We first design a discrete hyperchaotic system via piece-wise linear state feedback. The states of the closed loop system are locally expanding in two directions but absolutely bounded on the whole, which implies hype...We first design a discrete hyperchaotic system via piece-wise linear state feedback. The states of the closed loop system are locally expanding in two directions but absolutely bounded on the whole, which implies hyperchaos. Then, we use three suchlike hyperchaotic systems with different feedback gain matrices to design a pseudo-random sequence generator (PRSG). Through a threshold function, three sub-sequences generated from the output of piecewise linear functions are changed into 0-1 sequences. Then, followed by XOR operation, an unpredictable pseudo-random sequence (PRS) is ultimately obtained. The analysis and simulation results indicate that the PRS, generated with hyperchaotic systems, has desirable statistical features.展开更多
In chaotic cryptosysterns, using (very) high dimensional chaotic attractors for encrypting a given message maybe can improve the privacy of chaotic encoding. A kind of hyperchaotic systems are studied by using some ...In chaotic cryptosysterns, using (very) high dimensional chaotic attractors for encrypting a given message maybe can improve the privacy of chaotic encoding. A kind of hyperchaotic systems are studied by using some classical methods. The results show that for improving the security of the chaotic cryptosystems, besides the high dimension, the sub-Nyquist sampling interval (SI) is also necessary. Then, we verify this result using the methods of time series analysis.展开更多
A more general form of projective synchronization, so called linear generalized synchronization (LGS) is proposed, which includes the generalized projective synchronization (GPS) and the hybrid projective synchron...A more general form of projective synchronization, so called linear generalized synchronization (LGS) is proposed, which includes the generalized projective synchronization (GPS) and the hybrid projective synchronization (HPS) as its special cases, Based on the adaptive technique and Lyapunov stability theory, a general method for achieving the LGS between two chaotic or hyperehaotic systems with uncertain parameters in any scaling matrix is presented. Some numerical simulations are provided to show the effectiveness and feasibility of the proposed synchronization method.展开更多
Being as unique nonlinear components of block ciphers,substitution boxes(S-boxes) directly affect the security of the cryptographic systems.It is important and difficult to design cryptographically strong S-boxes th...Being as unique nonlinear components of block ciphers,substitution boxes(S-boxes) directly affect the security of the cryptographic systems.It is important and difficult to design cryptographically strong S-boxes that simultaneously meet with multiple cryptographic criteria such as bijection,non-linearity,strict avalanche criterion(SAC),bits independence criterion(BIC),differential probability(DP) and linear probability(LP).To deal with this problem,a chaotic S-box based on the artificial bee colony algorithm(CSABC) is designed.It uses the S-boxes generated by the six-dimensional compound hyperchaotic map as the initial individuals and employs ABC to improve their performance.In addition,it considers the nonlinearity and differential uniformity as the fitness functions.A series of experiments have been conducted to compare multiple cryptographic criteria of this algorithm with other algorithms.Simulation results show that the new algorithm has cryptographically strong S-box while meeting multiple cryptographic criteria.展开更多
基金This project was supported by the National Natural Science Foundation of China (69874025).
文摘We first design a discrete hyperchaotic system via piece-wise linear state feedback. The states of the closed loop system are locally expanding in two directions but absolutely bounded on the whole, which implies hyperchaos. Then, we use three suchlike hyperchaotic systems with different feedback gain matrices to design a pseudo-random sequence generator (PRSG). Through a threshold function, three sub-sequences generated from the output of piecewise linear functions are changed into 0-1 sequences. Then, followed by XOR operation, an unpredictable pseudo-random sequence (PRS) is ultimately obtained. The analysis and simulation results indicate that the PRS, generated with hyperchaotic systems, has desirable statistical features.
基金This project was supported by National"985"Engineering of China .
文摘In chaotic cryptosysterns, using (very) high dimensional chaotic attractors for encrypting a given message maybe can improve the privacy of chaotic encoding. A kind of hyperchaotic systems are studied by using some classical methods. The results show that for improving the security of the chaotic cryptosystems, besides the high dimension, the sub-Nyquist sampling interval (SI) is also necessary. Then, we verify this result using the methods of time series analysis.
基金the National Natural Science Foundation of China (60574045 10661006).
文摘A more general form of projective synchronization, so called linear generalized synchronization (LGS) is proposed, which includes the generalized projective synchronization (GPS) and the hybrid projective synchronization (HPS) as its special cases, Based on the adaptive technique and Lyapunov stability theory, a general method for achieving the LGS between two chaotic or hyperehaotic systems with uncertain parameters in any scaling matrix is presented. Some numerical simulations are provided to show the effectiveness and feasibility of the proposed synchronization method.
基金supported by the National Natural Science Foundation of China(6060309260975042)
文摘Being as unique nonlinear components of block ciphers,substitution boxes(S-boxes) directly affect the security of the cryptographic systems.It is important and difficult to design cryptographically strong S-boxes that simultaneously meet with multiple cryptographic criteria such as bijection,non-linearity,strict avalanche criterion(SAC),bits independence criterion(BIC),differential probability(DP) and linear probability(LP).To deal with this problem,a chaotic S-box based on the artificial bee colony algorithm(CSABC) is designed.It uses the S-boxes generated by the six-dimensional compound hyperchaotic map as the initial individuals and employs ABC to improve their performance.In addition,it considers the nonlinearity and differential uniformity as the fitness functions.A series of experiments have been conducted to compare multiple cryptographic criteria of this algorithm with other algorithms.Simulation results show that the new algorithm has cryptographically strong S-box while meeting multiple cryptographic criteria.