Design and analysis of two stream ciphers based on chaotic coupling and multiplexing techniques

In this paper, we design and implement two new stream ciphers based on Pseudo Chaotic Number Generators (PCNGs) which integrate discrete chaotic maps, namely, Piecewise Linear Chaotic Map (PWLCM), Skewtent and Logistic map. They are weakly coupled by a predefined matrix A for the first PCNG and they are coupled by a binary diffusion matrix D for the second one. Each PCNG includes a chaotic multiplexing technique that allows the enhancement of the robustness of the system. The structure is implemented with finite precision N = 32 bits in C language. Security performance of the proposed stream ciphers is analysed and several cryptanalytic and statistical tests are applied. Experimental results highlight robustness as well as efficiency in terms of computation time of these two stream ciphers.