operation, which not only improves the conventional permutation efficiency within the plain-image, but also changes all the pixel gray values. The control parameters of generalized Arnold map applied for the permutation operation are related to the plain-image content and consequently can resist chosen-plaintext and known-plaintext attacks effectively. To enhance the security of the proposed image encryption, one multimodal skew tent map is applied to generate pseudo-random gray value sequence for diffusion operation. Simulations have been carried out thoroughly to demonstrate that the proposed image encryption scheme is highly secure thanks to its large key space and efficient permutation-diffusion operations.
Fully phase image encryption using double random-structured phase masks in gyrator domain.
Singh, Hukum; Yadav, A K; Vashisth, Sunanda; Singh, Kehar
2014-10-01
We propose a method for fully phase image encryption based on double random-structured phase mask encoding in the gyrator transform (GT) domain. The security of the system is strengthened by parameters used in the construction of a structured phase mask (SPM) based on a devil's vortex Fresnel lens (DVFL). The input image is recovered using the correct parameters of the SPMs, transform orders of the GT, and conjugate of the random phase masks. The use of a DVFL-based SPM enhances security by increasing the key space for encryption, and also overcomes the problem of axis alignment associated with an optical setup. The proposed scheme can also be implemented optically. The computed values of mean squared error between the retrieved and the original image show the efficacy of the proposed scheme. We have also investigated the scheme's sensitivity to the encryption parameters, and robustness against occlusion and multiplicative Gaussian noise attacks.
Texture Analysis of Chaotic Coupled Map Lattices Based Image Encryption Algorithm
NASA Astrophysics Data System (ADS)
Khan, Majid; Shah, Tariq; Batool, Syeda Iram
2014-09-01
As of late, data security is key in different enclosures like web correspondence, media frameworks, therapeutic imaging, telemedicine and military correspondence. In any case, a large portion of them confronted with a few issues, for example, the absence of heartiness and security. In this letter, in the wake of exploring the fundamental purposes of the chaotic trigonometric maps and the coupled map lattices, we have presented the algorithm of chaos-based image encryption based on coupled map lattices. The proposed mechanism diminishes intermittent impact of the ergodic dynamical systems in the chaos-based image encryption. To assess the security of the encoded image of this scheme, the association of two nearby pixels and composition peculiarities were performed. This algorithm tries to minimize the problems arises in image encryption.
NASA Astrophysics Data System (ADS)
Chen, Linfei; Chang, Guojun; He, Bingyu; Mao, Haidan; Zhao, Daomu
2017-01-01
In this paper, an optical encryption system is proposed based on tricolor principle, Fresnel diffraction, and phase iterative algorithms. Different from the traditional encryption system, the encrypted image of this system is a color image and the plaintext of it is a gray image, which can achieve the combination of a color image and a gray image and the conversion of one image to another image. Phase masks can be generated by using the phase iterative algorithms in this paper. The six phase masks and the six diffracting distances are all essential keys in the process of decryption, which can greatly enhance the system security. Numerical simulations are shown to prove the possibility and safety of the method.
Interviewing Key Informants: Strategic Planning for a Global Public Health Management Program
ERIC Educational Resources Information Center
Kun, Karen E.; Kassim, Anisa; Howze, Elizabeth; MacDonald, Goldie
2013-01-01
The Centers for Disease Control and Prevention's Sustainable Management Development Program (SMDP) partners with low- and middle-resource countries to develop management capacity so that effective global public health programs can be implemented and better health outcomes can be achieved. The program's impact however, was variable. Hence, there…
ERIC Educational Resources Information Center
Kayaga, Sam
2007-01-01
The capacity of public service staff in developing countries is crucial for achieving the Millennium Development Goals. Literature from developed countries shows that, working with higher education institutions (HEIs), industries have improved their human resource capacity through continuing professional development. This paper reports on research…
Public-private relationships in biobanking: a still underestimated key component of open innovation.
Hofman, Paul; Bréchot, Christian; Zatloukal, Kurt; Dagher, Georges; Clément, Bruno
2014-01-01
Access to human bioresources is essential to the understanding of human diseases and to the discovery of new biomarkers aimed at improving the diagnosis, prognosis, and the predictive response of patients to treatments. The use of biospecimens is strictly controlled by ethical assessment, which complies with the laws of the country. These laws regulate the partnerships between the biobanks and industrial actors. However, private-public partnerships (PPP) can be limiting for several reasons, which can hamper the discovery of new biological tests and new active molecules targeted to human diseases. The bottlenecks and roadblocks in establishing these partnerships include: poor organization of the biobank in setting up PPP, evaluation of the cost of human samples, the absence of experience on the public side in setting up contracts with industry, and the fact that public and private partners may not share the same objectives. However, it is critical, in particular for academic biobanks, to establish strong PPP to accelerate translational research for the benefits of patients, and to allow the sustainability of the biobank. The purpose of this review is to discuss the main bottlenecks and roadblocks that can hamper the establishment of PPP based on solid and trusting relationships.
Su, Yonggang; Tang, Chen; Li, Biyuan; Chen, Xia; Xu, Wenjun; Cai, Yuanxue
2017-01-20
We propose an optical color image encryption system based on the single-lens Fourier transform, the Fresnel transform, and the chaotic random phase masks (CRPMs). The proposed encryption system contains only one optical lens, which makes it more efficient and concise to implement. The introduction of the Fresnel transform makes the first phase mask of the proposed system also act as the main secret key when the input image is a non-negative amplitude-only map. The two CRPMs generated by dual two-dimensional chaotic maps can provide more security to the proposed system. In the proposed system, the key management is more convenient and the transmission volume is reduced greatly. In addition, the secret keys can be updated conveniently in each encryption process to invalidate the chosen plaintext attack and the known plaintext attack. Numerical simulation results have demonstrated the feasibility and security of the proposed encryption system.
Implementation notes on bdes(1). [data encryption implementation
NASA Technical Reports Server (NTRS)
Bishop, Matt
1991-01-01
This note describes the implementation of bdes, the file encryption program being distributed in the 4.4 release of the Berkeley Software Distribution. It implements all modes of the Data Encryption Standard program.
An algorithm for encryption of secret images into meaningful images
NASA Astrophysics Data System (ADS)
Kanso, A.; Ghebleh, M.
2017-03-01
Image encryption algorithms typically transform a plain image into a noise-like cipher image, whose appearance is an indication of encrypted content. Bao and Zhou [Image encryption: Generating visually meaningful encrypted images, Information Sciences 324, 2015] propose encrypting the plain image into a visually meaningful cover image. This improves security by masking existence of encrypted content. Following their approach, we propose a lossless visually meaningful image encryption scheme which improves Bao and Zhou's algorithm by making the encrypted content, i.e. distortions to the cover image, more difficult to detect. Empirical results are presented to show high quality of the resulting images and high security of the proposed algorithm. Competence of the proposed scheme is further demonstrated by means of comparison with Bao and Zhou's scheme.
Why sustainable population growth is a key to climate change and public health equity.
Howat, Peter; Stoneham, Melissa
2011-12-01
Australia's population could reach 42 million by 2050. This rapid population growth, if unabated, will have significant social, public health and environmental implications. On the one hand, it is a major driver of climate change and environmental degradation; on the other it is likely to be a major contributor to growing social and health issues including a decline in quality of life for many residents. Disadvantaged and vulnerable groups will be most affected. The environmental, social and health-related issues include: pressure on the limited arable land in Australia; increased volumes of industrial and domestic waste; inadequate essential services; traffic congestion; lack of affordable housing; declining mental health; increased obesity problems; and inadequate aged care services. Many of these factors are related to the aggravation of climate change and health inequities. It is critical that the Australian Government develops a sustainable population plan with stabilisation of population growth as an option. The plan needs to ensure adequate hospitals and healthcare services, education facilities, road infrastructure, sustainable transport options, water quality and quantity, utilities and other amenities that are already severely overburdened in Australian cities. There is a need for a guarantee that affordable housing will be available and priority be given to training young people and Indigenous people for employment. This paper presents evidence to support the need for the stabilisation of population growth as one of the most significant measures to control climate change as well as to improve public health equity.
A chaos-based digital image encryption scheme with an improved diffusion strategy.
Fu, Chong; Chen, Jun-jie; Zou, Hao; Meng, Wei-hong; Zhan, Yong-feng; Yu, Ya-wen
2012-01-30
Chaos-based image cipher has been widely investigated over the last decade or so to meet the increasing demand for real-time secure image transmission over public networks. In this paper, an improved diffusion strategy is proposed to promote the efficiency of the most widely investigated permutation-diffusion type image cipher. By using the novel bidirectional diffusion strategy, the spreading process is significantly accelerated and hence the same level of security can be achieved with fewer overall encryption rounds. Moreover, to further enhance the security of the cryptosystem, a plain-text related chaotic orbit turbulence mechanism is introduced in diffusion procedure by perturbing the control parameter of the employed chaotic system according to the cipher-pixel. Extensive cryptanalysis has been performed on the proposed scheme using differential analysis, key space analysis, various statistical analyses and key sensitivity analysis. Results of our analyses indicate that the new scheme has a satisfactory security level with a low computational complexity, which renders it a good candidate for real-time secure image transmission applications.
Seo, Jung Woo; Lee, Sang Jin
2016-01-01
Weather information provides a safe working environment by contributing to the economic activity of the nation, and plays role of the prevention of natural disasters, which can cause large scaled casualties and damage of property. Especially during times of war, weather information plays a more important role than strategy, tactics and information about trends of the enemy. Also, it plays an essential role for the taking off and landing of fighter jet and the sailing of warships. If weather information, which plays a major role in national security and economy, gets misused for cyber terrorism resulting false weather information, it could be a huge threat for national security and the economy. We propose a plan to safely transmit the measured value from meteorological sensors through a meteorological telecommunication network in order to guarantee the confidentiality and integrity of the data despite cyber-attacks. Also, such a plan allows one to produce reliable weather forecasts by performing mutual authentication through authentication devices. To make sure of this, one can apply an Identity Based Signature to ensure the integrity of measured data, and transmit the encrypted weather information with mutual authentication about the authentication devices. There are merits of this research: It is not necessary to manage authentication certificates unlike the Public Key Infrastructure methodology, and it provides a powerful security measure with the capability to be realized in a small scale computing environment, such as the meteorological observation system due to the low burden on managing keys.
On the security of a new image encryption scheme based on chaotic map lattices.
Arroyo, David; Rhouma, Rhouma; Alvarez, Gonzalo; Li, Shujun; Fernandez, Veronica
2008-09-01
This paper reports a detailed cryptanalysis of a recently proposed encryption scheme based on the logistic map [A. Pisarchik et al., Chaos 16, 033118 (2006)]. Some problems are emphasized concerning the key space definition and the implementation of the cryptosystem using floating-point operations. It is also shown how it is possible to reduce considerably the key space through a ciphertext-only attack. Moreover, a timing attack allows for the estimation of part of the key due to the existent relationship between this part of the key and the encryption/decryption time. As a result, the main features of the cryptosystem do not satisfy the demands of secure communications. Some hints are offered to improve the cryptosystem under study according to those requirements.
Chaotic Image Encryption of Regions of Interest
NASA Astrophysics Data System (ADS)
Xiao, Di; Fu, Qingqing; Xiang, Tao; Zhang, Yushu
Since different regions of an image have different importance, therefore only the important information of the image regions, which the users are really interested in, needs to be encrypted and protected emphatically in some special multimedia applications. However, the regions of interest (ROI) are always some irregular parts, such as the face and the eyes. Assuming the bulk data in transmission without being damaged, we propose a chaotic image encryption algorithm for ROI. ROI with irregular shapes are chosen and detected arbitrarily. Then the chaos-based image encryption algorithm with scrambling, S-box and diffusion parts is used to encrypt the ROI. Further, the whole image is compressed with Huffman coding. At last, a message authentication code (MAC) of the compressed image is generated based on chaotic maps. The simulation results show that the encryption algorithm has a good security level and can resist various attacks. Moreover, the compression method improves the storage and transmission efficiency to some extent, and the MAC ensures the integrity of the transmission data.
A novel block encryption scheme based on chaos and an S-box for wireless sensor networks
NASA Astrophysics Data System (ADS)
Tong, Xiao-Jun; Wang, Zhu; Zuo, Ke
2012-02-01
The wireless sensor network (WSN) has been widely used in various fields, but it still remains in the preliminary discovery and research phase with a lack of various related mature technologies. Traditional encryption schemes are not suitable for wireless sensor networks due to intrinsic features of the nodes such as low energy, limited computation capability, and lack of storage resources. In this paper, we present a novel block encryption scheme based on the integer discretization of a chaotic map, the Feistel network structure, and an S-box. The novel scheme is fast, secure, has low resource consumption and is suitable for wireless sensor network node encryption schemes. The experimental tests are carried out with detailed analysis, showing that the novel block algorithm has a large key space, very good diffusion and disruptive performances, a strict avalanche effect, excellent statistical balance, and fast encryption speed. These features enable the encryption scheme to pass the SP800-22 test. Meanwhile, the analysis and the testing of speed, time, and storage space on the simulator platform show that this new encryption scheme is well able to hide data information in wireless sensor networks.
Aldossari, M; Alfalou, A; Brosseau, C
2014-09-22
This study presents and validates an optimized method of simultaneous compression and encryption designed to process images with close spectra. This approach is well adapted to the compression and encryption of images of a time-varying scene but also to static polarimetric images. We use the recently developed spectral fusion method [Opt. Lett.35, 1914-1916 (2010)] to deal with the close resemblance of the images. The spectral plane (containing the information to send and/or to store) is decomposed in several independent areas which are assigned according a specific way. In addition, each spectrum is shifted in order to minimize their overlap. The dual purpose of these operations is to optimize the spectral plane allowing us to keep the low- and high-frequency information (compression) and to introduce an additional noise for reconstructing the images (encryption). Our results show that not only can the control of the spectral plane enhance the number of spectra to be merged, but also that a compromise between the compression rate and the quality of the reconstructed images can be tuned. We use a root-mean-square (RMS) optimization criterion to treat compression. Image encryption is realized at different security levels. Firstly, we add a specific encryption level which is related to the different areas of the spectral plane, and then, we make use of several random phase keys. An in-depth analysis at the spectral fusion methodology is done in order to find a good trade-off between the compression rate and the quality of the reconstructed images. Our new proposal spectral shift allows us to minimize the image overlap. We further analyze the influence of the spectral shift on the reconstructed image quality and compression rate. The performance of the multiple-image optical compression and encryption method is verified by analyzing several video sequences and polarimetric images.
Smolders, Roel; Colles, Ann; Cornelis, Christa; Van Holderbeke, Mirja; Chovanova, Hana; Wildemeersch, Dirk; Mampaey, Maja; Van Campenhout, Karen
2014-12-15
Although well-established protocols are available for emergency services and first-responders in case of chemical release incidents, a well-developed system to monitor and safeguard public health was, until recently, lacking in Flanders. We therefore developed a decision support system (DSS) to aid public health officials in identifying the appropriate actions in case of incidents. Although the DSS includes human biomonitoring as one of its key instruments, it also goes well beyond this instrument alone. Also other, complementary, approaches that focus more on effect assessment using in vitro toxicity testing, indirect exposures through the food chain, and parallel means of data collection (e.g. through ecosurveillance or public consultation), are integrated in the Flemish approach. Even though the DSS is set up to provide a flexible and structured decision tree, the value of expert opinion is deemed essential to account for the many uncertainties associated with the early phases of technological incidents. When the DSS and the associated instruments will be fully operational, it will provide a valuable addition to the already available protocols, and will specifically safeguard public health interests.
NASA Astrophysics Data System (ADS)
Zhao, Shengmei; Wang, Le; Liang, Wenqiang; Cheng, Weiwen; Gong, Longyan
2015-10-01
In this paper, we propose a high performance optical encryption (OE) scheme based on computational ghost imaging (GI) with QR code and compressive sensing (CS) technique, named QR-CGI-OE scheme. N random phase screens, generated by Alice, is a secret key and be shared with its authorized user, Bob. The information is first encoded by Alice with QR code, and the QR-coded image is then encrypted with the aid of computational ghost imaging optical system. Here, measurement results from the GI optical system's bucket detector are the encrypted information and be transmitted to Bob. With the key, Bob decrypts the encrypted information to obtain the QR-coded image with GI and CS techniques, and further recovers the information by QR decoding. The experimental and numerical simulated results show that the authorized users can recover completely the original image, whereas the eavesdroppers can not acquire any information about the image even the eavesdropping ratio (ER) is up to 60% at the given measurement times. For the proposed scheme, the number of bits sent from Alice to Bob are reduced considerably and the robustness is enhanced significantly. Meantime, the measurement times in GI system is reduced and the quality of the reconstructed QR-coded image is improved.
Sui, Liansheng; Duan, Kuaikuai; Liang, Junli; Hei, Xinhong
2014-05-05
A double-image encryption is proposed based on the discrete fractional random transform and logistic maps. First, an enlarged image is composited from two original images and scrambled in the confusion process which consists of a number of rounds. In each round, the pixel positions of the enlarged image are relocated by using cat maps which are generated based on two logistic maps. Then the scrambled enlarged image is decomposed into two components. Second, one of two components is directly separated into two phase masks and the other component is used to derive the ciphertext image with stationary white noise distribution by using the cascaded discrete fractional random transforms generated based on the logistic map. The cryptosystem is asymmetric and has high resistance against to the potential attacks such as chosen plaintext attack, in which the initial values of logistic maps and the fractional orders are considered as the encryption keys while two decryption keys are produced in the encryption process and directly related to the original images. Simulation results and security analysis verify the feasibility and effectiveness of the proposed encryption scheme.
A novel image encryption algorithm based on chaos maps with Markov properties
NASA Astrophysics Data System (ADS)
Liu, Quan; Li, Pei-yue; Zhang, Ming-chao; Sui, Yong-xin; Yang, Huai-jiang
2015-02-01
In order to construct high complexity, secure and low cost image encryption algorithm, a class of chaos with Markov properties was researched and such algorithm was also proposed. The kind of chaos has higher complexity than the Logistic map and Tent map, which keeps the uniformity and low autocorrelation. An improved couple map lattice based on the chaos with Markov properties is also employed to cover the phase space of the chaos and enlarge the key space, which has better performance than the original one. A novel image encryption algorithm is constructed on the new couple map lattice, which is used as a key stream generator. A true random number is used to disturb the key which can dynamically change the permutation matrix and the key stream. From the experiments, it is known that the key stream can pass SP800-22 test. The novel image encryption can resist CPA and CCA attack and differential attack. The algorithm is sensitive to the initial key and can change the distribution the pixel values of the image. The correlation of the adjacent pixels can also be eliminated. When compared with the algorithm based on Logistic map, it has higher complexity and better uniformity, which is nearer to the true random number. It is also efficient to realize which showed its value in common use.
Wang, Xiaogang; Zhao, Daomu
2013-09-15
We propose a simple amplitude-phase retrieval attack free cryptosystem based on direct attack to phase-truncated Fourier-transform-based encryption using a random amplitude mask (RAM). The RAM that is not saved during the encryption provides extremely high security for the two private keys, and no iterative calculations are involved in the nonlinear encryption process. Lack of enough constraints makes the specific attack based on iterative amplitude-phase retrieval algorithms unusable. Numerical simulation results are given for testing the validity and security of the proposed approach.
Security of image encryption scheme based on multi-parameter fractional Fourier transform
NASA Astrophysics Data System (ADS)
Zhao, Tieyu; Ran, Qiwen; Yuan, Lin; Chi, Yingying; Ma, Jing
2016-10-01
Recently, multi-parameter fractional Fourier transform (MPFRFT) has been widely applied in the optics cryptosystem, which has attracted more and more researchers' attention. However, in further study we find a serious security problem on the MPFRFT which is the multi-choice of decryption key corresponding to an encryption key. The existence of multi-decryption-key hinders the application of this algorithm. We present a new generalized fractional Fourier transform, which can overcome the problem and enlarge the key space. The simulation results show that the proposed algorithm has higher security and key sensitivity.
Small Private Key PKS on an Embedded Microprocessor
Seo, Hwajeong; Kim, Jihyun; Choi, Jongseok; Park, Taehwan; Liu, Zhe; Kim, Howon
2014-01-01
Multivariate quadratic ( ) cryptography requires the use of long public and private keys to ensure a sufficient security level, but this is not favorable to embedded systems, which have limited system resources. Recently, various approaches to cryptography using reduced public keys have been studied. As a result of this, at CHES2011 (Cryptographic Hardware and Embedded Systems, 2011), a small public key scheme, was proposed, and its feasible implementation on an embedded microprocessor was reported at CHES2012. However, the implementation of a small private key scheme was not reported. For efficient implementation, random number generators can contribute to reduce the key size, but the cost of using a random number generator is much more complex than computing on modern microprocessors. Therefore, no feasible results have been reported on embedded microprocessors. In this paper, we propose a feasible implementation on embedded microprocessors for a small private key scheme using a pseudo-random number generator and hash function based on a block-cipher exploiting a hardware Advanced Encryption Standard (AES) accelerator. To speed up the performance, we apply various implementation methods, including parallel computation, on-the-fly computation, optimized logarithm representation, vinegar monomials and assembly programming. The proposed method reduces the private key size by about 99.9% and boosts signature generation and verification by 5.78% and 12.19% than previous results in CHES2012. PMID:24651722
Small private key MQPKS on an embedded microprocessor.
Seo, Hwajeong; Kim, Jihyun; Choi, Jongseok; Park, Taehwan; Liu, Zhe; Kim, Howon
2014-03-19
Multivariate quadratic (MQ) cryptography requires the use of long public and private keys to ensure a sufficient security level, but this is not favorable to embedded systems, which have limited system resources. Recently, various approaches to MQ cryptography using reduced public keys have been studied. As a result of this, at CHES2011 (Cryptographic Hardware and Embedded Systems, 2011), a small public key MQ scheme, was proposed, and its feasible implementation on an embedded microprocessor was reported at CHES2012. However, the implementation of a small private key MQ scheme was not reported. For efficient implementation, random number generators can contribute to reduce the key size, but the cost of using a random number generator is much more complex than computing MQ on modern microprocessors. Therefore, no feasible results have been reported on embedded microprocessors. In this paper, we propose a feasible implementation on embedded microprocessors for a small private key MQ scheme using a pseudo-random number generator and hash function based on a block-cipher exploiting a hardware Advanced Encryption Standard (AES) accelerator. To speed up the performance, we apply various implementation methods, including parallel computation, on-the-fly computation, optimized logarithm representation, vinegar monomials and assembly programming. The proposed method reduces the private key size by about 99.9% and boosts signature generation and verification by 5.78% and 12.19% than previous results in CHES2012.
Identity-Based Verifiably Encrypted Signatures without Random Oracles
NASA Astrophysics Data System (ADS)
Zhang, Lei; Wu, Qianhong; Qin, Bo
Fair exchange protocol plays an important role in electronic commerce in the case of exchanging digital contracts. Verifiably encrypted signatures provide an optimistic solution to these scenarios with an off-line trusted third party. In this paper, we propose an identity-based verifiably encrypted signature scheme. The scheme is non-interactive to generate verifiably encrypted signatures and the resulting encrypted signature consists of only four group elements. Based on the computational Diffie-Hellman assumption, our scheme is proven secure without using random oracles. To the best of our knowledge, this is the first identity-based verifiably encrypted signature scheme provably secure in the standard model.
An optical authentication system based on encryption technique and multimodal biometrics
NASA Astrophysics Data System (ADS)
Yuan, Sheng; Zhang, Tong; Zhou, Xin; Liu, Xuemei; Liu, Mingtang
2013-12-01
A major concern nowadays for a biometric credential management system is its potential vulnerability to protect its information sources. To prevent a genuine user's templates from both internal and external threats, a novel and simple method combined optical encryption with multimodal biometric authentication technique is proposed. In this method, the standard biometric templates are generated real-timely by the verification keys owned by legal user so that they are unnecessary to be stored in a database. Compared with the traditional recognition algorithms, storage space and matching time are greatly saved. In addition, the verification keys are difficult to be forged due to the utilization of optical encryption technique. Although the verification keys are lost or stolen, they are useless for others in absence of the legal owner's biometric. A series of numerical simulations are performed to demonstrate the feasibility and performance of this method.
Degradative encryption: An efficient way to protect SPIHT compressed images
NASA Astrophysics Data System (ADS)
Xiang, Tao; Qu, Jinyu; Yu, Chenyun; Fu, Xinwen
2012-11-01
Degradative encryption, a new selective image encryption paradigm, is proposed to encrypt only a small part of image data to make the detail blurred but keep the skeleton discernible. The efficiency is further optimized by combining compression and encryption. A format-compliant degradative encryption algorithm based on set partitioning in hierarchical trees (SPIHT) is then proposed, and the scheme is designed to work in progressive mode for gaining a tradeoff between efficiency and security. Extensive experiments are conducted to evaluate the strength and efficiency of the scheme, and it is found that less than 10% data need to be encrypted for a secure degradation. In security analysis, the scheme is verified to be immune to cryptographic attacks as well as those adversaries utilizing image processing techniques. The scheme can find its wide applications in online try-and-buy service on mobile devices, searchable multimedia encryption in cloud computing, etc.
Calculation of key reduction for B92 QKD protocol
NASA Astrophysics Data System (ADS)
Mehic, Miralem; Partila, Pavol; Tovarek, Jaromir; Voznak, Miroslav
2015-05-01
It is well known that Quantum Key Distribution (QKD) can be used with the highest level of security for distribution of the secret key, which is further used for symmetrical encryption. B92 is one of the oldest QKD protocols. It uses only two non-orthogonal states, each one coding for one bit-value. It is much faster and simpler when compared to its predecessors, but with the idealized maximum efficiencies of 25% over the quantum channel. B92 consists of several phases in which initial key is significantly reduced: secret key exchange, extraction of the raw key (sifting), error rate estimation, key reconciliation and privacy amplification. QKD communication is performed over two channels: the quantum channel and the classical public channel. In order to prevent a man-in-the-middle attack and modification of messages on the public channel, authentication of exchanged values must be performed. We used Wegman-Carter authentication because it describes an upper bound for needed symmetric authentication key. We explained the reduction of the initial key in each of QKD phases.
Alfalou, A; Brosseau, C
2010-06-01
We report on an algorithm to compress and encrypt simultaneously multiple images (target images). This method, which is based upon a specific spectral multiplexing (fusion without overlapping) of the multiple images, aims to achieve a single encrypted image, at the output plane of our system, that contains all information needed to reconstruct the target images. For that purpose, we divide the Fourier plane of the image to transmit into two types of area, i.e., specific and common areas to each target image. A segmentation criterion taking into account the rms duration of each target image spectrum is proposed. This approach, which consists of merging the input target images together (in the Fourier plane) allows us to reduce the information to be stored and/or transmitted (compression) and induce noise on the output image (encryption). To achieve a good encryption level, a first key image (containing biometric information and providing the intellectual property of the target images) is used. A second encryption key is inserted in the Fourier plane to ensure a relevant phase distribution of the different merged spectra. We also discuss how the encoding information can be optimized by minimizing the number of bits required to encode each pixel.
An Efficient Image Encryption Scheme Based on a Peter De Jong Chaotic Map and a RC4 Stream Cipher
NASA Astrophysics Data System (ADS)
Hanchinamani, Gururaj; Kulkarni, Linganagouda
2015-09-01
Security is a vital issue in communication and storage of the images and encryption is one of the ways to ensure the security. This paper proposes an efficient image encryption scheme based on a Peter De Jong chaotic map and a RC4 stream cipher. A Peter De Jong map is employed to determine the initial keys for the RC4 stream generator and also during permutation stage. The RC4 stream generator is utilized to generate the pseudo random numbers for the pixel value rotation and diffusion operations. Each encryption round is comprised of three stages: permutation, pixel value rotation and diffusion. The permutation is based on scrambling the rows and columns, in addition, circular rotations of the rows and columns in alternate orientations. The second stage circularly rotates each and every pixel value by utilizing M × N pseudo random numbers. The last stage carries out the diffusion twice by scanning the image in two different ways. Each of the two diffusions accomplishes the diffusion in two orientations (forward and backward) with two previously diffused pixels and two pseudo random numbers. The security and performance of the proposed method is assessed thoroughly by using key space, statistical, differential, entropy and performance analysis. Moreover, two rounds of the call to the encrypt function provide the sufficient security. The experimental results show that the proposed encryption scheme is computationally fast with high security.
Madsen, Heidi Holst; Madsen, Dicte; Gauffriau, Marianne
2016-01-01
Unique identifiers (UID) are seen as an effective key to match identical publications across databases or identify duplicates in a database. The objective of the present study is to investigate how well UIDs work as match keys in the integration between Pure and SciVal, based on a case with publications from the health sciences. We evaluate the matching process based on information about coverage, precision, and characteristics of publications matched versus not matched with UIDs as the match keys. We analyze this information to detect errors, if any, in the matching process. As an example we also briefly discuss how publication sets formed by using UIDs as the match keys may affect the bibliometric indicators number of publications, number of citations, and the average number of citations per publication. The objective is addressed in a literature review and a case study. The literature review shows that only a few studies evaluate how well UIDs work as a match key. From the literature we identify four error types: Duplicate digital object identifiers (DOI), incorrect DOIs in reference lists and databases, DOIs not registered by the database where a bibliometric analysis is performed, and erroneous optical or special character recognition. The case study explores the use of UIDs in the integration between the databases Pure and SciVal. Specifically journal publications in English are matched between the two databases. We find all error types except erroneous optical or special character recognition in our publication sets. In particular the duplicate DOIs constitute a problem for the calculation of bibliometric indicators as both keeping the duplicates to improve the reliability of citation counts and deleting them to improve the reliability of publication counts will distort the calculation of average number of citations per publication. The use of UIDs as a match key in citation linking is implemented in many settings, and the availability of UIDs may become
Madsen, Heidi Holst; Madsen, Dicte; Gauffriau, Marianne
2016-01-01
Unique identifiers (UID) are seen as an effective key to match identical publications across databases or identify duplicates in a database. The objective of the present study is to investigate how well UIDs work as match keys in the integration between Pure and SciVal, based on a case with publications from the health sciences. We evaluate the matching process based on information about coverage, precision, and characteristics of publications matched versus not matched with UIDs as the match keys. We analyze this information to detect errors, if any, in the matching process. As an example we also briefly discuss how publication sets formed by using UIDs as the match keys may affect the bibliometric indicators number of publications, number of citations, and the average number of citations per publication. The objective is addressed in a literature review and a case study. The literature review shows that only a few studies evaluate how well UIDs work as a match key. From the literature we identify four error types: Duplicate digital object identifiers (DOI), incorrect DOIs in reference lists and databases, DOIs not registered by the database where a bibliometric analysis is performed, and erroneous optical or special character recognition. The case study explores the use of UIDs in the integration between the databases Pure and SciVal. Specifically journal publications in English are matched between the two databases. We find all error types except erroneous optical or special character recognition in our publication sets. In particular the duplicate DOIs constitute a problem for the calculation of bibliometric indicators as both keeping the duplicates to improve the reliability of citation counts and deleting them to improve the reliability of publication counts will distort the calculation of average number of citations per publication. The use of UIDs as a match key in citation linking is implemented in many settings, and the availability of UIDs may become
Double-image encryption using discrete fractional random transform and logistic maps
NASA Astrophysics Data System (ADS)
Sui, Liansheng; Lu, Haiwei; Wang, Zhanmin; Sun, Qindong
2014-05-01
A double-image encryption is proposed based on the discrete fractional random transform and logistic maps. Firstly, an enlarged image is composited from two original plaintexts, in which the pixel positions are relocated and the intensity values are changed by a chaotic confusion-diffusion process, and then two scrambled plaintexts are recovered from the enlarged image. Secondly, the two scrambled plaintexts are encoded into the phase and amplitude part of a complex function which is encrypted into a ciphertext with stationary white noise distribution by using the discrete fractional random transform generated based on logistic map. Not only the initial values of the logistic maps used in the cryptosystem but also the phase distribution produced in the encryption process can be used as private keys, which makes the proposed scheme has the characteristic of asymmetric encryption technique and high resistance against to the conventional attacks such as chosen plaintext attack, ciphertext-only attack. Simulation results and security analysis verify the feasibility and effectiveness of the proposed method.
FORESEE: Fully Outsourced secuRe gEnome Study basEd on homomorphic Encryption
2015-01-01
Background The increasing availability of genome data motivates massive research studies in personalized treatment and precision medicine. Public cloud services provide a flexible way to mitigate the storage and computation burden in conducting genome-wide association studies (GWAS). However, data privacy has been widely concerned when sharing the sensitive information in a cloud environment. Methods We presented a novel framework (FORESEE: Fully Outsourced secuRe gEnome Study basEd on homomorphic Encryption) to fully outsource GWAS (i.e., chi-square statistic computation) using homomorphic encryption. The proposed framework enables secure divisions over encrypted data. We introduced two division protocols (i.e., secure errorless division and secure approximation division) with a trade-off between complexity and accuracy in computing chi-square statistics. Results The proposed framework was evaluated for the task of chi-square statistic computation with two case-control datasets from the 2015 iDASH genome privacy protection challenge. Experimental results show that the performance of FORESEE can be significantly improved through algorithmic optimization and parallel computation. Remarkably, the secure approximation division provides significant performance gain, but without missing any significance SNPs in the chi-square association test using the aforementioned datasets. Conclusions Unlike many existing HME based studies, in which final results need to be computed by the data owner due to the lack of the secure division operation, the proposed FORESEE framework support complete outsourcing to the cloud and output the final encrypted chi-square statistics. PMID:26733391
VLSI design of an RSA encryption/decryption chip using systolic array based architecture
NASA Astrophysics Data System (ADS)
Sun, Chi-Chia; Lin, Bor-Shing; Jan, Gene Eu; Lin, Jheng-Yi
2016-09-01
This article presents the VLSI design of a configurable RSA public key cryptosystem supporting the 512-bit, 1024-bit and 2048-bit based on Montgomery algorithm achieving comparable clock cycles of current relevant works but with smaller die size. We use binary method for the modular exponentiation and adopt Montgomery algorithm for the modular multiplication to simplify computational complexity, which, together with the systolic array concept for electric circuit designs effectively, lower the die size. The main architecture of the chip consists of four functional blocks, namely input/output modules, registers module, arithmetic module and control module. We applied the concept of systolic array to design the RSA encryption/decryption chip by using VHDL hardware language and verified using the TSMC/CIC 0.35 m 1P4 M technology. The die area of the 2048-bit RSA chip without the DFT is 3.9 × 3.9 mm2 (4.58 × 4.58 mm2 with DFT). Its average baud rate can reach 10.84 kbps under a 100 MHz clock.
Color image encryption based on hybrid hyper-chaotic system and cellular automata
NASA Astrophysics Data System (ADS)
Yaghouti Niyat, Abolfazl; Moattar, Mohammad Hossein; Niazi Torshiz, Masood
2017-03-01
This paper proposes an image encryption scheme based on Cellular Automata (CA). CA is a self-organizing structure with a set of cells in which each cell is updated by certain rules that are dependent on a limited number of neighboring cells. The major disadvantages of cellular automata in cryptography include limited number of reversal rules and inability to produce long sequences of states by these rules. In this paper, a non-uniform cellular automata framework is proposed to solve this problem. This proposed scheme consists of confusion and diffusion steps. In confusion step, the positions of the original image pixels are replaced by chaos mapping. Key image is created using non-uniform cellular automata and then the hyper-chaotic mapping is used to select random numbers from the image key for encryption. The main contribution of the paper is the application of hyper chaotic functions and non-uniform CA for robust key image generation. Security analysis and experimental results show that the proposed method has a very large key space and is resistive against noise and attacks. The correlation between adjacent pixels in the encrypted image is reduced and the amount of entropy is equal to 7.9991 which is very close to 8 which is ideal.
Three-dimensional information hierarchical encryption based on computer-generated holograms
NASA Astrophysics Data System (ADS)
Kong, Dezhao; Shen, Xueju; Cao, Liangcai; Zhang, Hao; Zong, Song; Jin, Guofan
2016-12-01
A novel approach for encrypting three-dimensional (3-D) scene information hierarchically based on computer-generated holograms (CGHs) is proposed. The CGHs of the layer-oriented 3-D scene information are produced by angular-spectrum propagation algorithm at different depths. All the CGHs are then modulated by different chaotic random phase masks generated by the logistic map. Hierarchical encryption encoding is applied when all the CGHs are accumulated one by one, and the reconstructed volume of the 3-D scene information depends on permissions of different users. The chaotic random phase masks could be encoded into several parameters of the chaotic sequences to simplify the transmission and preservation of the keys. Optical experiments verify the proposed method and numerical simulations show the high key sensitivity, high security, and application flexibility of the method.
High-performance multimedia encryption system based on chaos.
Hasimoto-Beltrán, Rogelio
2008-06-01
Current chaotic encryption systems in the literature do not fulfill security and performance demands for real-time multimedia communications. To satisfy these demands, we propose a generalized symmetric cryptosystem based on N independently iterated chaotic maps (N-map array) periodically perturbed with a three-level perturbation scheme and a double feedback (global and local) to increase the system's robustness to attacks. The first- and second-level perturbations make cryptosystem extremely sensitive to changes in the plaintext data since the system's output itself (ciphertext global feedback) is used in the perturbation process. Third-level perturbation is a system reset, in which the system-key and chaotic maps are replaced for totally new values. An analysis of the proposed scheme regarding its vulnerability to attacks, statistical properties, and implementation performance is presented. To the best of our knowledge we provide a secure cryptosystem with one of the highest levels of performance for real-time multimedia communications.
High-performance multimedia encryption system based on chaos
NASA Astrophysics Data System (ADS)
Hasimoto-Beltrán, Rogelio
2008-06-01
Current chaotic encryption systems in the literature do not fulfill security and performance demands for real-time multimedia communications. To satisfy these demands, we propose a generalized symmetric cryptosystem based on N independently iterated chaotic maps (N-map array) periodically perturbed with a three-level perturbation scheme and a double feedback (global and local) to increase the system's robustness to attacks. The first- and second-level perturbations make cryptosystem extremely sensitive to changes in the plaintext data since the system's output itself (ciphertext global feedback) is used in the perturbation process. Third-level perturbation is a system reset, in which the system-key and chaotic maps are replaced for totally new values. An analysis of the proposed scheme regarding its vulnerability to attacks, statistical properties, and implementation performance is presented. To the best of our knowledge we provide a secure cryptosystem with one of the highest levels of performance for real-time multimedia communications.
Color image encryption based on paired interpermuting planes
NASA Astrophysics Data System (ADS)
Zhang, Wei; Yu, Hai; Zhu, Zhi-liang
2015-03-01
A number of chaos-based image encryption algorithms have been proposed in recent years, and most of them employ confusion-diffusion architecture. This paper presents a new confusion scheme based on paired interpermuting planes. In the proposed new confusion operation, an "exchange and random access strategy" is employed to replace the traditional confusion operations. The efficiency of the proposed scheme was analyzed by evaluating its histogram distribution, its correlation coefficients, its ability to resist differential attacks, its ability to retain information (entropy analysis), its computational speed, and its ability to guarantee the security of its key scheme. Simulations have been carried out and the results confirmed the superior security and computing speed of our scheme compared to other comparable algorithms.
Sparse-based multispectral image encryption via ptychography
NASA Astrophysics Data System (ADS)
Rawat, Nitin; Shi, Yishi; Kim, Byoungho; Lee, Byung-Geun
2015-12-01
Recently, we proposed a model of securing a ptychography-based monochromatic image encryption system via the classical Photon-counting imaging (PCI) technique. In this study, we examine a single-channel multispectral sparse-based photon-counting ptychography imaging (SMPI)-based cryptosystem. A ptychography-based cryptosystem creates a complex object wave field, which can be reconstructed by a series of diffraction intensity patterns through an aperture movement. The PCI sensor records only a few complex Bayer patterned samples that have been utilized in the decryption process. Sparse sensing and nonlinear properties of the classical PCI system, together with the scanning probes, enlarge the key space, and such a combination therefore enhances the system's security. We demonstrate that the sparse samples have adequate information for image decryption, as well as information authentication by means of optical correlation.
Restricted Authentication and Encryption for Cyber-physical Systems
Kirkpatrick, Michael S; Bertino, Elisa; Sheldon, Frederick T
2009-01-01
Cyber-physical systems (CPS) are characterized by the close linkage of computational resources and physical devices. These systems can be deployed in a number of critical infrastructure settings. As a result, the security requirements of CPS are different than traditional computing architectures. For example, critical functions must be identified and isolated from interference by other functions. Similarly, lightweight schemes may be required, as CPS can include devices with limited computing power. One approach that offers promise for CPS security is the use of lightweight, hardware-based authentication. Specifically, we consider the use of Physically Unclonable Functions (PUFs) to bind an access request to specific hardware with device-specific keys. PUFs are implemented in hardware, such as SRAM, and can be used to uniquely identify the device. This technology could be used in CPS to ensure location-based access control and encryption, both of which would be desirable for CPS implementations.
A New Quaternion-Based Encryption Method for DICOM Images.
Dzwonkowski, Mariusz; Papaj, Michal; Rykaczewski, Roman
2015-11-01
In this paper, a new quaternion-based lossless encryption technique for digital image and communication on medicine (DICOM) images is proposed. We have scrutinized and slightly modified the concept of the DICOM network to point out the best location for the proposed encryption scheme, which significantly improves speed of DICOM images encryption in comparison with those originally embedded into DICOM advanced encryption standard and triple data encryption standard algorithms. The proposed algorithm decomposes a DICOM image into two 8-bit gray-tone images in order to perform encryption. The algorithm implements Feistel network like the scheme proposed by Sastry and Kumar. It uses special properties of quaternions to perform rotations of data sequences in 3D space for each of the cipher rounds. The images are written as Lipschitz quaternions, and modular arithmetic was implemented for operations with the quaternions. A computer-based analysis has been carried out, and the obtained results are shown at the end of this paper.
Image encryption using P-Fibonacci transform and decomposition
NASA Astrophysics Data System (ADS)
Zhou, Yicong; Panetta, Karen; Agaian, Sos; Chen, C. L. Philip
2012-03-01
Image encryption is an effective method to protect images or videos by transferring them into unrecognizable formats for different security purposes. To improve the security level of bit-plane decomposition based encryption approaches, this paper introduces a new image encryption algorithm by using a combination of parametric bit-plane decomposition along with bit-plane shuffling and resizing, pixel scrambling and data mapping. The algorithm utilizes the Fibonacci P-code for image bit-plane decomposition and the 2D P-Fibonacci transform for image encryption because they are parameter dependent. Any new or existing method can be used for shuffling the order of the bit-planes. Simulation analysis and comparisons are provided to demonstrate the algorithm's performance for image encryption. Security analysis shows the algorithm's ability against several common attacks. The algorithm can be used to encrypt images, biometrics and videos.
Triple-image encryption based on phase-truncated Fresnel transform and basic vector operation.
Pan, Xuemei; Meng, Xiangfeng; Yang, Xiulun; Wang, Yurong; Peng, Xiang; He, Wenqi; Dong, Guoyan; Chen, Hongyi
2015-10-01
A triple-image encryption method is proposed that is based on phase-truncated Fresnel transform (PTFT), basic vector composition, and XOR operation. In the encryption process, two random phase masks, with one each placed at the input plane and the transform plane, are generated by basic vector resolution operations over the first and the second plaintext images, and then a ciphered image in the input plane is fabricated by XOR encoding for the third plaintext image. When the cryptosystem is illuminated by an on-axis plane, assisted by PTFT, the ciphered image is finally encrypted into an amplitude-only noise-like image in the output plane. During decryption, possessing the correct private key, decryption keys, and the assistant geometrical parameter keys, and placing them at the corresponding correct positions, the original three plaintext images can be successfully decrypted by inverse PTFT, basic vector composition, and XOR decoding. Theoretical analysis and numerical simulations both verify the feasibility of the proposed method.
Privacy protection in HealthGrid: distributing encryption management over the VO.
Torres, Erik; de Alfonso, Carlos; Blanquer, Ignacio; Hernández, Vicente
2006-01-01
Grid technologies have proven to be very successful in tackling challenging problems in which data access and processing is a bottleneck. Notwithstanding the benefits that Grid technologies could have in Health applications, privacy leakages of current DataGrid technologies due to the sharing of data in VOs and the use of remote resources, compromise its widespreading. Privacy control for Grid technology has become a key requirement for the adoption of Grids in the Healthcare sector. Encrypted storage of confidential data effectively reduces the risk of disclosure. A self-enforcing scheme for encrypted data storage can be achieved by combining Grid security systems with distributed key management and classical cryptography techniques. Virtual Organizations, as the main unit of user management in Grid, can provide a way to organize key sharing, access control lists and secure encryption management. This paper provides programming models and discusses the value, costs and behavior of such a system implemented on top of one of the latest Grid middlewares. This work is partially funded by the Spanish Ministry of Science and Technology in the frame of the project Investigación y Desarrollo de Servicios GRID: Aplicación a Modelos Cliente-Servidor, Colaborativos y de Alta Productividad, with reference TIC2003-01318.
NASA Astrophysics Data System (ADS)
Zhao, Hongjie; Zhong, Zhi; Fang, Weiwei; Xie, Hong; Zhang, Yabin; Shan, Mingguang
2016-09-01
A double-image encryption method is reported using chaotic maps, nonlinear non-DC joint transform correlator (JTC), and fractional Fourier transform (FrFT). The double images are converted into the amplitude and phase of a synthesized function through the application of chaotic pixel scrambling. The synthesized function bonded with a chaotic random phase mask (CRPM) and another different CRPM serve as the input signal of the JTC architecture in the fractional Fourier domain to obtain a real-valued encrypted image. The nonlinear and non-DC operation is also done to improve the security and decrypted image quality. The parameters in joint FrFT correlator and chaotic map serve as the encrypted keys. Numerical simulations have been done to demonstrate the feasibility and validity of this algorithm.
Deepan, B; Quan, C; Wang, Y; Tay, C J
2014-07-10
In this paper, a new multiple-image encryption and decryption technique that utilizes the compressive sensing (CS) concept along with a double-random phase encryption (DRPE) has been proposed. The space multiplexing method is employed for integrating multiple-image data. The method, which results in a nonlinear encryption system, is able to overcome the vulnerability of classical DRPE. The CS technique and space multiplexing are able to provide additional key space in the proposed method. A numerical experiment of the proposed method is implemented and the results show that the proposed method has good accuracy and is more robust than classical DRPE. The proposed system is also employed against chosen-plaintext attacks and it is found that the inclusion of compressive sensing enhances robustness against the attacks.
NASA Astrophysics Data System (ADS)
Li, Yueping; Wang, Chunhua; Chen, Hua
2017-03-01
Recently, a number of chaos-based image encryption algorithms that use low-dimensional chaotic map and permutation-diffusion architecture have been proposed. However, low-dimensional chaotic map is less safe than high-dimensional chaotic system. And permutation process is independent of plaintext and diffusion process. Therefore, they cannot resist efficiently the chosen-plaintext attack and chosen-ciphertext attack. In this paper, we propose a hyper-chaos-based image encryption algorithm. The algorithm adopts a 5-D multi-wing hyper-chaotic system, and the key stream generated by hyper-chaotic system is related to the original image. Then, pixel-level permutation and bit-level permutation are employed to strengthen security of the cryptosystem. Finally, a diffusion operation is employed to change pixels. Theoretical analysis and numerical simulations demonstrate that the proposed algorithm is secure and reliable for image encryption.
Novel permutation measures for image encryption algorithms
NASA Astrophysics Data System (ADS)
Abd-El-Hafiz, Salwa K.; AbdElHaleem, Sherif H.; Radwan, Ahmed G.
2016-10-01
This paper proposes two measures for the evaluation of permutation techniques used in image encryption. First, a general mathematical framework for describing the permutation phase used in image encryption is presented. Using this framework, six different permutation techniques, based on chaotic and non-chaotic generators, are described. The two new measures are, then, introduced to evaluate the effectiveness of permutation techniques. These measures are (1) Percentage of Adjacent Pixels Count (PAPC) and (2) Distance Between Adjacent Pixels (DBAP). The proposed measures are used to evaluate and compare the six permutation techniques in different scenarios. The permutation techniques are applied on several standard images and the resulting scrambled images are analyzed. Moreover, the new measures are used to compare the permutation algorithms on different matrix sizes irrespective of the actual parameters used in each algorithm. The analysis results show that the proposed measures are good indicators of the effectiveness of the permutation technique.
Steganography and encrypting based on immunochemical systems.
Kim, Kyung-Woo; Bocharova, Vera; Halámek, Jan; Oh, Min-Kyu; Katz, Evgeny
2011-05-01
Steganography and encrypting were demonstrated with immuno-specific systems. IgG-proteins were used as invisible ink developed with complementary antibodies labeled with enzymes producing color spots. The information security was achieved by mixing the target protein-antigens used for the text encoding with masking proteins of similar composition but having different bioaffinity. Two different texts were simultaneously encoded by using two different encoding proteins in a mixture. Various encrypting techniques were exemplified with the immuno-systems used for the steganography. Future use of the developed approach for information protection and watermark-technology was proposed. Scaling down the encoded text to a micro-size is feasible with the use of nanotechnology.
Chaotic substitution for highly autocorrelated data in encryption algorithm
NASA Astrophysics Data System (ADS)
Anees, Amir; Siddiqui, Adil Masood; Ahmed, Fawad
2014-09-01
This paper addresses the major drawback of substitution-box in highly auto-correlated data and proposes a novel chaotic substitution technique for encryption algorithm to sort the problem. Simulation results reveal that the overall strength of the proposed technique for encryption is much stronger than most of the existing encryption techniques. Furthermore, few statistical security analyses have also been done to show the strength of anticipated algorithm.
15 CFR 742.15 - Encryption items.
Code of Federal Regulations, 2011 CFR
2011-01-01
... encryption software are distinguished from controls on other software regulated under the EAR. (a) Licensing... items (“EI”) classified under ECCN 5A002.a.1, a.2, a.5, a.6 and a.9; 5D002.a or c.1 for equipment... items may be exported under the provisions of License Exception ENC set forth in § 740.17 of the...
Research on medical image encryption in telemedicine systems.
Dai, Yin; Wang, Huanzhen; Zhou, Zixia; Jin, Ziyi
2016-04-29
Recently, advances in computers and high-speed communication tools have led to enhancements in remote medical consultation research. Laws in some localities require hospitals to encrypt patient information (including images of the patient) before transferring the data over a network. Therefore, developing suitable encryption algorithms is quite important for modern medicine. This paper demonstrates a digital image encryption algorithm based on chaotic mapping, which uses the no-period and no-convergence properties of a chaotic sequence to create image chaos and pixel averaging. Then, the chaotic sequence is used to encrypt the image, thereby improving data security. With this method, the security of data and images can be improved.
Boivin, Antoine; Lehoux, Pascale; Burgers, Jako; Grol, Richard
2014-01-01
Context In the past 50 years, individual patient involvement at the clinical consultation level has received considerable attention. More recently, patients and the public have increasingly been involved in collective decisions concerning the improvement of health care and policymaking. However, rigorous evaluation guiding the development and implementation of effective public involvement interventions is lacking. This article describes those key ingredients likely to affect public members’ ability to deliberate productively with professionals and influence collective health care choices. Method We conducted a trial process evaluation of public involvement in setting priorities for health care improvement. In all, 172 participants (including 83 patients and public members and 89 professionals) from 6 Health and Social Services Centers in Canada participated in the trial. We videorecorded 14 one-day meetings, and 2 nonparticipant observers took structured notes. Using qualitative analysis, we show how public members influenced health care improvement priorities. Findings Legitimacy, credibility, and power explain the variations in the public members’ influence. Their credibility was supported by their personal experience as patients and caregivers, the provision of a structured preparation meeting, and access to population-based data from their community. Legitimacy was fostered by the recruitment of a balanced group of participants and by the public members’ opportunities to draw from one another's experience. The combination of small-group deliberations, wider public consultation, and a moderation style focused on effective group process helped level out the power differences between professionals and the public. The engagement of key stakeholders in the intervention design and implementation helped build policy support for public involvement. Conclusions A number of interacting active ingredients structure and foster the public's legitimacy, credibility
NASA Astrophysics Data System (ADS)
Kadhem, Hasan; Amagasa, Toshiyuki; Kitagawa, Hiroyuki
Encryption can provide strong security for sensitive data against inside and outside attacks. This is especially true in the “Database as Service” model, where confidentiality and privacy are important issues for the client. In fact, existing encryption approaches are vulnerable to a statistical attack because each value is encrypted to another fixed value. This paper presents a novel database encryption scheme called MV-OPES (Multivalued — Order Preserving Encryption Scheme), which allows privacy-preserving queries over encrypted databases with an improved security level. Our idea is to encrypt a value to different multiple values to prevent statistical attacks. At the same time, MV-OPES preserves the order of the integer values to allow comparison operations to be directly applied on encrypted data. Using calculated distance (range), we propose a novel method that allows a join query between relations based on inequality over encrypted values. We also present techniques to offload query execution load to a database server as much as possible, thereby making a better use of server resources in a database outsourcing environment. Our scheme can easily be integrated with current database systems as it is designed to work with existing indexing structures. It is robust against statistical attack and the estimation of true values. MV-OPES experiments show that security for sensitive data can be achieved with reasonable overhead, establishing the practicability of the scheme.
Numerical implementation of the multiple image optical compression and encryption technique
NASA Astrophysics Data System (ADS)
Ouerhani, Y.; Aldossari, M.; Alfalou, A.; Brosseau, C.
2015-03-01
In this study, we propose a numerical implementation (using a GPU) of an optimized multiple image compression and encryption technique. We first introduce the double optimization procedure for spectrally multiplexing multiple images. This technique is adapted, for a numerical implementation, from a recently proposed optical setup implementing the Fourier transform (FT)1. The new analysis technique is a combination of a spectral fusion based on the properties of FT, a specific spectral filtering, and a quantization of the remaining encoded frequencies using an optimal number of bits. The spectral plane (containing the information to send and/or to store) is decomposed in several independent areas which are assigned according a specific way. In addition, each spectrum is shifted in order to minimize their overlap. The dual purpose of these operations is to optimize the spectral plane allowing us to keep the low- and high-frequency information (compression) and to introduce an additional noise for reconstructing the images (encryption). Our results show that not only can the control of the spectral plane enhance the number of spectra to be merged, but also that a compromise between the compression rate and the quality of the reconstructed images can be tuned. Spectrally multiplexing multiple images defines a first level of encryption. A second level of encryption based on a real key image is used to reinforce encryption. Additionally, we are concerned with optimizing the compression rate by adapting the size of the spectral block to each target image and decreasing the number of bits required to encode each block. This size adaptation is realized by means of the root-mean-square (RMS) time-frequency criterion2. We have found that this size adaptation provides a good trade-off between bandwidth of spectral plane and number of reconstructed output images3. Secondly, the encryption rate is improved by using a real biometric key and randomly changing the rotation angle of
Security-enhanced chaos communication with time-delay signature suppression and phase encryption.
Xue, Chenpeng; Jiang, Ning; Lv, Yunxin; Wang, Chao; Li, Guilan; Lin, Shuqing; Qiu, Kun
2016-08-15
A security-enhanced chaos communication scheme with time delay signature (TDS) suppression and phase-encrypted feedback light is proposed, in virtue of dual-loop feedback with independent high-speed phase modulation. We numerically investigate the property of TDS suppression in the intensity and phase space and quantitatively discuss security of the proposed system by calculating the bit error rate of eavesdroppers who try to crack the system by directly filtering the detected signal or by using a similar semiconductor laser to synchronize the link signal and extract the data. The results show that TDS embedded in the chaotic carrier can be well suppressed by properly setting the modulation frequency, which can keep the time delay a secret from the eavesdropper. Moreover, because the feedback light is encrypted, without the accurate time delay and key, the eavesdropper cannot reconstruct the symmetric operation conditions and decode the correct data.
A novel chaotic block image encryption algorithm based on dynamic random growth technique
NASA Astrophysics Data System (ADS)
Wang, Xingyuan; Liu, Lintao; Zhang, Yingqian
2015-03-01
This paper proposes a new block image encryption scheme based on hybrid chaotic maps and dynamic random growth technique. Since cat map is periodic and can be easily cracked by chosen plaintext attack, we use cat map in another securer way, which can completely eliminate the cyclical phenomenon and resist chosen plaintext attack. In the diffusion process, an intermediate parameter is calculated according to the image block. The intermediate parameter is used as the initial parameter of chaotic map to generate random data stream. In this way, the generated key streams are dependent on the plaintext image, which can resist the chosen plaintext attack. The experiment results prove that the proposed encryption algorithm is secure enough to be used in image transmission systems.
Three-dimensional scene encryption and display based on computer-generated holograms.
Kong, Dezhao; Cao, Liangcai; Jin, Guofan; Javidi, Bahram
2016-10-10
An optical encryption and display method for a three-dimensional (3D) scene is proposed based on computer-generated holograms (CGHs) using a single phase-only spatial light modulator. The 3D scene is encoded as one complex Fourier CGH. The Fourier CGH is then decomposed into two phase-only CGHs with random distributions by the vector stochastic decomposition algorithm. Two CGHs are interleaved as one final phase-only CGH for optical encryption and reconstruction. The proposed method can support high-level nonlinear optical 3D scene security and complex amplitude modulation of the optical field. The exclusive phase key offers strong resistances of decryption attacks. Experimental results demonstrate the validity of the novel method.
Quantum Image Encryption and Decryption Algorithms Based on Quantum Image Geometric Transformations
NASA Astrophysics Data System (ADS)
Zhou, Ri-Gui; Wu, Qian; Zhang, Man-Qun; Shen, Chen-Yi
2013-06-01
Cryptography is the essential subject for network information security to protect important data. Although following the symmetric cryptosystem for which the participations in the communication keep exactly the same keys, the special for the encryption and decryption algorithms proposed in this paper lays in the operational objectives, the quantum image. Firstly, extracts the properties of gray-scale and position from the quantum gray-scale image which the storage expression of image in quantum states is achieved. Along with the geometric transformations in classical images, this article realizes the quantum image geometric transforms by means of designing quantum circuits. Eventually, through a combination of the proposals in previous, the encryption and decryption algorithms on quantum gray-scale images is finally accomplished, which could ensure the confidentiality and security of the information in delivery. The algorithms belong to the application of quantum image geometric transformations, for further, the new explorations for quantum image cryptography researches.
NASA Astrophysics Data System (ADS)
Chen, Linfei; Liu, Jingyu; Wen, Jisen; Mao, Haidan; Ge, Fan; Zhao, Daomu
2015-03-01
In this paper, a new method for optical image encryption based on three-beams interference principle and common vector composition is proposed. An original gray image is divided into three parts of amplitude information and three parts of phase information by a common vector composition. We can put the three parts of amplitude information together to form a color image which is regarded as a ciphertext. And the keys of the encryption system are the three phase information. In the decryption process, three beams of coherent light illuminate at the three parts of the ciphertext, pass through the corresponding phase only masks respectively, and finally the decrypted gray image would be obtained at the output plane after Fourier transform and three-beams interference. Computer simulations are presented to verify the possibility of the proposed method.
Status Report on the First Round of the Development of the Advanced Encryption Standard
Nechvatal, James; Barker, Elaine; Dodson, Donna; Dworkin, Morris; Foti, James; Roback, Edward
1999-01-01
In 1997, the National Institute of Standards and Technology (NIST) initiated a process to select a symmetric-key encryption algorithm to be used to protect sensitive (unclassified) Federal information in furtherance of NIST’s statutory responsibilities. In 1998, NIST announced the acceptance of 15 candidate algorithms and requested the assistance of the cryptographic research community in analyzing the candidates. This analysis included an initial examination of the security and efficiency characteristics for each algorithm. NIST has reviewed the results of this research and selected five algorithms (MARS, RC6™, Rijndael, Serpent and Twofish) as finalists. The research results and rationale for the selection of the finalists are documented in this report. The five finalists will be the subject of further study before the selection of one or more of these algorithms for inclusion in the Advanced Encryption Standard.
NASA Astrophysics Data System (ADS)
Karabat, Cagatay; Kiraz, Mehmet Sabir; Erdogan, Hakan; Savas, Erkay
2015-12-01
In this paper, we introduce a new biometric verification and template protection system which we call THRIVE. The system includes novel enrollment and authentication protocols based on threshold homomorphic encryption where a private key is shared between a user and a verifier. In the THRIVE system, only encrypted binary biometric templates are stored in a database and verification is performed via homomorphically randomized templates, thus, original templates are never revealed during authentication. Due to the underlying threshold homomorphic encryption scheme, a malicious database owner cannot perform full decryption on encrypted templates of the users in the database. In addition, security of the THRIVE system is enhanced using a two-factor authentication scheme involving user's private key and biometric data. Using simulation-based techniques, the proposed system is proven secure in the malicious model. The proposed system is suitable for applications where the user does not want to reveal her biometrics to the verifier in plain form, but needs to prove her identity by using biometrics. The system can be used with any biometric modality where a feature extraction method yields a fixed size binary template and a query template is verified when its Hamming distance to the database template is less than a threshold. The overall connection time for the proposed THRIVE system is estimated to be 336 ms on average for 256-bit biometric templates on a desktop PC running with quad core 3.2 GHz CPUs at 10 Mbit/s up/down link connection speed. Consequently, the proposed system can be efficiently used in real-life applications.
P-code enhanced method for processing encrypted GPS signals without knowledge of the encryption code
NASA Technical Reports Server (NTRS)
Meehan, Thomas K. (Inventor); Thomas, Jr., Jess Brooks (Inventor); Young, Lawrence E. (Inventor)
2000-01-01
In the preferred embodiment, an encrypted GPS signal is down-converted from RF to baseband to generate two quadrature components for each RF signal (L1 and L2). Separately and independently for each RF signal and each quadrature component, the four down-converted signals are counter-rotated with a respective model phase, correlated with a respective model P code, and then successively summed and dumped over presum intervals substantially coincident with chips of the respective encryption code. Without knowledge of the encryption-code signs, the effect of encryption-code sign flips is then substantially reduced by selected combinations of the resulting presums between associated quadrature components for each RF signal, separately and independently for the L1 and L2 signals. The resulting combined presums are then summed and dumped over longer intervals and further processed to extract amplitude, phase and delay for each RF signal. Precision of the resulting phase and delay values is approximately four times better than that obtained from straight cross-correlation of L1 and L2. This improved method provides the following options: separate and independent tracking of the L1-Y and L2-Y channels; separate and independent measurement of amplitude, phase and delay L1-Y channel; and removal of the half-cycle ambiguity in L1-Y and L2-Y carrier phase.
48 CFR 352.239-71 - Standard for encryption language.
Code of Federal Regulations, 2011 CFR
2011-10-01
... language. 352.239-71 Section 352.239-71 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES... Standard for encryption language. As prescribed in 339.101(d)(2), the Contracting Officer shall insert the following clause: Standard for Encryption Language (January 2010) (a) The Contractor shall use...
48 CFR 352.239-71 - Standard for encryption language.
Code of Federal Regulations, 2013 CFR
2013-10-01
... language. 352.239-71 Section 352.239-71 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES... Standard for encryption language. As prescribed in 339.101(d)(2), the Contracting Officer shall insert the following clause: Standard for Encryption Language (January 2010) (a) The Contractor shall use...
48 CFR 352.239-71 - Standard for encryption language.
Code of Federal Regulations, 2012 CFR
2012-10-01
... language. 352.239-71 Section 352.239-71 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES... Standard for encryption language. As prescribed in 339.101(d)(2), the Contracting Officer shall insert the following clause: Standard for Encryption Language (January 2010) (a) The Contractor shall use...
48 CFR 352.239-71 - Standard for encryption language.
Code of Federal Regulations, 2014 CFR
2014-10-01
... language. 352.239-71 Section 352.239-71 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES... Standard for encryption language. As prescribed in 339.101(d)(2), the Contracting Officer shall insert the following clause: Standard for Encryption Language (January 2010) (a) The Contractor shall use...
The Escrowed Encryption Standard: The Clipper Chip and Civil Liberties.
ERIC Educational Resources Information Center
Diamond, Ted
1994-01-01
The federal Escrowed Encryption Standard (EES) has been opposed by civil liberties advocates and the computer industry. The author argues that the standard does not threaten privacy as long as its use remains voluntary, alternative forms of encryption are allowed, and the power of government to intercept transmission is kept in check. (20…
Efficient reversible data hiding in encrypted H.264/AVC videos
NASA Astrophysics Data System (ADS)
Xu, Dawen; Wang, Rangding
2014-09-01
Due to the security and privacy-preserving requirements for cloud data management, it is sometimes desired that video content is accessible in an encrypted form. Reversible data hiding in the encrypted domain is an emerging technology, as it can perform data hiding in encrypted videos without decryption, which preserves the confidentiality of the content. Furthermore, the original cover can be losslessly restored after decryption and data extraction. An efficient reversible data hiding scheme for encrypted H.264/AVC videos is proposed. During H.264/AVC encoding, the intraprediction mode, motion vector difference, and the sign bits of the residue coefficients are encrypted using a standard stream cipher. Then, the data-hider who does not know the original video content, may reversibly embed secret data into the encrypted H.264/AVC video by using a modified version of the histogram shifting technique. A scale factor is utilized for selecting the embedding zone, which is scalable for different capacity requirements. With an encrypted video containing hidden data, data extraction can be carried out either in the encrypted or decrypted domain. In addition, real reversibility is realized so that data extraction and video recovery are free of any error. Experimental results demonstrate the feasibility and efficiency of the proposed scheme.
Wang, Xiaogang; Zhao, Daomu
2013-09-01
A nonlinear color and grayscale images cryptosystem based on phase-truncated fractional Fourier transform and optical superposition principle is proposed. In order to realize simultaneous encryption of color and grayscale images, each grayscale image is first converted into two phase masks by using an optical coherent superposition, one of which is treated as a part of input information that will be fractional Fourier transformed while the other in the form of a chaotic random phase mask (CRPM) is used as a decryption key. For the purpose of optical performance, all the processes are performed through three channels, i.e., red, green, and blue. Different from most asymmetric encryption methods, the decryption process is designed to be linear for the sake of effective decryption. The encryption level of a double random phase encryption based on phase-truncated Fourier transform is enhanced by extending it into fractional Fourier domain and the load of the keys management and transmission is lightened by using CRPMs. The security of the proposed cryptosystem is discussed and computer simulation results are presented to verify the validity of the proposed method.
Cryptanalyzing a chaotic encryption algorithm for highly autocorrelated data
NASA Astrophysics Data System (ADS)
Li, Ming; Liu, Shangwang; Niu, Liping; Liu, Hong
2016-12-01
Recently, a chaotic encryption algorithm for highly autocorrelated data was proposed. By adding chaotic diffusion to the former work, the information leakage of the encryption results especially for the images with lower gray scales was eliminated, and both higher-level security and fast encryption time were achieved. In this study, we analyze the security weakness of this scheme. By applying the ciphertext-only attack, the encrypted image can be restored into the substituted image except for the first block; and then, by using the chosen-plaintext attack, the S-boxes, the distribution map, and the block of chaotic map values, can all be revealed, and the encrypted image can be completely cracked. The improvement is also proposed. Experimental results verify our assertion.
Alfalou, A; Brosseau, C; Abdallah, N; Jridi, M
2013-04-08
We introduce a double optimization procedure for spectrally multiplexing multiple images. This technique is adapted from a recently proposed optical setup implementing the discrete cosine transformation (DCT). The new analysis technique is a combination of spectral fusion based on the properties of DCT, specific spectral filtering, and quantization of the remaining encoded frequencies using an optimal number of bits. Spectrally multiplexing multiple images defines a first level of encryption. A second level of encryption based on a real key image is used to reinforce encryption. A set of numerical simulations and a comparison with the well known JPEG (Joint Photographic Experts Group) image compression standard have been carried out to demonstrate the improved performances of this method. The focus here will differ from the method of simultaneous fusion, compression, and encryption of multiple images (SFCE) [Opt. Express 19, 24023 (2011)] in the following ways. Firstly, we shall be concerned with optimizing the compression rate by adapting the size of the spectral block to each target image and decreasing the number of bits required to encode each block. This size adaptation is achieved by means of the root-mean-square (RMS) time-frequency criterion. We found that this size adaptation provides a good tradeoff between bandwidth of spectral plane and number of reconstructed output images. Secondly, the encryption rate is improved by using a real biometric key and randomly changing the rotation angle of each block before spectral fusion. By using a real-valued key image we have been able to increase the compression rate of 50% over the original SFCE method. We provide numerical examples of the effects for size, rotation, and shifting of DCT-blocks which play noteworthy roles in the optimization of the bandwidth of the spectral plane. Inspection of the results for different types of attack demonstrates the robustness of our procedure.
Toussaint, Nigel D; McMahon, Lawrence P; Dowling, Gregory; Holt, Stephen G; Smith, Gillian; Safe, Maria; Knight, Richard; Fair, Kathleen; Linehan, Leanne; Walker, Rowan G; Power, David A
2016-09-28
♦ Background: Increased demand for treatment of end-stage kidney disease has largely been accommodated by a costly increase in satellite hemodialysis (SHD) in most jurisdictions. In the Australian State of Victoria, a marked regional variation in the uptake of home-based dialysis suggests that use of home therapies could be increased as an alternative to SHD. An earlier strategy based solely on increased remuneration had failed to increase uptake of home therapies. Therefore, the public dialysis funder adopted the incidence and prevalence of home-based dialysis therapies as a key performance indicator (KPI) for its health services to encourage greater uptake of home therapies. ♦ Methods: A KPI data collection and bench-marking program was established in 2012 by the Victorian Department of Health and Human Services, with data provided monthly by all renal units in Victoria using a purpose-designed website portal. A KPI Working Group was responsible for analyzing data each quarter and ensuring indicators remained accurate and relevant and each KPI had clear definitions and targets. We present a prospective, observational study of all dialysis patients in Victoria over a 4-year period following the introduction of the renal KPI program, with descriptive analyses to evaluate the proportion of patients using home therapies as well as home dialysis modality survival. ♦ Results: Following the introduction of the KPI program, the net growth of dialysis patient numbers in Victoria remained stable over 4 years, at 75 - 80 per year (approximately 4%). However, unlike the previous decade, about 40% of this growth was through an increase in home dialysis, which was almost exclusively peritoneal dialysis (PD). The increase was identified particularly in the young (20 - 49) and the elderly (> 80). Disappointingly, however, 67% of these incident patients ceased PD within 2 years of commencement, 46% of whom transferred to SHD. ♦ Conclusions: Introduction of a KPI program
A new hyperchaotic circuit with two memristors and its application in image encryption
NASA Astrophysics Data System (ADS)
Wang, Zhulin; Min, Fuhong; Wang, Enrong
2016-09-01
Memristor is a kind of resistance with a memory function and its special properties decide its broad prospect for application. At present, the focus and difficulty of the research in memristor lie in the establishment of new models and related applications. Therefore, in this paper a new continuous and smooth memristor model is put forward first and the correctness of this new model is proved through the study in the phase trajectory relationship between voltage and current. Then based on Chua's circuit, a new fifth-order hyper-chaotic circuit including two new memristor models is designed and the dimensionless mathematical model is deduced. By the classical nonlinear method of circuit analysis, the dissipation of the new system is put into study in this paper. It is proved through numerical simulation, bifurcation diagram, Lyapunov spectrum that the new system has its unique dynamical behavior. At last, chaotic sequence of the new system is used to encrypt the image and the encrypted histogram, the correlation and anti-attack capability between adjacent pixels and the key sensitivity are emphatically analyzed. It turns out that when applied to image encryption, the newly proposed memristor chaotic system has relatively high safety performance.
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Fine-grained Database Field Search Using Attribute-Based Encryption for E-Healthcare Clouds.
Guo, Cheng; Zhuang, Ruhan; Jie, Yingmo; Ren, Yizhi; Wu, Ting; Choo, Kim-Kwang Raymond
2016-11-01
An effectively designed e-healthcare system can significantly enhance the quality of access and experience of healthcare users, including facilitating medical and healthcare providers in ensuring a smooth delivery of services. Ensuring the security of patients' electronic health records (EHRs) in the e-healthcare system is an active research area. EHRs may be outsourced to a third-party, such as a community healthcare cloud service provider for storage due to cost-saving measures. Generally, encrypting the EHRs when they are stored in the system (i.e. data-at-rest) or prior to outsourcing the data is used to ensure data confidentiality. Searchable encryption (SE) scheme is a promising technique that can ensure the protection of private information without compromising on performance. In this paper, we propose a novel framework for controlling access to EHRs stored in semi-trusted cloud servers (e.g. a private cloud or a community cloud). To achieve fine-grained access control for EHRs, we leverage the ciphertext-policy attribute-based encryption (CP-ABE) technique to encrypt tables published by hospitals, including patients' EHRs, and the table is stored in the database with the primary key being the patient's unique identity. Our framework can enable different users with different privileges to search on different database fields. Differ from previous attempts to secure outsourcing of data, we emphasize the control of the searches of the fields within the database. We demonstrate the utility of the scheme by evaluating the scheme using datasets from the University of California, Irvine.
Perceptual security of encrypted images based on wavelet scaling analysis
NASA Astrophysics Data System (ADS)
Vargas-Olmos, C.; Murguía, J. S.; Ramírez-Torres, M. T.; Mejía Carlos, M.; Rosu, H. C.; González-Aguilar, H.
2016-08-01
The scaling behavior of the pixel fluctuations of encrypted images is evaluated by using the detrended fluctuation analysis based on wavelets, a modern technique that has been successfully used recently for a wide range of natural phenomena and technological processes. As encryption algorithms, we use the Advanced Encryption System (AES) in RBT mode and two versions of a cryptosystem based on cellular automata, with the encryption process applied both fully and partially by selecting different bitplanes. In all cases, the results show that the encrypted images in which no understandable information can be visually appreciated and whose pixels look totally random present a persistent scaling behavior with the scaling exponent α close to 0.5, implying no correlation between pixels when the DFA with wavelets is applied. This suggests that the scaling exponents of the encrypted images can be used as a perceptual security criterion in the sense that when their values are close to 0.5 (the white noise value) the encrypted images are more secure also from the perceptual point of view.
NASA Astrophysics Data System (ADS)
Lang, Jun
2015-03-01
In this paper, we propose a novel color image encryption method by using Color Blend (CB) and Chaos Permutation (CP) operations in the reality-preserving multiple-parameter fractional Fourier transform (RPMPFRFT) domain. The original color image is first exchanged and mixed randomly from the standard red-green-blue (RGB) color space to R‧G‧B‧ color space by rotating the color cube with a random angle matrix. Then RPMPFRFT is employed for changing the pixel values of color image, three components of the scrambled RGB color space are converted by RPMPFRFT with three different transform pairs, respectively. Comparing to the complex output transform, the RPMPFRFT transform ensures that the output is real which can save storage space of image and convenient for transmission in practical applications. To further enhance the security of the encryption system, the output of the former steps is scrambled by juxtaposition of sections of the image in the reality-preserving multiple-parameter fractional Fourier domains and the alignment of sections is determined by two coupled chaotic logistic maps. The parameters in the Color Blend, Chaos Permutation and the RPMPFRFT transform are regarded as the key in the encryption algorithm. The proposed color image encryption can also be applied to encrypt three gray images by transforming the gray images into three RGB color components of a specially constructed color image. Numerical simulations are performed to demonstrate that the proposed algorithm is feasible, secure, sensitive to keys and robust to noise attack and data loss.
Zaidan, A A; Zaidan, B B; Kadhem, Z; Larbani, M; Lakulu, M B; Hashim, M
2015-02-01
This paper discusses the possibility of promoting public health and implementing educational health services using Facebook. We discuss the challenges and strengths of using such a platform as a tool for public health care systems from two different perspectives, namely, the view of IT developers and that of physicians. We present a new way of evaluating user interactivity in health care systems from tools provided by Facebook that measure statistical traffic in the Internet. Findings show that Facebook is a very promising tool in promoting e-health services in Web 2.0. Results from statistical traffic show that a Facebook page is more efficient than other pages in promoting public health.
Sang, Jun; Zhao, Jun; Xiang, Zhili; Cai, Bin; Xiang, Hong
2015-08-05
Gyrator transform has been widely used for image encryption recently. For gyrator transform-based image encryption, the rotation angle used in the gyrator transform is one of the secret keys. In this paper, by analyzing the properties of the gyrator transform, an improved particle swarm optimization (PSO) algorithm was proposed to search the rotation angle in a single gyrator transform. Since the gyrator transform is continuous, it is time-consuming to exhaustedly search the rotation angle, even considering the data precision in a computer. Therefore, a computational intelligence-based search may be an alternative choice. Considering the properties of severe local convergence and obvious global fluctuations of the gyrator transform, an improved PSO algorithm was proposed to be suitable for such situations. The experimental results demonstrated that the proposed improved PSO algorithm can significantly improve the efficiency of searching the rotation angle in a single gyrator transform. Since gyrator transform is the foundation of image encryption in gyrator transform domains, the research on the method of searching the rotation angle in a single gyrator transform is useful for further study on the security of such image encryption algorithms.
Multiple Lookup Table-Based AES Encryption Algorithm Implementation
NASA Astrophysics Data System (ADS)
Gong, Jin; Liu, Wenyi; Zhang, Huixin
Anew AES (Advanced Encryption Standard) encryption algorithm implementation was proposed in this paper. It is based on five lookup tables, which are generated from S-box(the substitution table in AES). The obvious advantages are reducing the code-size, improving the implementation efficiency, and helping new learners to understand the AES encryption algorithm and GF(28) multiplication which are necessary to correctly implement AES[1]. This method can be applied on processors with word length 32 or above, FPGA and others. And correspondingly we can implement it by VHDL, Verilog, VB and other languages.
SSEL1.0. Sandia Scalable Encryption Software
Tarman, T.D.
1996-08-29
Sandia Scalable Encryption Library (SSEL) Version 1.0 is a library of functions that implement Sandia`s scalable encryption algorithm. This algorithm is used to encrypt Asynchronous Transfer Mode (ATM) data traffic, and is capable of operating on an arbitrary number of bits at a time (which permits scaling via parallel implementations), while being interoperable with differently scaled versions of this algorithm. The routines in this library implement 8 bit and 32 bit versions of a non-linear mixer which is compatible with Sandia`s hardware-based ATM encryptor.
System for processing an encrypted instruction stream in hardware
Griswold, Richard L.; Nickless, William K.; Conrad, Ryan C.
2016-04-12
A system and method of processing an encrypted instruction stream in hardware is disclosed. Main memory stores the encrypted instruction stream and unencrypted data. A central processing unit (CPU) is operatively coupled to the main memory. A decryptor is operatively coupled to the main memory and located within the CPU. The decryptor decrypts the encrypted instruction stream upon receipt of an instruction fetch signal from a CPU core. Unencrypted data is passed through to the CPU core without decryption upon receipt of a data fetch signal.
Fried, Linda P.; Begg, Melissa D.; Bayer, Ronald
2014-01-01
Public health is at a watershed moment. The world’s health needs are changing, and complex problems require interdisciplinary approaches and systems-based solutions. Our longer lives and changing environments necessitate life-course and structural approaches to prevention. This argues strongly for public health graduate education that adequately prepares trainees to tackle emerging challenges and to lead now and in the future. Nearly a century of scholarship and scientific advances may offer a blueprint for training the next generation of public health leaders. We articulate a case for change; discuss some of the foundational principles that should guide public health education; and discuss what such a change might look like building on prior scholarship, on the examples set by other disciplines, and on our own experience. PMID:24228646
Medical Image Encryption: An Application for Improved Padding Based GGH Encryption Algorithm.
Sokouti, Massoud; Zakerolhosseini, Ali; Sokouti, Babak
2016-01-01
Medical images are regarded as important and sensitive data in the medical informatics systems. For transferring medical images over an insecure network, developing a secure encryption algorithm is necessary. Among the three main properties of security services ( i.e. , confidentiality, integrity, and availability), the confidentiality is the most essential feature for exchanging medical images among physicians. The Goldreich Goldwasser Halevi (GGH) algorithm can be a good choice for encrypting medical images as both the algorithm and sensitive data are represented by numeric matrices. Additionally, the GGH algorithm does not increase the size of the image and hence, its complexity will remain as simple as O(n(2) ). However, one of the disadvantages of using the GGH algorithm is the Chosen Cipher Text attack. In our strategy, this shortcoming of GGH algorithm has been taken in to consideration and has been improved by applying the padding (i.e., snail tour XORing), before the GGH encryption process. For evaluating their performances, three measurement criteria are considered including (i) Number of Pixels Change Rate (NPCR), (ii) Unified Average Changing Intensity (UACI), and (iii) Avalanche effect. The results on three different sizes of images showed that padding GGH approach has improved UACI, NPCR, and Avalanche by almost 100%, 35%, and 45%, respectively, in comparison to the standard GGH algorithm. Also, the outcomes will make the padding GGH resist against the cipher text, the chosen cipher text, and the statistical attacks. Furthermore, increasing the avalanche effect of more than 50% is a promising achievement in comparison to the increased complexities of the proposed method in terms of encryption and decryption processes.
Medical Image Encryption: An Application for Improved Padding Based GGH Encryption Algorithm
Sokouti, Massoud; Zakerolhosseini, Ali; Sokouti, Babak
2016-01-01
Medical images are regarded as important and sensitive data in the medical informatics systems. For transferring medical images over an insecure network, developing a secure encryption algorithm is necessary. Among the three main properties of security services (i.e., confidentiality, integrity, and availability), the confidentiality is the most essential feature for exchanging medical images among physicians. The Goldreich Goldwasser Halevi (GGH) algorithm can be a good choice for encrypting medical images as both the algorithm and sensitive data are represented by numeric matrices. Additionally, the GGH algorithm does not increase the size of the image and hence, its complexity will remain as simple as O(n2). However, one of the disadvantages of using the GGH algorithm is the Chosen Cipher Text attack. In our strategy, this shortcoming of GGH algorithm has been taken in to consideration and has been improved by applying the padding (i.e., snail tour XORing), before the GGH encryption process. For evaluating their performances, three measurement criteria are considered including (i) Number of Pixels Change Rate (NPCR), (ii) Unified Average Changing Intensity (UACI), and (iii) Avalanche effect. The results on three different sizes of images showed that padding GGH approach has improved UACI, NPCR, and Avalanche by almost 100%, 35%, and 45%, respectively, in comparison to the standard GGH algorithm. Also, the outcomes will make the padding GGH resist against the cipher text, the chosen cipher text, and the statistical attacks. Furthermore, increasing the avalanche effect of more than 50% is a promising achievement in comparison to the increased complexities of the proposed method in terms of encryption and decryption processes. PMID:27857824
A layered searchable encryption scheme with functional components independent of encryption methods.
Luo, Guangchun; Peng, Ningduo; Qin, Ke; Chen, Aiguo
2014-01-01
Searchable encryption technique enables the users to securely store and search their documents over the remote semitrusted server, which is especially suitable for protecting sensitive data in the cloud. However, various settings (based on symmetric or asymmetric encryption) and functionalities (ranked keyword query, range query, phrase query, etc.) are often realized by different methods with different searchable structures that are generally not compatible with each other, which limits the scope of application and hinders the functional extensions. We prove that asymmetric searchable structure could be converted to symmetric structure, and functions could be modeled separately apart from the core searchable structure. Based on this observation, we propose a layered searchable encryption (LSE) scheme, which provides compatibility, flexibility, and security for various settings and functionalities. In this scheme, the outputs of the core searchable component based on either symmetric or asymmetric setting are converted to some uniform mappings, which are then transmitted to loosely coupled functional components to further filter the results. In such a way, all functional components could directly support both symmetric and asymmetric settings. Based on LSE, we propose two representative and novel constructions for ranked keyword query (previously only available in symmetric scheme) and range query (previously only available in asymmetric scheme).
A Layered Searchable Encryption Scheme with Functional Components Independent of Encryption Methods
Luo, Guangchun; Qin, Ke
2014-01-01
Searchable encryption technique enables the users to securely store and search their documents over the remote semitrusted server, which is especially suitable for protecting sensitive data in the cloud. However, various settings (based on symmetric or asymmetric encryption) and functionalities (ranked keyword query, range query, phrase query, etc.) are often realized by different methods with different searchable structures that are generally not compatible with each other, which limits the scope of application and hinders the functional extensions. We prove that asymmetric searchable structure could be converted to symmetric structure, and functions could be modeled separately apart from the core searchable structure. Based on this observation, we propose a layered searchable encryption (LSE) scheme, which provides compatibility, flexibility, and security for various settings and functionalities. In this scheme, the outputs of the core searchable component based on either symmetric or asymmetric setting are converted to some uniform mappings, which are then transmitted to loosely coupled functional components to further filter the results. In such a way, all functional components could directly support both symmetric and asymmetric settings. Based on LSE, we propose two representative and novel constructions for ranked keyword query (previously only available in symmetric scheme) and range query (previously only available in asymmetric scheme). PMID:24719565
Information about NCI publications including PDQ cancer information for patients and health professionals, patient-education publications, fact sheets, dictionaries, NCI blogs and newsletters and major reports.
Abuturab, Muhammad Rafiq
2014-10-10
A new optical interference-based multiple-image encryption using spherical wave illumination and gyrator transform is proposed. In this proposal, each secret color image is divided into normalized red, green, and blue component images and independently encoded into corresponding phase-only component images. Then each phase-only component image of all the images are combined together to produce a single-phase-only component image as an input component image, which is bounded with a random phase mask to form a complex image. The two phase-only masks are analytically obtained from the inverse Fourier transformation of the complex image. The host image is chosen as the first phase-only mask, and the complex image hidden in the host image is regarded as the second phase-only mask. The spherical wave is generated to simultaneously illuminate phase-only masks. Then two modulated masks are gyrator transformed. The corresponding transformed images are phase truncated to obtain encrypted images and amplitude truncated to construct decryption keys. The decryption keys, angles of gyrator transform, wavelength and radius of the spherical wave, and individual decryption keys for authorized users are sensitive keys, which enhance the security layers of the system. The proposed system can be implemented by using optoelectronic architecture. Numerical simulation results demonstrate the flexibility of the system.
Biometrics based key management of double random phase encoding scheme using error control codes
NASA Astrophysics Data System (ADS)
Saini, Nirmala; Sinha, Aloka
2013-08-01
In this paper, an optical security system has been proposed in which key of the double random phase encoding technique is linked to the biometrics of the user to make it user specific. The error in recognition due to the biometric variation is corrected by encoding the key using the BCH code. A user specific shuffling key is used to increase the separation between genuine and impostor Hamming distance distribution. This shuffling key is then further secured using the RSA public key encryption to enhance the security of the system. XOR operation is performed between the encoded key and the feature vector obtained from the biometrics. The RSA encoded shuffling key and the data obtained from the XOR operation are stored into a token. The main advantage of the present technique is that the key retrieval is possible only in the simultaneous presence of the token and the biometrics of the user which not only authenticates the presence of the original input but also secures the key of the system. Computational experiments showed the effectiveness of the proposed technique for key retrieval in the decryption process by using the live biometrics of the user.
NASA Astrophysics Data System (ADS)
Wang, Qu; Guo, Qing; Lei, Liang
2013-06-01
We present a novel method for double image encryption that is based on amplitude-phase mixed encoding and multistage random phase encoding in gyrator transform (GT) domains. In the amplitude-phase mixed encoding operation, a random binary distribution matrix is defined to mixed encode two primitive images to a single complex-valued image, which is then encrypted into a stationary white noise distribution by the multistage phase encoding with GTs. Compared with the earlier methods that uses fully phase encoding, the proposed method reduces the difference between two primitive images in key space and sensitivity to the GT orders. The primitive images can be recovered exactly by applying correct keys with initial conditions of chaotic system, the GT orders and the pixel scrambling operation. Numerical simulations demonstrate that the proposed scheme has considerably high security level and certain robustness against data loss and noise disturbance.
Optical image encryption using multilevel Arnold transform and noninterferometric imaging
NASA Astrophysics Data System (ADS)
Chen, Wen; Chen, Xudong
2011-11-01
Information security has attracted much current attention due to the rapid development of modern technologies, such as computer and internet. We propose a novel method for optical image encryption using multilevel Arnold transform and rotatable-phase-mask noninterferometric imaging. An optical image encryption scheme is developed in the gyrator transform domain, and one phase-only mask (i.e., phase grating) is rotated and updated during image encryption. For the decryption, an iterative retrieval algorithm is proposed to extract high-quality plaintexts. Conventional encoding methods (such as digital holography) have been proven vulnerably to the attacks, and the proposed optical encoding scheme can effectively eliminate security deficiency and significantly enhance cryptosystem security. The proposed strategy based on the rotatable phase-only mask can provide a new alternative for data/image encryption in the noninterferometric imaging.
Multiple-image encryption and authentication with sparse representation by space multiplexing.
Gong, Qiong; Liu, Xuyan; Li, Genquan; Qin, Yi
2013-11-01
A multiple-image encryption and authentication approach by space multiplexing has been proposed. The redundant spaces in the previous security systems employing sparse representation strategy are optimized. With the proposal the information of multiple images can be integrated into a synthesized ciphertext that is convenient for storage and transmission. Only when all the keys are correct can the information of the primary images be authenticated. Computer simulation results have demonstrated that the proposed method is feasible and effective. Moreover, the proposal is also proved to be robust against occlusion and noise attacks.
A fingerprint encryption scheme based on irreversible function and secure authentication.
Yang, Yijun; Yu, Jianping; Zhang, Peng; Wang, Shulan
2015-01-01
A fingerprint encryption scheme based on irreversible function has been designed in this paper. Since the fingerprint template includes almost the entire information of users' fingerprints, the personal authentication can be determined only by the fingerprint features. This paper proposes an irreversible transforming function (using the improved SHA1 algorithm) to transform the original minutiae which are extracted from the thinned fingerprint image. Then, Chinese remainder theorem is used to obtain the biokey from the integration of the transformed minutiae and the private key. The result shows that the scheme has better performance on security and efficiency comparing with other irreversible function schemes.
A Fingerprint Encryption Scheme Based on Irreversible Function and Secure Authentication
Yu, Jianping; Zhang, Peng; Wang, Shulan
2015-01-01
A fingerprint encryption scheme based on irreversible function has been designed in this paper. Since the fingerprint template includes almost the entire information of users' fingerprints, the personal authentication can be determined only by the fingerprint features. This paper proposes an irreversible transforming function (using the improved SHA1 algorithm) to transform the original minutiae which are extracted from the thinned fingerprint image. Then, Chinese remainder theorem is used to obtain the biokey from the integration of the transformed minutiae and the private key. The result shows that the scheme has better performance on security and efficiency comparing with other irreversible function schemes. PMID:25873989
Cryptanalysis of an information encryption in phase space
NASA Astrophysics Data System (ADS)
Wang, Y.; Quan, C.; Tay, C. J.
2016-10-01
In this paper, we evaluate the security of an information encryption in phase space. We show that the scheme is vulnerable to two kinds of attack, namely, a chosen-ciphertext attack and a known-plaintext attack which is based on an iterative phase-retrieval algorithm using multiple plaintext-ciphertext pairs. The validity of the proposed methods of attack is verified by numerical simulations. The results cast doubts on the present security of information encryption in phase space.
Shaffer, Audrey; Jun, Cheng Li
2008-07-01
Sir Run Run Shaw Hospital in Hangzhou, China spent five years preparing for a Joint Commission International accreditation survey. In March 2007 it became the first public hospital on the Chinese mainland to attain international accreditation. The Health Information Department, managed according to Western standards, played an integral role in preparing the hospital for the survey.
ERIC Educational Resources Information Center
Clapp, John D.; Hohman, Melinda M.
2002-01-01
Study examined administrators' perceptions of service adequacy, provision of services, and evaluation of services of publicly funded alcohol and other drug treatment systems in California. Administrators reported that systems adequately serve most populations; however some suggested that adolescents, elderly, and homeless were not as adequately…
NASA Astrophysics Data System (ADS)
Lin, Chao; Shen, Xueju; Hua, Binbin; Wang, Zhisong
2015-10-01
We demonstrate the feasibility of three dimensional (3D) polarization multiplexing by optimizing a single vectorial beam using a multiple-signal window multiple-plane (MSW-MP) phase retrieval algorithm. Original messages represented with multiple quick response (QR) codes are first partitioned into a series of subblocks. Then, each subblock is marked with a specific polarization state and randomly distributed in 3D space with both longitudinal and transversal adjustable freedoms. A generalized 3D polarization mapping protocol is established to generate a 3D polarization key. Finally, multiple-QR code is encrypted into one phase only mask and one polarization only mask based on the modified Gerchberg-Saxton (GS) algorithm. We take the polarization mask as the cyphertext and the phase only mask as additional dimension of key. Only when both the phase key and 3D polarization key are correct, original messages can be recovered. We verify our proposal with both simulation and experiment evidences.
Secure data aggregation in wireless sensor networks using homomorphic encryption
NASA Astrophysics Data System (ADS)
Kumar, Manish; Verma, Shekhar; Lata, Kusum
2015-04-01
In a Wireless Sensor Network (WSN), aggregation exploits the correlation between spatially and temporally proximate sensor data to reduce the total data volume to be transmitted to the sink. Mobile agents (MAs) fit into this paradigm, and data can be aggregated and collected by an MA from different sensor nodes using context specific codes. The MA-based data collection suffers due to large size of a typical WSN and is prone to security problems. In this article, homomorphic encryption in a clustered WSN has been proposed for secure and efficient data collection using MAs. The nodes keep encrypted data that are given to an MA for data aggregation tasks. The MA performs all the data aggregation operations upon encrypted data as it migrates between nodes in a tree-like structure in which the nodes are leafs and the cluster head is the root of the tree. It returns and deposits the encrypted aggregated data to the cluster head after traversing through all the intra cluster nodes over a shortest path route. The homomorphic encryption and aggregation processing in encrypted domain makes the data collection process secure. Simulation results confirm the effectiveness of the proposed secure data aggregation mechanism. In addition to security, MA-based mechanism leads to lesser delay and bandwidth requirements.
NASA Astrophysics Data System (ADS)
Zhang, Yushu; Xiao, Di; Wen, Wenying; Tian, Yuan
2013-12-01
In some special multimedia applications, only the regions with semantic information should be provided better protection whereas the other smooth regions can be free of encryption. However, most of the existing multimedia security schemes only consider bits and pixels rather than semantic information during their encryption. Motivated by this, we propose an edge-based lightweight image encryption scheme using chaos-based reversible hidden transform and multiple-order discrete fractional cosine transform. An image is first carried out by the edge detection based on advanced CNN structure with adaptive thresholds to assess data significance in the image. The detection output is a binary image, in which a “1” reflects the detected pixel whereas a “0” is opposite. Both the detected image and the original image are divided into non-overlapping pixel blocks in the same way, respectively. Whether each block is encrypted or not depends on the significance judged by the corresponding detected block. The significant block is performed by reversible hidden transform followed by multiple-order discrete fractional cosine transform parameters and orders of these two transforms are determined by a two dimensional cross chaotic map. Experiment results show the significant contour features of an image that have been largely hidden only by encrypting about half pixels in the average sense. The keys are extremely sensitive and the proposed scheme can resist noise attack to some extent.
A bit-level image encryption algorithm based on spatiotemporal chaotic system and self-adaptive
NASA Astrophysics Data System (ADS)
Teng, Lin; Wang, Xingyuan
2012-09-01
This paper proposes a bit-level image encryption algorithm based on spatiotemporal chaotic system which is self-adaptive. We use a bit-level encryption scheme to reduce the volume of data during encryption and decryption in order to reduce the execution time. We also use the adaptive encryption scheme to make the ciphered image dependent on the plain image to improve performance. Simulation results show that the performance and security of the proposed encryption algorithm can encrypt plaintext effectively and resist various typical attacks.
De Castro, Paola; Marsili, Daniela; Poltronieri, Elisabetta; Calderón, Carlos Agudelo
2012-01-01
Background Open Access (OA) to scientific information is an important step forward in communication patterns, yet we still need to reinforce OA principles to promote a cultural change of traditional publishing practices. The advantages of free access to scientific information are even more evident in public health where knowledge is directly associated with human wellbeing. Objectives An OA ‘consolidation’ initiative in public health is presented to show how the involvement of people and institutions is fundamental to create awareness on OA and promote a cultural change. This initiative is developed within the project NEtwork of COllaboration Between Europe and Latin American Caribbean countries (NECOBELAC), financed by the European Commission. Methods Three actions are envisaged: Capacity building through a flexible and sustainable training programme on scientific writing and OA publishing; creation of training tools based on semantic web technologies; development of a network of supporting institutions. Results In 2010–2011, 23 training initiatives were performed involving 856 participants from 15 countries; topic maps on scientific publication and OA were produced; 195 institutions are included in the network. Conclusions Cultural change in scientific dissemination practices is a long process requiring a flexible approach and strong commitment by all stakeholders. PMID:22630360
Penev, Lyubomir; Hagedorn, Gregor; Mietchen, Daniel; Georgiev, Teodor; Stoev, Pavel; Sautter, Guido; Agosti, Donat; Plank, Andreas; Balke, Michael; Hendrich, Lars; Erwin, Terry
2011-01-01
Abstract Scholarly publishing and citation practices have developed largely in the absence of versioned documents. The digital age requires new practices to combine the old and the new. We describe how the original published source and a versioned wiki page based on it can be reconciled and combined into a single citation reference. We illustrate the citation mechanism by way of practical examples focusing on journal and wiki publishing of taxon treatments. Specifically, we discuss mechanisms for permanent cross-linking between the static original publication and the dynamic, versioned wiki, as well as for automated export of journal content to the wiki, to reduce the workload on authors, for combining the journal and the wiki citation and for integrating it with the attribution of wiki contributors. PMID:21594104
NASA Astrophysics Data System (ADS)
Chai, Xiu-Li; Gan, Zhi-Hua; Lu, Yang; Zhang, Miao-Hui; Chen, Yi-Ran
2016-10-01
Recently, many image encryption algorithms based on chaos have been proposed. Most of the previous algorithms encrypt components R, G, and B of color images independently and neglect the high correlation between them. In the paper, a novel color image encryption algorithm is introduced. The 24 bit planes of components R, G, and B of the color plain image are obtained and recombined into 4 compound bit planes, and this can make the three components affect each other. A four-dimensional (4D) memristive hyperchaotic system generates the pseudorandom key streams and its initial values come from the SHA 256 hash value of the color plain image. The compound bit planes and key streams are confused according to the principles of genetic recombination, then confusion and diffusion as a union are applied to the bit planes, and the color cipher image is obtained. Experimental results and security analyses demonstrate that the proposed algorithm is secure and effective so that it may be adopted for secure communication. Project supported by the National Natural Science Foundation of China (Grant Nos. 61203094 and 61305042), the Natural Science Foundation of the United States (Grant Nos. CNS-1253424 and ECCS-1202225), the Science and Technology Foundation of Henan Province, China (Grant No. 152102210048), the Foundation and Frontier Project of Henan Province, China (Grant No. 162300410196), the Natural Science Foundation of Educational Committee of Henan Province, China (Grant No. 14A413015), and the Research Foundation of Henan University, China (Grant No. xxjc20140006).
Enhanced Usage of Keys Obtained by Physical, Unconditionally Secure Distributions
NASA Astrophysics Data System (ADS)
Kish, Laszlo B.; Granqvist, Claes-Göran
2015-04-01
Unconditionally secure physical key distribution schemes are very slow, and it is practically impossible to use a one-time-pad based cipher to guarantee unconditional security for the encryption of data because using the key bits more than once gives out statistical information, for example via the known-plain-text-attack or by utilizing known components of the protocol and language statistics. Here, we outline a protocol that reduces this speed problem and allows almost-one-time-pad based communication with an unconditionally secure physical key of finite length. The physical, unconditionally secure key is not used for data encryption but is employed in order to generate and share a new software-based key without any known-plain-text component. The software-only-based key distribution is then changed from computationally secure to unconditionally secure, because the communicated key-exchange data (algorithm parameters, one-way functions of random numbers, etc.) are encrypted in an unconditionally secure way with a one-time-pad. For practical applications, this combined physical/software key distribution based communication looks favorable compared to the software-only and physical-only key distribution based communication whenever the speed of the physical key distribution is much lower than that of the software-based key distribution. A mathematical security proof of this new scheme remains an open problem.
Biomolecular optical data storage and data encryption.
Fischer, Thorsten; Neebe, Martin; Juchem, Thorsten; Hampp, Norbert A
2003-03-01
The use of bacteriorhodopsin (BR) as an active layer in write-once-read-many optical storage is presented. This novel feature of BR materials may be used on a wide variety of substrates, among them transparent substrates but also paper and plastics. The physical basis of the recording process is polarization-sensitive two-photon absorption. As an example for this new BR application, an identification card equipped with an optical recording strip is presented, which has a capacity of about 1 MB of data. The recording density currently used is 125 kB/cm2, which is far from the optical limits but allows operation with cheap terminals using plastic optics. In the examples given, data are stored in blocks of 10 kB each. A special optical encryption procedure allows the stored data to be protected from unauthorized reading. The molecular basis of this property is again the polarization-sensitive recording mechanism. The unique combination of optical storage, photochromism, and traceability of the BR material is combined on the single-molecule level. BR introduces a new quality of storage capability for applications with increased security and anticounterfeiting requirements.
A novel chaos-based image encryption algorithm using DNA sequence operations
NASA Astrophysics Data System (ADS)
Chai, Xiuli; Chen, Yiran; Broyde, Lucie
2017-01-01
An image encryption algorithm based on chaotic system and deoxyribonucleic acid (DNA) sequence operations is proposed in this paper. First, the plain image is encoded into a DNA matrix, and then a new wave-based permutation scheme is performed on it. The chaotic sequences produced by 2D Logistic chaotic map are employed for row circular permutation (RCP) and column circular permutation (CCP). Initial values and parameters of the chaotic system are calculated by the SHA 256 hash of the plain image and the given values. Then, a row-by-row image diffusion method at DNA level is applied. A key matrix generated from the chaotic map is used to fuse the confused DNA matrix; also the initial values and system parameters of the chaotic system are renewed by the hamming distance of the plain image. Finally, after decoding the diffused DNA matrix, we obtain the cipher image. The DNA encoding/decoding rules of the plain image and the key matrix are determined by the plain image. Experimental results and security analyses both confirm that the proposed algorithm has not only an excellent encryption result but also resists various typical attacks.
Forensic watermarking and bit-rate conversion of partially encrypted AAC bitstreams
NASA Astrophysics Data System (ADS)
Lemma, Aweke; Katzenbeisser, Stefan; Celik, Mehmet U.; Kirbiz, S.
2008-02-01
Electronic Music Distribution (EMD) is undergoing two fundamental shifts. The delivery over wired broadband networks to personal computers is being replaced by delivery over heterogeneous wired and wireless networks, e.g. 3G and Wi-Fi, to a range of devices such as mobile phones, game consoles and in-car players. Moreover, restrictive DRM models bound to a limited set of devices are being replaced by flexible standards-based DRM schemes and increasingly forensic tracking technologies based on watermarking. Success of these EMD services will partially depend on scalable, low-complexity and bandwidth eficient content protection systems. In this context, we propose a new partial encryption scheme for Advanced Audio Coding (AAC) compressed audio which is particularly suitable for emerging EMD applications. The scheme encrypts only the scale-factor information in the AAC bitstream with an additive one-time-pad. This allows intermediate network nodes to transcode the bitstream to lower data rates without accessing the decryption keys, by increasing the scale-factor values and re-quantizing the corresponding spectral coeficients. Furthermore, the decryption key for each user is customized such that the decryption process imprints the audio with a unique forensic tracking watermark. This constitutes a secure, low-complexity watermark embedding process at the destination node, i.e. the player. As opposed to server-side embedding methods, the proposed scheme lowers the computational burden on servers and allows for network level bandwidth saving measures such as multi-casting and caching.
Combined data encryption and compression using chaos functions
NASA Astrophysics Data System (ADS)
Bose, Ranjan; Pathak, Saumitr
2004-10-01
Past research in the field of cryptography has not given much consideration to arithmetic coding as a feasible encryption technique, with studies proving compression-specific arithmetic coding to be largely unsuitable for encryption. Nevertheless, adaptive modelling, which offers a huge model, variable in structure, and as completely as possible a function of the entire text that has been transmitted since the time the model was initialised, is a suitable candidate for a possible encryption-compression combine. The focus of the work presented in this paper has been to incorporate recent results of chaos theory, proven to be cryptographically secure, into arithmetic coding, to devise a convenient method to make the structure of the model unpredictable and variable in nature, and yet to retain, as far as is possible, statistical harmony, so that compression is possible. A chaos-based adaptive arithmetic coding-encryption technique has been designed, developed and tested and its implementation has been discussed. For typical text files, the proposed encoder gives compression between 67.5% and 70.5%, the zero-order compression suffering by about 6% due to encryption, and is not susceptible to previously carried out attacks on arithmetic coding algorithms.
NASA Astrophysics Data System (ADS)
Usikov, Denis A.
2013-09-01
The 2007 Planetary Defense Conference recommends "to provide or enhance Internet sites to show how threats evolve and to illustrate possible action scenarios". Thereby, establishment of informational and communicational AsteroidAware web-site with the exact, authentic data about the past and the present of Earth's impact events will assist in achievement of positive results and progress in different directions on political, international, social and scientific levels. Expanded ICT's capabilities for popularization of planetary defense can help in resolving the problem of low public interest. The project's primary intent lies in popularizing the concept of planetary defenses and attracting attention to the potential dangers that threaten the Earth from outer space. The result of the efforts falling into the boundaries of this project would be an increased amount of social participation in the process of developing solutions for and increasing awareness of potential collisions between various astral bodies and the Earth. The project is also aimed at creating a foundation for the interaction between scientists and executives from around the world to facilitate international efforts of searching for fitting measures towards lowering threat levels and developing strategies revolving around united actions against potential threats.
Animal welfare: a complex domestic and international public-policy issue--who are the key players?
Bayvel, A C David; Cross, Nicki
2010-01-01
Animal-welfare issues are usually portrayed in the media in a black-and-white fashion, with simple, single-perspective solutions proposed for what are often, in fact, complex policy issues. In this article, we argue that animal welfare is a multifaceted international and domestic public-policy issue that must take account of not only scientific, ethical, and economic issues but also religious, cultural, and international trade policy considerations. Management of animal welfare at a government policy level also requires an approach based on incremental change. Such change must be both science based and ethically principled, and the rate of change must recognize both the expectations of society and the constraints on the animal user. Ideally, such change should involve full ownership and buy-in from the affected animal user group. The range of stakeholders involved in the animal-welfare debate includes industry and producer groups, science bodies, and animal-welfare non-governmental organizations and professional groups, including the veterinary and legal professions. The veterinary profession, in particular, is expected to play an animal-welfare leadership role, and we discuss expectation versus reality at both a national and an international level. This latter discussion includes specific reference to the role of the World Organisation for Animal Health (the OIE) as an intergovernmental organization representing 175 countries and details some of the major achievements since the OIE assumed its international animal-welfare standard-setting role in 2002. We also address the role of the veterinary profession at national, regional, and international levels.
15 CFR Supplement No. 6 to Part 742 - Technical Questionnaire for Encryption Items
Code of Federal Regulations, 2012 CFR
2012-01-01
... 15 Commerce and Foreign Trade 2 2012-01-01 2012-01-01 false Technical Questionnaire for Encryption Items No. Supplement No. 6 to Part 742 Commerce and Foreign Trade Regulations Relating to Commerce and... Questionnaire for Encryption Items (a) For all encryption items: (1) State the name(s) of each product...
2014-01-01
Background Measures to improve the quality and sustainability of healthcare practice and provision have become a policy concern. In addition, the involvement of stakeholders in health policy decision-making has been advocated, as complex questions arise around the structure of funding arrangements in a context of limited resources. Using a case study of assisted reproductive technologies (ART), deliberative engagements with a range of stakeholder groups were held on the topic of how best to structure the distribution of Australian public funding in this domain. Methods Deliberative engagements were carried out with groups of ART consumers, clinicians and community members. The forums were informed by a systematic review of ART treatment safety and effectiveness (focusing, in particular, on maternal age and number of treatment cycles), as well as by international policy comparisons, and ethical and cost analyses. Forum discussions were transcribed and subject to thematic analysis. Results Each forum demonstrated stakeholders’ capacity to understand concepts of choice under resource scarcity and disinvestment, and to countenance options for ART funding not always aligned with their interests. Deliberations in each engagement identified concerns around ‘equity’ and ‘patient responsibility’, culminating in a broad preference for (potential) ART subsidy restrictions to be based upon individual factors rather than maternal age or number of treatment cycles. Community participants were open to restrictions based upon measures of body mass index (BMI) and smoking status, while consumers and clinicians saw support to improve these factors as part of an ART treatment program, as distinct from a funding criterion. All groups advocated continued patient co-payments, with measures in place to provide treatment access to those unable to pay (namely, equity of access). Conclusions Deliberations yielded qualitative, socially-negotiated evidence required to inform ethical
Homomorphic encryption experiments on IBM's cloud quantum computing platform
NASA Astrophysics Data System (ADS)
Huang, He-Liang; Zhao, You-Wei; Li, Tan; Li, Feng-Guang; Du, Yu-Tao; Fu, Xiang-Qun; Zhang, Shuo; Wang, Xiang; Bao, Wan-Su
2017-02-01
Quantum computing has undergone rapid development in recent years. Owing to limitations on scalability, personal quantum computers still seem slightly unrealistic in the near future. The first practical quantum computer for ordinary users is likely to be on the cloud. However, the adoption of cloud computing is possible only if security is ensured. Homomorphic encryption is a cryptographic protocol that allows computation to be performed on encrypted data without decrypting them, so it is well suited to cloud computing. Here, we first applied homomorphic encryption on IBM's cloud quantum computer platform. In our experiments, we successfully implemented a quantum algorithm for linear equations while protecting our privacy. This demonstration opens a feasible path to the next stage of development of cloud quantum information technology.
An Image Encryption Algorithm Based on Information Hiding
NASA Astrophysics Data System (ADS)
Ge, Xin; Lu, Bin; Liu, Fenlin; Gong, Daofu
Aiming at resolving the conflict between security and efficiency in the design of chaotic image encryption algorithms, an image encryption algorithm based on information hiding is proposed based on the “one-time pad” idea. A random parameter is introduced to ensure a different keystream for each encryption, which has the characteristics of “one-time pad”, improving the security of the algorithm rapidly without significant increase in algorithm complexity. The random parameter is embedded into the ciphered image with information hiding technology, which avoids negotiation for its transport and makes the application of the algorithm easier. Algorithm analysis and experiments show that the algorithm is secure against chosen plaintext attack, differential attack and divide-and-conquer attack, and has good statistical properties in ciphered images.
Simultaneous fusion, compression, and encryption of multiple images.
Alfalou, A; Brosseau, C; Abdallah, N; Jridi, M
2011-11-21
We report a new spectral multiple image fusion analysis based on the discrete cosine transform (DCT) and a specific spectral filtering method. In order to decrease the size of the multiplexed file, we suggest a procedure of compression which is based on an adapted spectral quantization. Each frequency is encoded with an optimized number of bits according its importance and its position in the DC domain. This fusion and compression scheme constitutes a first level of encryption. A supplementary level of encryption is realized by making use of biometric information. We consider several implementations of this analysis by experimenting with sequences of gray scale images. To quantify the performance of our method we calculate the MSE (mean squared error) and the PSNR (peak signal to noise ratio). Our results consistently improve performances compared to the well-known JPEG image compression standard and provide a viable solution for simultaneous compression and encryption of multiple images.
Image encryption using random sequence generated from generalized information domain
NASA Astrophysics Data System (ADS)
Xia-Yan, Zhang; Guo-Ji, Zhang; Xuan, Li; Ya-Zhou, Ren; Jie-Hua, Wu
2016-05-01
A novel image encryption method based on the random sequence generated from the generalized information domain and permutation-diffusion architecture is proposed. The random sequence is generated by reconstruction from the generalized information file and discrete trajectory extraction from the data stream. The trajectory address sequence is used to generate a P-box to shuffle the plain image while random sequences are treated as keystreams. A new factor called drift factor is employed to accelerate and enhance the performance of the random sequence generator. An initial value is introduced to make the encryption method an approximately one-time pad. Experimental results show that the random sequences pass the NIST statistical test with a high ratio and extensive analysis demonstrates that the new encryption scheme has superior security.
A System-Level Throughput Model for Quantum Key Distribution
2015-09-17
xv Dictionary QKD = Quantum Key Distribution OTP = One-Time Pad cryptographic algorithm DES = Data Encryption Standard 3DES... quantum transmission, classical transmission, algorithmic complexity and execution, various information theory techniques, and performance of specific...research into quantum computers has posed a threat to security by means of mathematical complexity. In fact, an algorithm has already been written for
The SECOQC quantum key distribution network in Vienna
NASA Astrophysics Data System (ADS)
Peev, M.; Pacher, C.; Alléaume, R.; Barreiro, C.; Bouda, J.; Boxleitner, W.; Debuisschert, T.; Diamanti, E.; Dianati, M.; Dynes, J. F.; Fasel, S.; Fossier, S.; Fürst, M.; Gautier, J.-D.; Gay, O.; Gisin, N.; Grangier, P.; Happe, A.; Hasani, Y.; Hentschel, M.; Hübel, H.; Humer, G.; Länger, T.; Legré, M.; Lieger, R.; Lodewyck, J.; Lorünser, T.; Lütkenhaus, N.; Marhold, A.; Matyus, T.; Maurhart, O.; Monat, L.; Nauerth, S.; Page, J.-B.; Poppe, A.; Querasser, E.; Ribordy, G.; Robyr, S.; Salvail, L.; Sharpe, A. W.; Shields, A. J.; Stucki, D.; Suda, M.; Tamas, C.; Themel, T.; Thew, R. T.; Thoma, Y.; Treiber, A.; Trinkler, P.; Tualle-Brouri, R.; Vannel, F.; Walenta, N.; Weier, H.; Weinfurter, H.; Wimberger, I.; Yuan, Z. L.; Zbinden, H.; Zeilinger, A.
2009-07-01
In this paper, we present the quantum key distribution (QKD) network designed and implemented by the European project SEcure COmmunication based on Quantum Cryptography (SECOQC) (2004-2008), unifying the efforts of 41 research and industrial organizations. The paper summarizes the SECOQC approach to QKD networks with a focus on the trusted repeater paradigm. It discusses the architecture and functionality of the SECOQC trusted repeater prototype, which has been put into operation in Vienna in 2008 and publicly demonstrated in the framework of a SECOQC QKD conference held from October 8 to 10, 2008. The demonstration involved one-time pad encrypted telephone communication, a secure (AES encryption protected) video-conference with all deployed nodes and a number of rerouting experiments, highlighting basic mechanisms of the SECOQC network functionality. The paper gives an overview of the eight point-to-point network links in the prototype and their underlying technology: three plug and play systems by id Quantique, a one way weak pulse system from Toshiba Research in the UK, a coherent one-way system by GAP Optique with the participation of id Quantique and the AIT Austrian Institute of Technology (formerly ARCAustrian Research Centers GmbH—ARC is now operating under the new name AIT Austrian Institute of Technology GmbH following a restructuring initiative.), an entangled photons system by the University of Vienna and the AIT, a continuous-variables system by Centre National de la Recherche Scientifique (CNRS) and THALES Research and Technology with the participation of Université Libre de Bruxelles, and a free space link by the Ludwig Maximillians University in Munich connecting two nodes situated in adjacent buildings (line of sight 80 m). The average link length is between 20 and 30 km, the longest link being 83 km. The paper presents the architecture and functionality of the principal networking agent—the SECOQC node module, which enables the authentic
A Study on the RFID Tag Encryption using Fast SEED
NASA Astrophysics Data System (ADS)
Ko, Hoon; Kim, Jiyeon; Jung, Jongjin; Joe, Susan; Lee, Yongjun; Chang, Yoonseok
2007-12-01
We have to solve the problem of SEED to apply the SEED algorithm in RFID Tag. Because it must keep both a fast performance and low electronic, also it has the limitation of the physical character to it. Although the SEED is more safety than other encryption algorithms, it has a physical trouble when they try to apply it in Tag. Therefore, In this paper we proposed the way to reduce into the 8 rounds, and we implemented the 8 rounded SEED algorithm to RFID tag encryption.
Special encryption considerations for unattended ground sensor systems
NASA Astrophysics Data System (ADS)
Drummond, Allen P.
2004-09-01
Requirements in Unattended Ground Sensor (UGS) systems have grown to include data privacy, message authentication, and anti-spoofing measures. This presents a challenge to the systems architect to consider approaches that defend against known and unknown attacks designed to compromise the system integrity. Encryption has been the preferred method to address these requirements. Encryption may be used to increase our confidence in the data transmitted in sensor networks, but requires greater, not less, attention to system security. After all, in an unencrypted network, at least we "know" that an adversary can read our data.
NASA Astrophysics Data System (ADS)
Hughes, Richard
2004-05-01
Quantum key distribution (QKD) uses single-photon communications to generate the shared, secret random number sequences that are used to encrypt and decrypt secret communications. The unconditional security of QKD is based on the interplay between fundamental principles of quantum physics and information theory. An adversary can neither successfully tap the transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). QKD could be particularly attractive for free-space optical communications, both ground-based and for satellites. I will describe a QKD experiment performed over multi-kilometer line-of-sight paths, which serves as a model for a satellite-to-ground key distribution system. The system uses single-photon polarization states, without active polarization switching, and for the first time implements the complete BB84 QKD protocol including, reconciliation, privacy amplification and the all-important authentication stage. It is capable of continuous operation throughout the day and night, achieving the self-sustaining production of error-free, shared, secret bits. I will also report on the results of satellite-to-ground QKD modeling.
An arbitrated quantum signature protocol based on the chained CNOT operations encryption
NASA Astrophysics Data System (ADS)
Li, Feng-Guang; Shi, Jian-Hong
2015-06-01
At present, the encryption scheme used by most arbitrated quantum signature (AQS) protocols is quantum one-time pad (QOTP) which encrypts data qubit by qubit. Though QOTP can achieve high security for data encryption, it is not suitable for AQS. There are many attacks on AQS using QOTP. In this paper, we propose an AQS protocol based on another encryption scheme called the chained CNOT operations, which encrypts quantum message ensemble. Our protocol preserves all merits in the similar AQS schemes and has better security. Security analysis shows that our protocol cannot be forged and disavowed under the existing attacks.
Public Key Infrastructure (PKI) and Public Key (PK) Enabling
2004-04-01
IA) Implementation," February 6, 2003 (c) DoD Directive 8190.3, " Smart Card Technology," August 31, 2002 (d) DoD Chief Information Officer...with the ASD(NII)/DoD CIO. 5.2.2. Maintain the design of the CAC and provide technical support on matters relating to smart card technology about...on its activities to the Board. DoDI 8520.2, April 1, 2004 ENCLOSURE 2 12 E2.1.7. Common Access Card (CAC). A Department-wide smart card used as
Multiple-image encryption scheme with a single-pixel detector
NASA Astrophysics Data System (ADS)
Yuan, Sheng; Liu, Xuemei; Zhou, Xin; Li, Zhongyang
2016-08-01
A multiple-image encryption (MIE) scheme with a single-pixel detector has been proposed according to the principle of ghost imaging. In this scheme, each of the spatially coherent laser beams is modified by a set of phase-mask keys and illuminates on a secret image. All of the transmitted lights are recorded together by a single-pixel (bucket) detector to obtain a ciphertext, but anyone of the secret images can be decrypted from the ciphertext independently without any mutually overlapped despite some noise in them. The MIE scheme will bring convenience for data storage and transmission, especially in the case that different secret images need to be distributed to different authorized users, because the ciphertext is a real-valued function and this scheme can effectively avoid the secret images being extracted mutually. The basic principle of the MIE scheme is described theoretically and verified by computer simulations. Finally, the feasibility, robustness and encryption capacity are also tested numerically.
Hilton, Shona; Wood, Karen; Patterson, Chris; Katikireddi, Srinivasa Vittal
2014-02-01
On May 24th 2012, Scotland passed the Alcohol (Minimum Pricing) Bill. Minimum unit pricing (MUP) is an intervention that raises the price of the cheapest alcohol to reduce alcohol consumption and related harms. There is a growing literature on industry's influence in policymaking and media representations of policies, but relatively little about frames used by key claim-makers in the public MUP policy debate. This study elucidates the dynamic interplay between key claim-makers to identify lessons for policy advocacy in the media in the UK and internationally. Content analysis was conducted on 262 articles from seven UK and three Scottish national newspapers between 1st May 2011 and 31st May 2012, retrieved from electronic databases. Advocates' and critics' constructions of the alcohol problem and MUP were examined. Advocates depicted the problem as primarily driven by cheap alcohol and marketing, while critics' constructions focused on youth binge drinkers and dependent drinkers. Advocates justified support by citing the intervention's targeted design, but critics denounced the policy as illegal, likely to encourage illicit trade, unsupported by evidence and likely to be ineffective, while harming the responsible majority, low-income consumers and businesses. Critics' arguments were consistent over time, and single statements often encompassed multiple rationales. This study presents advocates with several important lessons for promoting policies in the media. Firstly, it may be useful to shift focus away from young binge drinkers and heavy drinkers, towards population-level over-consumption. Secondly, advocates might focus on presenting the policy as part of a wider package of alcohol policies. Thirdly, emphasis on the success of recent public health policies could help portray the UK and Scotland as world leaders in tackling culturally embedded health and social problems through policy; highlighting past successes when presenting future policies may be a valuable
Hilton, Shona; Wood, Karen; Patterson, Chris; Katikireddi, Srinivasa Vittal
2014-01-01
On May 24th 2012, Scotland passed the Alcohol (Minimum Pricing) Bill. Minimum unit pricing (MUP) is an intervention that raises the price of the cheapest alcohol to reduce alcohol consumption and related harms. There is a growing literature on industry's influence in policymaking and media representations of policies, but relatively little about frames used by key claim-makers in the public MUP policy debate. This study elucidates the dynamic interplay between key claim-makers to identify lessons for policy advocacy in the media in the UK and internationally. Content analysis was conducted on 262 articles from seven UK and three Scottish national newspapers between 1st May 2011 and 31st May 2012, retrieved from electronic databases. Advocates' and critics' constructions of the alcohol problem and MUP were examined. Advocates depicted the problem as primarily driven by cheap alcohol and marketing, while critics' constructions focused on youth binge drinkers and dependent drinkers. Advocates justified support by citing the intervention's targeted design, but critics denounced the policy as illegal, likely to encourage illicit trade, unsupported by evidence and likely to be ineffective, while harming the responsible majority, low-income consumers and businesses. Critics' arguments were consistent over time, and single statements often encompassed multiple rationales. This study presents advocates with several important lessons for promoting policies in the media. Firstly, it may be useful to shift focus away from young binge drinkers and heavy drinkers, towards population-level over-consumption. Secondly, advocates might focus on presenting the policy as part of a wider package of alcohol policies. Thirdly, emphasis on the success of recent public health policies could help portray the UK and Scotland as world leaders in tackling culturally embedded health and social problems through policy; highlighting past successes when presenting future policies may be a valuable
Lithographically Encrypted Inverse Opals for Anti-Counterfeiting Applications.
Heo, Yongjoon; Kang, Hyelim; Lee, Joon-Seok; Oh, You-Kwan; Kim, Shin-Hyun
2016-07-01
Colloidal photonic crystals possess inimitable optical properties of iridescent structural colors and unique spectral shape, which render them useful for security materials. This work reports a novel method to encrypt graphical and spectral codes in polymeric inverse opals to provide advanced security. To accomplish this, this study prepares lithographically featured micropatterns on the top surface of hydrophobic inverse opals, which serve as shadow masks against the surface modification of air cavities to achieve hydrophilicity. The resultant inverse opals allow rapid infiltration of aqueous solution into the hydrophilic cavities while retaining air in the hydrophobic cavities. Therefore, the structural color of inverse opals is regioselectively red-shifted, disclosing the encrypted graphical codes. The decoded inverse opals also deliver unique reflectance spectral codes originated from two distinct regions. The combinatorial code composed of graphical and optical codes is revealed only when the aqueous solution agreed in advance is used for decoding. In addition, the encrypted inverse opals are chemically stable, providing invariant codes with high reproducibility. In addition, high mechanical stability enables the transfer of the films onto any surfaces. This novel encryption technology will provide a new opportunity in a wide range of security applications.
15 CFR Supplement No. 5 to Part 742 - Encryption Registration
Code of Federal Regulations, 2014 CFR
2014-01-01
... producer of encryption or information technology items) (4) Describe whether the products incorporate or... registration, i.e., the information as described in this Supplement, submitted as a support documentation...), 748.1, 748.3 and Supplement No. 2 to part 748 of the EAR. (1) Point of Contact Information (a)...
Query-Biased Preview over Outsourced and Encrypted Data
Luo, Guangchun; Qin, Ke; Chen, Aiguo
2013-01-01
For both convenience and security, more and more users encrypt their sensitive data before outsourcing it to a third party such as cloud storage service. However, searching for the desired documents becomes problematic since it is costly to download and decrypt each possibly needed document to check if it contains the desired content. An informative query-biased preview feature, as applied in modern search engine, could help the users to learn about the content without downloading the entire document. However, when the data are encrypted, securely extracting a keyword-in-context snippet from the data as a preview becomes a challenge. Based on private information retrieval protocol and the core concept of searchable encryption, we propose a single-server and two-round solution to securely obtain a query-biased snippet over the encrypted data from the server. We achieve this novel result by making a document (plaintext) previewable under any cryptosystem and constructing a secure index to support dynamic computation for a best matched snippet when queried by some keywords. For each document, the scheme has O(d) storage complexity and O(log(d/s) + s + d/s) communication complexity, where d is the document size and s is the snippet length. PMID:24078798
Image encryption using the two-dimensional logistic chaotic map
NASA Astrophysics Data System (ADS)
Wu, Yue; Yang, Gelan; Jin, Huixia; Noonan, Joseph P.
2012-01-01
Chaos maps and chaotic systems have been proved to be useful and effective for cryptography. In our study, the two-dimensional logistic map with complicated basin structures and attractors are first used for image encryption. The proposed method adopts the classic framework of the permutation-substitution network in cryptography and thus ensures both confusion and diffusion properties for a secure cipher. The proposed method is able to encrypt an intelligible image into a random-like one from the statistical point of view and the human visual system point of view. Extensive simulation results using test images from the USC-SIPI image database demonstrate the effectiveness and robustness of the proposed method. Security analysis results of using both the conventional and the most recent tests show that the encryption quality of the proposed method reaches or excels the current state-of-the-art methods. Similar encryption ideas can be applied to digital data in other formats (e.g., digital audio and video). We also publish the cipher MATLAB open-source-code under the web page https://sites.google.com/site/tuftsyuewu/source-code.
Primitive Power Roots of Unity and Its Application to Encryption
NASA Astrophysics Data System (ADS)
Hirano, Takato; Wada, Koichiro; Tanaka, Keisuke
We first consider a variant of the Schmidt-Samoa-Takagi encryption scheme without losing additively homomorphic properties. We show that this variant is secure in the sense of IND-CPA under the decisional composite residuosity assumption, and of OW-CPA under the assumption on the hardness of factoring n = p2q. Second, we introduce new algebraic properties “affine” and “pre-image restriction, ” which are closely related to homomorphicity. Intuitively, “affine” is a tuple of functions which have a special homomorphic property, and “pre-image restriction” is a function which can restrict the receiver to having information on the encrypted message. Then, we propose an encryption scheme with primitive power roots of unity in (Z/ns+1)×. We show that our scheme has, in addition to the additively homomorphic property, the above algebraic properties. In addition to the properties, we also show that the encryption scheme is secure in the sense of OW-CPA and IND-CPA under new number theoretic assumptions.
Secure key distribution applications of chaotic lasers
NASA Astrophysics Data System (ADS)
Jiang, Ning; Xue, Chenpeng; Lv, Yunxin; Qiu, Kun
2016-11-01
Chaotic semiconductor laser is a good candidate for secure communication and high-speed true random bit generator, for its characteristics of broad bandwidth and prominent unpredictability. Based on the synchronization property and true random bit generation characteristic of chaotic semiconductor lasers, physical secure key distribution is available. In this work, we majorly show three key distribution schemes stemming from synchronized chaotic semiconductor lasers or chaos-based key exchange protocol. The numerical results demonstrate that the security of the chaos-synchronization-based key distribution scheme can be physically enhanced by adopting dynamic synchronization scheme or encrypted key generation, and that of key distribution with chaos-based key exchange protocol is dependent on the security of the exchange protocol and finally determined by the difficulty of regeneration the chaos system accurately.
Resource Public Key Infrastructure Extension
2012-01-01
Notation IPv4 – Internet Protocol Version Four IPv6 – Internet Protocol Version Six RSA - Rivest, Shamir and Adleman NTP – Network Time Protocol AKI...license the holder or any other person or corporation; or convey any rights or permission to manufacture, use, or sell any patented invention that may...using this RPKI in real-time network operations, software tools that are robust and scalable must be available. Under this and previous Department
All-optical cryptography of M-QAM formats by using two-dimensional spectrally sliced keys.
Abbade, Marcelo L F; Cvijetic, Milorad; Messani, Carlos A; Alves, Cleiton J; Tenenbaum, Stefan
2015-05-10
There has been an increased interest in enhancing the security of optical communications systems and networks. All-optical cryptography methods have been considered as an alternative to electronic data encryption. In this paper we propose and verify the use of a novel all-optical scheme based on cryptographic keys applied on the spectral signal for encryption of the M-QAM modulated data with bit rates of up to 200 gigabits per second.
NASA Astrophysics Data System (ADS)
Sui, Liansheng; Liu, Benqing; Wang, Qiang; Li, Ye; Liang, Junli
2015-12-01
A color image encryption scheme is proposed based on Yang-Gu mixture amplitude-phase retrieval algorithm and two-coupled logistic map in gyrator transform domain. First, the color plaintext image is decomposed into red, green and blue components, which are scrambled individually by three random sequences generated by using the two-dimensional Sine logistic modulation map. Second, each scrambled component is encrypted into a real-valued function with stationary white noise distribution in the iterative amplitude-phase retrieval process in the gyrator transform domain, and then three obtained functions are considered as red, green and blue channels to form the color ciphertext image. Obviously, the ciphertext image is real-valued function and more convenient for storing and transmitting. In the encryption and decryption processes, the chaotic random phase mask generated based on logistic map is employed as the phase key, which means that only the initial values are used as private key and the cryptosystem has high convenience on key management. Meanwhile, the security of the cryptosystem is enhanced greatly because of high sensitivity of the private keys. Simulation results are presented to prove the security and robustness of the proposed scheme.
Fast Video Encryption Using the H.264 Error Propagation Property for Smart Mobile Devices
Chung, Yongwha; Lee, Sungju; Jeon, Taewoong; Park, Daihee
2015-01-01
In transmitting video data securely over Video Sensor Networks (VSNs), since mobile handheld devices have limited resources in terms of processor clock speed and battery size, it is necessary to develop an efficient method to encrypt video data to meet the increasing demand for secure connections. Selective encryption methods can reduce the amount of computation needed while satisfying high-level security requirements. This is achieved by selecting an important part of the video data and encrypting it. In this paper, to ensure format compliance and security, we propose a special encryption method for H.264, which encrypts only the DC/ACs of I-macroblocks and the motion vectors of P-macroblocks. In particular, the proposed new selective encryption method exploits the error propagation property in an H.264 decoder and improves the collective performance by analyzing the tradeoff between the visual security level and the processing speed compared to typical selective encryption methods (i.e., I-frame, P-frame encryption, and combined I-/P-frame encryption). Experimental results show that the proposed method can significantly reduce the encryption workload without any significant degradation of visual security. PMID:25850068
Fast video encryption using the H.264 error propagation property for smart mobile devices.
Chung, Yongwha; Lee, Sungju; Jeon, Taewoong; Park, Daihee
2015-04-02
In transmitting video data securely over Video Sensor Networks (VSNs), since mobile handheld devices have limited resources in terms of processor clock speed and battery size, it is necessary to develop an efficient method to encrypt video data to meet the increasing demand for secure connections. Selective encryption methods can reduce the amount of computation needed while satisfying high-level security requirements. This is achieved by selecting an important part of the video data and encrypting it. In this paper, to ensure format compliance and security, we propose a special encryption method for H.264, which encrypts only the DC/ACs of I-macroblocks and the motion vectors of P-macroblocks. In particular, the proposed new selective encryption method exploits the error propagation property in an H.264 decoder and improves the collective performance by analyzing the tradeoff between the visual security level and the processing speed compared to typical selective encryption methods (i.e., I-frame, P-frame encryption, and combined I-/P-frame encryption). Experimental results show that the proposed method can significantly reduce the encryption workload without any significant degradation of visual security.
Security analysis of an encryption scheme based on nonpositional polynomial notations
NASA Astrophysics Data System (ADS)
Kapalova, Nursulu; Dyusenbayev, Dilmukhanbet
2016-01-01
The aim of the research was to conduct a cryptographic analysis of an encryption scheme developed on the basis of nonpositional polynomial notations to estimate the algorithm strength. Nonpositional polynomial notations (NPNs) are residue number systems (RNSs) based on irreducible polynomials over GF(2). To evaluate if the algorithms developed on the basis of NPNs are secure, mathematical models of cryptanalysis involving algebraic, linear and differential methods have been designed. The cryptanalysis is as follows. A system of nonlinear equations is obtained from a function transforming plaintext into ciphertext with a key. Next, a possibility of transition of the nonlinear system to a linear one is considered. The cryptanalysis was conducted for the cases with known: 1) ciphertext; 2) plaintext and the related ciphertext; 3) plaintext file format; and 4) ASCII-encoded plaintext.
A novel image encryption algorithm using chaos and reversible cellular automata
NASA Astrophysics Data System (ADS)
Wang, Xingyuan; Luan, Dapeng
2013-11-01
In this paper, a novel image encryption scheme is proposed based on reversible cellular automata (RCA) combining chaos. In this algorithm, an intertwining logistic map with complex behavior and periodic boundary reversible cellular automata are used. We split each pixel of image into units of 4 bits, then adopt pseudorandom key stream generated by the intertwining logistic map to permute these units in confusion stage. And in diffusion stage, two-dimensional reversible cellular automata which are discrete dynamical systems are applied to iterate many rounds to achieve diffusion on bit-level, in which we only consider the higher 4 bits in a pixel because the higher 4 bits carry almost the information of an image. Theoretical analysis and experimental results demonstrate the proposed algorithm achieves a high security level and processes good performance against common attacks like differential attack and statistical attack. This algorithm belongs to the class of symmetric systems.
Tulpan, Dan; Regoui, Chaouki; Durand, Guillaume; Belliveau, Luc; Léger, Serge
2013-01-01
This paper presents a novel hybrid DNA encryption (HyDEn) approach that uses randomized assignments of unique error-correcting DNA Hamming code words for single characters in the extended ASCII set. HyDEn relies on custom-built quaternary codes and a private key used in the randomized assignment of code words and the cyclic permutations applied on the encoded message. Along with its ability to detect and correct errors, HyDEn equals or outperforms existing cryptographic methods and represents a promising in silico DNA steganographic approach.
Regoui, Chaouki; Durand, Guillaume; Belliveau, Luc; Léger, Serge
2013-01-01
This paper presents a novel hybrid DNA encryption (HyDEn) approach that uses randomized assignments of unique error-correcting DNA Hamming code words for single characters in the extended ASCII set. HyDEn relies on custom-built quaternary codes and a private key used in the randomized assignment of code words and the cyclic permutations applied on the encoded message. Along with its ability to detect and correct errors, HyDEn equals or outperforms existing cryptographic methods and represents a promising in silico DNA steganographic approach. PMID:23984392
Physical layer one-time-pad data encryption through synchronized semiconductor laser networks
NASA Astrophysics Data System (ADS)
Argyris, Apostolos; Pikasis, Evangelos; Syvridis, Dimitris
2016-02-01
Semiconductor lasers (SL) have been proven to be a key device in the generation of ultrafast true random bit streams. Their potential to emit chaotic signals under conditions with desirable statistics, establish them as a low cost solution to cover various needs, from large volume key generation to real-time encrypted communications. Usually, only undemanding post-processing is needed to convert the acquired analog timeseries to digital sequences that pass all established tests of randomness. A novel architecture that can generate and exploit these true random sequences is through a fiber network in which the nodes are semiconductor lasers that are coupled and synchronized to central hub laser. In this work we show experimentally that laser nodes in such a star network topology can synchronize with each other through complex broadband signals that are the seed to true random bit sequences (TRBS) generated at several Gb/s. The potential for each node to access real-time generated and synchronized with the rest of the nodes random bit streams, through the fiber optic network, allows to implement an one-time-pad encryption protocol that mixes the synchronized true random bit sequence with real data at Gb/s rates. Forward-error correction methods are used to reduce the errors in the TRBS and the final error rate at the data decoding level. An appropriate selection in the sampling methodology and properties, as well as in the physical properties of the chaotic seed signal through which network locks in synchronization, allows an error free performance.
Optical encryption with protection against Dirac delta and plain signal attacks.
Falaggis, Konstantinos; Ramírez Andrade, Ana Hiza; Gaxiola Luna, José Gabriel; Ojeda, Carina Gutierrez; Porras-Aguilar, Rosario
2016-10-15
This Letter proposes an optical encryption technique that disguises the information with modular arithmetic concepts and time-varying noise components that are unknown to the receiver. Optical encryption systems that use these techniques produce a nondeterministic system response, as well as noise like image data that can easily be generated with ordinary spatial light modulators. The principle of this technique is demonstrated for the double random phase encoding (DRPE) method. The conventional DRPE method has major vulnerabilities for Dirac signal and plain signal attacks, making them impractical for secure encryption. It is shown that the proposed encryption technique provides a robustness against these types of attacks, allowing optical DRPE to be employed in secure encryptions. Moreover, applications of this Letter are not limited to DRPE alone but can also be adopted by other optical encryption techniques such as fractional Fourier transform and Fresnel-transform-based techniques.
Novel implementation of memristive systems for data encryption and obfuscation
NASA Astrophysics Data System (ADS)
Du, Nan; Manjunath, Niveditha; Shuai, Yao; Bürger, Danilo; Skorupa, Ilona; Schüffny, René; Mayr, Christian; Basov, Dimitri N.; Di Ventra, Massimiliano; Schmidt, Oliver G.; Schmidt, Heidemarie
2014-03-01
With the rise of big data handling, new solutions are required to drive cryptographic algorithms for maintaining data security. Here, we exploit the nonvolatile, nonlinear resistance change in BiFeO3 memristors [Shuai et al., J. Appl. Phys. 109, 124117 (2011)] by applying a voltage for the generation of second and higher harmonics and develop a new memristor-based encoding system from it to encrypt and obfuscate data. It is found that a BiFeO3 memristor in high and low resistance state can be used to generate two clearly distinguishable sets of second and higher harmonics as recently predicted theoretically [Cohen et al., Appl. Phys. Lett. 100, 133109 (2012)]. The computed autocorrelation of encrypted data using higher harmonics generated by a BiFeO3 memristor shows that the encoded data distribute randomly.
Color image encryption scheme using CML and DNA sequence operations.
Wang, Xing-Yuan; Zhang, Hui-Li; Bao, Xue-Mei
2016-06-01
In this paper, an encryption algorithm for color images using chaotic system and DNA (Deoxyribonucleic acid) sequence operations is proposed. Three components for the color plain image is employed to construct a matrix, then perform confusion operation on the pixels matrix generated by the spatiotemporal chaos system, i.e., CML (coupled map lattice). DNA encoding rules, and decoding rules are introduced in the permutation phase. The extended Hamming distance is proposed to generate new initial values for CML iteration combining color plain image. Permute the rows and columns of the DNA matrix and then get the color cipher image from this matrix. Theoretical analysis and experimental results prove the cryptosystem secure and practical, and it is suitable for encrypting color images of any size.
Data encryption standard ASIC design and development report.
Robertson, Perry J.; Pierson, Lyndon George; Witzke, Edward L.
2003-10-01
This document describes the design, fabrication, and testing of the SNL Data Encryption Standard (DES) ASIC. This device was fabricated in Sandia's Microelectronics Development Laboratory using 0.6 {micro}m CMOS technology. The SNL DES ASIC was modeled using VHDL, then simulated, and synthesized using Synopsys, Inc. software and finally IC layout was performed using Compass Design Automation's CAE tools. IC testing was performed by Sandia's Microelectronic Validation Department using a HP 82000 computer aided test system. The device is a single integrated circuit, pipelined realization of DES encryption and decryption capable of throughputs greater than 6.5 Gb/s. Several enhancements accommodate ATM or IP network operation and performance scaling. This design is the latest step in the evolution of DES modules.
Image encryption using a synchronous permutation-diffusion technique
NASA Astrophysics Data System (ADS)
Enayatifar, Rasul; Abdullah, Abdul Hanan; Isnin, Ismail Fauzi; Altameem, Ayman; Lee, Malrey
2017-03-01
In the past decade, the interest on digital images security has been increased among scientists. A synchronous permutation and diffusion technique is designed in order to protect gray-level image content while sending it through internet. To implement the proposed method, two-dimensional plain-image is converted to one dimension. Afterward, in order to reduce the sending process time, permutation and diffusion steps for any pixel are performed in the same time. The permutation step uses chaotic map and deoxyribonucleic acid (DNA) to permute a pixel, while diffusion employs DNA sequence and DNA operator to encrypt the pixel. Experimental results and extensive security analyses have been conducted to demonstrate the feasibility and validity of this proposed image encryption method.
Using Mathematics to Make Computing on Encrypted Data Secure and Practical
2015-12-01
USING MATHEMATICS TO MAKE COMPUTING ON ENCRYPTED DATA SECURE AND PRACTICAL UNIVERSITY OF CALIFORNIA, IRVINE DECEMBER 2015 FINAL TECHNICAL REPORT...3. DATES COVERED (From - To) DEC 2012 – JUN 2015 4. TITLE AND SUBTITLE USING MATHEMATICS TO MAKE COMPUTING ON ENCRYPTED DATA SECURE AND PRACTICAL...which it is based and the mathematics that can be used to attack it. The security of homomorphic encryption schemes is based on the presumed diculty of
Classification of Encrypted Web Traffic Using Machine Learning Algorithms
2013-06-01
collateral/vpndevc/ps10142/ps11720/ whitepaper c11-704647 ps10164 Products White Paper.html. [3] Akhawe, Devdatta, Bernhard Amann, Matthias Vallentin...Coull, Thomas Ristenpart, and Thomas Shrimpton. Format- Transforming Encryption: More than Meets the DPI, 2012. 73 [24] Eastlake 3rd, D. “Transport...Search”, Oct 18, 2011 2011. [45] Thomas , Brennon D. “Performance Evaluation of a Field Programmable Gate Array-Based System for Detecting and
Encryption and the Loss of Patient Data
ERIC Educational Resources Information Center
Miller, Amalia R.; Tucker, Catherine E.
2011-01-01
Fast-paced IT advances have made it increasingly possible and useful for firms to collect data on their customers on an unprecedented scale. One downside of this is that firms can experience negative publicity and financial damage if their data are breached. This is particularly the case in the medical sector, where we find empirical evidence that…
NASA Astrophysics Data System (ADS)
Zhang, Hong; Hou, Rui; Yi, Lei; Meng, Juan; Pan, Zhisong; Zhou, Yuhuan
2016-07-01
The accurate identification of encrypted data stream helps to regulate illegal data, detect network attacks and protect users' information. In this paper, a novel encrypted data stream identification algorithm is introduced. The proposed method is based on randomness characteristics of encrypted data stream. We use a l1-norm regularized logistic regression to improve sparse representation of randomness features and Fuzzy Gaussian Mixture Model (FGMM) to improve identification accuracy. Experimental results demonstrate that the method can be adopted as an effective technique for encrypted data stream identification.
A novel color image encryption scheme using alternate chaotic mapping structure
NASA Astrophysics Data System (ADS)
Wang, Xingyuan; Zhao, Yuanyuan; Zhang, Huili; Guo, Kang
2016-07-01
This paper proposes an color image encryption algorithm using alternate chaotic mapping structure. Initially, we use the R, G and B components to form a matrix. Then one-dimension logistic and two-dimension logistic mapping is used to generate a chaotic matrix, then iterate two chaotic mappings alternately to permute the matrix. For every iteration, XOR operation is adopted to encrypt plain-image matrix, then make further transformation to diffuse the matrix. At last, the encrypted color image is obtained from the confused matrix. Theoretical analysis and experimental results has proved the cryptosystem is secure and practical, and it is suitable for encrypting color images.
QR code based noise-free optical encryption and decryption of a gray scale image
NASA Astrophysics Data System (ADS)
Jiao, Shuming; Zou, Wenbin; Li, Xia
2017-03-01
In optical encryption systems, speckle noise is one major challenge in obtaining high quality decrypted images. This problem can be addressed by employing a QR code based noise-free scheme. Previous works have been conducted for optically encrypting a few characters or a short expression employing QR codes. This paper proposes a practical scheme for optically encrypting and decrypting a gray-scale image based on QR codes for the first time. The proposed scheme is compatible with common QR code generators and readers. Numerical simulation results reveal the proposed method can encrypt and decrypt an input image correctly.
Interference-based multiple-image encryption with silhouette removal by position multiplexing.
Qin, Yi; Gong, Qiong
2013-06-10
An approach for multiple-image encryption based on interference and position multiplexing is proposed. In the encryption process, multiple images are analytically hidden into three phase-only masks (POMs). The encryption algorithm for this method is quite simple and does not need iterative encoding. For decryption, both the digital method and optical method could be employed. Also, we analyze the multiplexing capacity through the correlation coefficient. In addition, the silhouette problem that exists in previous interference-based encryption methods with two POMs can be eliminated during the generation procedure of POMs based on the interference principle. Simulation results are presented to verify the validity of the proposed approach.
Olama, Mohammed M; Matalgah, Mustafa M; Bobrek, Miljko
2015-01-01
Traditional encryption techniques require packet overhead, produce processing time delay, and suffer from severe quality of service deterioration due to fades and interference in wireless channels. These issues reduce the effective transmission data rate (throughput) considerably in wireless communications, where data rate with limited bandwidth is the main constraint. In this paper, performance evaluation analyses are conducted for an integrated signaling-encryption mechanism that is secure and enables improved throughput and probability of bit-error in wireless channels. This mechanism eliminates the drawbacks stated herein by encrypting only a small portion of an entire transmitted frame, while the rest is not subject to traditional encryption but goes through a signaling process (designed transformation) with the plaintext of the portion selected for encryption. We also propose to incorporate error correction coding solely on the small encrypted portion of the data to drastically improve the overall bit-error rate performance while not noticeably increasing the required bit-rate. We focus on validating the signaling-encryption mechanism utilizing Hamming and convolutional error correction coding by conducting an end-to-end system-level simulation-based study. The average probability of bit-error and throughput of the encryption mechanism are evaluated over standard Gaussian and Rayleigh fading-type channels and compared to the ones of the conventional advanced encryption standard (AES).
Joint image encryption and compression scheme based on IWT and SPIHT
NASA Astrophysics Data System (ADS)
Zhang, Miao; Tong, Xiaojun
2017-03-01
A joint lossless image encryption and compression scheme based on integer wavelet transform (IWT) and set partitioning in hierarchical trees (SPIHT) is proposed to achieve lossless image encryption and compression simultaneously. Making use of the properties of IWT and SPIHT, encryption and compression are combined. Moreover, the proposed secure set partitioning in hierarchical trees (SSPIHT) via the addition of encryption in the SPIHT coding process has no effect on compression performance. A hyper-chaotic system, nonlinear inverse operation, Secure Hash Algorithm-256(SHA-256), and plaintext-based keystream are all used to enhance the security. The test results indicate that the proposed methods have high security and good lossless compression performance.
Experimental QR code optical encryption: noise-free data recovering.
Barrera, John Fredy; Mira-Agudelo, Alejandro; Torroba, Roberto
2014-05-15
We report, to our knowledge for the first time, the experimental implementation of a quick response (QR) code as a "container" in an optical encryption system. A joint transform correlator architecture in an interferometric configuration is chosen as the experimental scheme. As the implementation is not possible in a single step, a multiplexing procedure to encrypt the QR code of the original information is applied. Once the QR code is correctly decrypted, the speckle noise present in the recovered QR code is eliminated by a simple digital procedure. Finally, the original information is retrieved completely free of any kind of degradation after reading the QR code. Additionally, we propose and implement a new protocol in which the reception of the encrypted QR code and its decryption, the digital block processing, and the reading of the decrypted QR code are performed employing only one device (smartphone, tablet, or computer). The overall method probes to produce an outcome far more attractive to make the adoption of the technique a plausible option. Experimental results are presented to demonstrate the practicality of the proposed security system.
Encryption On Grayscale Image For Digital Image Confidentiality Using Shamir Secret Sharing Scheme
NASA Astrophysics Data System (ADS)
Rodiah; Anggraini, Dyah; Fitrianingsih; Kazhimi, Farizan
2016-04-01
The use of high-frequency internet in the process of exchanging information and digital transaction is often accompanied by transmitting digital image in the form of raster images. Secret sharing schemes are multiparty protocols that related to the key establishment which provides protection against any threats of losing cryptography key. The greater the key duplication, the higher the risk of losing the key and vice versa. In this study, Secret Sharing Method was used by employing Shamir Threshold Scheme Algorithm on grayscale digital image with the size of 256×256 pixel obtaining 128×128 pixels of shared image with threshold values (4, 8). The result number of shared images were 8 parts and the recovery process can be carried out by at least using 4 shares of the 8 parts. The result of encryption on grayscale image is capable of producing vague shared image (i.e., no perceptible information), therefore a message in the form of digital image can be kept confidential and secure.
Hughes, Richard John; Thrasher, James Thomas; Nordholt, Jane Elizabeth
2016-11-29
Innovations for quantum key management harness quantum communications to form a cryptography system within a public key infrastructure framework. In example implementations, the quantum key management innovations combine quantum key distribution and a quantum identification protocol with a Merkle signature scheme (using Winternitz one-time digital signatures or other one-time digital signatures, and Merkle hash trees) to constitute a cryptography system. More generally, the quantum key management innovations combine quantum key distribution and a quantum identification protocol with a hash-based signature scheme. This provides a secure way to identify, authenticate, verify, and exchange secret cryptographic keys. Features of the quantum key management innovations further include secure enrollment of users with a registration authority, as well as credential checking and revocation with a certificate authority, where the registration authority and/or certificate authority can be part of the same system as a trusted authority for quantum key distribution.