A variant of Baptista's encryption scheme

AbstractThe idea of employing chaotic maps in building encryption schemes has attracted the attention of many researchers since the late 1980s. In 1998, M.S. Baptista proposed an elegant encryption scheme based on a one–dimensional chaotic map. Many variants of this scheme have been proposed. Baptista's scheme and some of its variants have been subjected to cryptanalytic attacks such as the one‐time pad attack and the entropy attack. We propose a variant of Baptista's encryption scheme based on two coupled one–dimensional chaotic maps, which also employs mixing, that is, every character in the ciphertext depends on all preceding plaintext characters. Our proposed scheme overcomes the aforementioned attacks. Empirical results show that this idea improves the performance of the scheme. Baptista's approach generates a ciphertext, which is generally larger than the plaintext, but the distribution of the ciphertext symbols allows compression. Simulation results verify that our proposed scheme accommodates better compression rates than the original scheme. Copyright © 2015 John Wiley & Sons, Ltd.