A novel approach to construct S-box based on Rossler system

The substitution box is an essential element in cryptographic algorithms. Indeed, the S-box guarantees the confusion and nonlinearity properties required by secure block ciphers. In this study, we choose the Rossler system to generate a chaotic S-box. Proposed approach is tested for six criteria, which are bijectivity, nonlinearity, strict avalanche criterion (SAC), input/output XOR distribution and linear approximation probability (LP). In order to test the robustness and the suitability of the proposed S-box in real time application, especially in image encryption, we evaluate the statistical analysis of the substituted image such as, correlation, histogram and information entropy. Comparative studies with some selected S-boxes have been performed to prove the effectiveness of the proposed S-box. Experimental results and simulations show that the proposed S-box is powerful against attacks.