The substitution box (S-boxes) is a very important component of block cipher. This paper is devoted to presenting a novel approach for generating dynamically S-boxes using a spatiotemporal chaotic system. Within the algorithm, the key is mapped to system parameters and the hyper-chaotic sequences are generated to construct S-boxes. With different keys, lots of distinct S-boxes can be obtained dynamically. The analytic results indicate that all the criteria such as bijection, nonlinearity, SAC, BIC and differential approximation probability are found to hold in the obtained S-boxes. Furthermore, the S-box's sensitivity to the key is also satisfied well, indicating that the proposed approach can be suitable for designing block cipher with dynamic S-boxes.
['Jun Peng', 'Shangzhu Jin', 'Liang Lei', 'Xiaofeng Liao']
Construction and analysis of dynamic S-boxes based on spatiotemporal chaos