A Stream Cipher Based on Fractional Pseudo Chaotic Random Number Generator

In this paper, we focus on the design of fractional pseudo-chaotic random number generator (FPCRNG) based on the coupling of fractional chaotic systems. The proposed FPCRNG is composed of 3 fractional chaotic systems, including one fractional generalized double-humped logistic system, two 3D fractional systems Chen's system and Lu's system, and one classical skew-tent map. A non-uniform grid calculation method is employed by introducing the skew-tent map into the numerical calculation of the states of the Chen's system and Lu's system to obtain greater chaoticity in terms of Lyapunov exponent. The XOR (exclusive-or) operations are applied to the fractional systems to obtain the final pseudo-chaotic outputs. The security analysis and statistical experiment of a stream cipher implementing the FPCRNG prove that the proposed structure is effective and can be used in the cryptosystem.