Reconstruction Attack Research Articles

Quantum chaotic image encryption with one time running key

To improve image encryption mechanism and enhance the security of pixel value transformation, a new image encryption scheme is proposed based on quantum chaos. In the phase of key generation, running key related to plaintext is generated by cipher-text successively disturbing chaotic component. In the process of encryption, polynomial multiplication in Galois field is first introduced to perform pixel encryption and then the cipher-text is encrypted again with cipher-text feedback mechanism. The experiment results show that the introduction of disturbing mechanism implements one time running-key stream, minimization of dynamical degradation of digital chaos, and resistance to reconstruction attack. In addition, polynomial multiplication which is first applied in the encryption system degrades the possibility of breaking our scheme in theory. Finally, some analyses such as correlation, sensitivity, min-entropy, and time complexity further demonstrate the security and efficiency of our scheme.

Chaotic Image Encryption Based on Running-Key Related to Plaintext

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.

Outsourcing shortest distance computing with privacy protection

With the advent of cloud computing, it becomes desirable to outsource graphs into cloud servers to efficiently perform complex operations without compromising their sensitive information. In this paper, we take the shortest distance computation as a case to investigate the technique issues in outsourcing graph operations. We first propose a parameter-free, edge-based 2-HOP delegation security model (shorten as 2-HOP delegation model), which can greatly reduce the chances of the structural pattern attack and the graph reconstruction attack. We then transform the original graph into a link graph $$G_l$$ kept locally and a set of outsourced graphs $$\mathcal G _o$$ . Our objectives include (i) ensuring each outsourced graph meeting the requirement of 2-HOP delegation model, (ii) making shortest distance queries be answered using $$G_l$$ and $$\mathcal G _o$$ , (iii) minimizing the space cost of $$G_l$$ . We devise a greedy method to produce $$G_l$$ and $$\mathcal G _o$$ , which can exactly answer shortest distance queries. We also develop an efficient transformation method to support approximate shortest distance answering under a given average additive error bound. The experimental results illustrate the effectiveness and efficiency of our method.

A New Chaotic FH Sequences Generator based On Dynamic Quantization

In this paper a chaotic frequency hopping sequences generator based on dynamic quantification is proposed to address the problem of phase space reconstruction attack. This method is based on twice divisions of dynamic system interval and rotated gear dynamic quantification. Analyzed by computer simulation and statistical methods, the paper compared the performance of the proposed scheme with the existed multi-value quantization chaotic frequency hopping sequences generator. Simulation results show that the proposed method has better multi-address performance than other methods, hence is suitable for the FH-CDMA communication systems.

PESQ-Based Selection of Efficient Partial Encryption Set for Compressed Speech

Adopting an encryption function in voice over Wi-Fi service incurs problems such as additional power consumption and degradation of communication quality. To overcome these problems, a partial encryption (PE) algorithm for compressed speech was recently introduced. However, from the security point of view, the partial encryption sets (PESs) of the conventional PE algorithm still have much room for improvement. This paper proposes a new selection method for finding a smaller PES while maintaining the security level of encrypted speech. The proposed PES selection method employs the perceptual evaluation of the speech quality (PESQ) algorithm to objectively measure the distortion of speech. The proposed method is applied to the ITU-T G.729 speech codec, and content protection capability is verified by a range of tests and a reconstruction attack. The experimental results show that encrypting only 20% of the compressed bitstream is sufficient to effectively hide the entire content of speech.

Estimating parameters of chaotic systems synchronized by external driving signal

Abstract Noise-induced synchronization (NIS) has evoked great research interests recently. Two uncoupled identical chaotic systems can achieve complete synchronization (CS) by feeding a common noise with appropriate intensity. Actually, NIS belongs to the category of external feedback control (EFC). The significance of applying EFC in secure communication lies in fact that the trajectory of chaotic systems is disturbed so strongly by external driving signal that phase space reconstruction attack fails. In this paper, however, we propose an approach that can accurately estimate the parameters of the chaotic systems synchronized by external driving signal through chaotic transmitted signal, driving signal and their derivatives. Numerical simulation indicates that this approach can estimate system parameters and external coupling strength under two driving modes in a very rapid manner, which implies that EFC is not superior to other methods in secure communication.