A Fast Digital Chaotic Generator for Secure Communication

In this paper, we propose a digitalized chaotic map, Variational Logistic Map (VLM), modified from classical logistic map to be used in secure communication. Compared with classical logistic map, VLM has large parameter space without windows and can be implemented at low hardware cost. Referring to statistical testing suites SP800-22 and TestU01, VLM with the proposed scrambling method can significantly improve the output complexity as compared with other logistic-map based generators and piecewise linear chaotic map. Experiments show that the throughput of a 32-bit VLM is up to 3200 Mbps in 0.18 μm process. Furthermore, a chaotic crypto scheme, Multi-VLM (MVLM), constructed by four 32-bit VLMs can generate an output sequence with a minimal length equal to 2128-1 by a 128-bit external key.