Application of Genetic Algorithms in the Construction of Invertible Substitution Boxes

Existing literature shows that genetic algorithms can be successfully used for automated construction of S-boxes. In this paper we show the usage of genetic algorithm, more specifically NSGA-II, as an aid in designing and testing of invertible substitution boxes which are special case of substitution boxes. Many cryptographic properties of Sboxes are often contradicting each other. It is therefore difficult to find an optimal solution. NSGA-II proved to be a valuable tool in finding a range of solutions from which we can later select an appropriate S-box for a cipher. We also show that we can use NSGA-II to test integration of S-boxes with a cipher and automatically reject S-boxes which make the cipher weak.