A new design of dynamic S-Box based on two chaotic maps

The use of chaotic maps to construct dynamic S-Box has been increasingly studied. The aim of this paper is to propose a new design of dynamic chaotic S-Box that enhances the security criteria of the block ciphers. In fact, our S-Box is based on the combination of two chaotic maps: one and three dimensional piecewise linear maps. The randomness of these maps was verified by using the NIST test package. However, the conversion method seems to be crucial to keep the randomness and the uniformity of the binary sequences. The security analysis shows that the dynamic S-Boxes based on two chaotic maps have the lowest linear approximation probability (L_p= 0.0625), the closest value to 0.5 of the strict avalanche criteria (SAC=0.4998) and also an equiprobable input/output distribution (DF=10/256).