基于分数阶超混沌系统的图像加密算法及安全性分析

对一种基于整数阶超混沌系统的加密算法进行分析,证明其仍无法避免选择明文攻击,提出了一种基于分数阶超混沌系统的加密算法.该分数阶超混沌系统的Lyapunov指数表明,其较以往的整数阶混沌系统具有更复杂的动力学行为.将明文序列间关系参入初值后利用分数阶混沌系统进行迭代,确保系统加密序列与于明文相关联.理论分析和实验结果表明...

Image encryption algorithm and cryptanalysis based on fractal-order hyperchaotic systems

In this paper, the analysis on an improved integer-order hyperchaotic encryption algorithm shows it can not avoid chosen plaintext attack. A further improved fractional-order hyperchaotic encryption algorithm is proposed in this paper. Compared with previous integer-order chaotic systems, a more complex dynamic behavior of the system is indicated by the size of Lyapunov exponent. The relationship is kept in plaintext sequences in the initial values, and then the hyperchaotic systems are iterated to ensure the system encryption sequence associated with the plaintext. The theory analysis and experimental results show the method with the ideal statistics and differential characteristics can resist chosen plaintext attack effectively.