Finding an Effective Metric Used for Bijective S-Box Generation by Genetic Algorithms

In cryptography, S-box is a basic component of symmetric key algorithms which performs nonlinear substitution. S-boxes need to be highly nonlinear, so that the cipher can resist linear cryptanalysis. The main criteria for cryptographically strong (n × n) S-box are: • High non linearity; • High algebraic degree; • Balanced structure; • Good auto correlation properties. Our task was to give some suggestions for finding an effective metric used for generation bijective optimal S-Box. Because of the given problem’s complexity, our group considered different approaches and we gave a few suggestions for problem solving