Chaos-based Block Ciphers: An Overview
Résumé
A variety of chaos-based cryptosystems have been investigated during the last decade. Most of them are based on the structure of Fridrich, which is based on the traditional confusion-diffusion architecture proposed by Shannon. Compared with traditional cryptosystems (DES, 3DES, AES, etc.), the chaos-based cryptosystems are more flexible, more modular and easier to be implemented, which make them more suitable for large scale-data encryption, such as images and videos. The heart of any chaos-based cryptosystem is the chaotic generator and so, a part of the efficiency (robustness, speed) of the system depends greatly on it. In this talk, we give an overview of the state of the art of chaos-based block ciphers and we describe some of our schemes already proposed. Also, we will focus on the essential characteristics of the digital chaotic generator that we published in October 2011 as a French patent and also we published in 2013 an extension of the patent in Europe, China, Japan, and USA. The needed performance of a chaos-based block cipher in terms of security level and speed of calculus depends on the considered application. There is a compromise between the security and the speed of the calculation. The security of these block ciphers will be analyzed.