Cryptosystem with one dimensional chaotic maps

Abstract

This paper presents a 64-bits chaotic block cryptosystem, which uses as noise generator one-dimensional chaotic maps with 8 bits sub-blocks data. These chaotic maps use a control parameter that allows them to operate in the chaotic region, which guarantees that each sub-block of data is mixed with unpredictable random noise. Statistical mechanic tools such as: bifurcation diagram, Lyapunov exponent, and invariant distribution have been used to analyze and evaluate the behavior of the noise generator. The cryptosystem has been evaluated using concepts of information theory, such as: entropy, as a diffusion measure in the encryption process, and mutual information as a measure of relationship between plaintext and its respective cryptogram. The noise generator has been used on the non-balanced and dynamic network proposed by L. Kocarev. The randomness of the cryptograms has been evaluated using the NIST random tests. The proposed cryptosystem can be a component in software applications that provides security to stored or communicated information. The proposed cryptosystem has a similar behavior to the one of currently used cryptosystems and it has been designed with chaotic sequence generators, which are aperiodic by definition. © 2011 Springer-Verlag.