A METHOD TO CONSTRUCT BIJECTIVE SUBSTITUTION BOX FROM NON-PERMUTATION POWER FUNCTIONS USING HEURISTIC TECHNIQUES

摘要

Bijective substitution box is constructed from non-permutation power functions wherein said non-permutation functions are optimally converted to a permutation function by utilizing the heuristic algorithm of an Optimized Balanced Boolean Function Maker algorithm such that it has high cryptographic properties. The result is a bijective function, which provides desirable cryptographic properties such as high nonlinearity of 108 and high algebraic degree of 7. The said construction of bijective substitution boxes from non-permutation power functions using heuristic techniques comprising steps of first selecting a Boolean map from a plurality of linear power functions and high cryptographic properties power function (102, 104); extending an image of said Boolean map to generate an extended map (106, 108); obtaining a bijective function from said extended image by utilizing Optimized Balanced Boolean Function Maker algorithm (110); and performing analysis on cryptographic properties of substitution box (112). The said steps are iterated until said cryptographic properties meets the predetermined condition of a cryptographically strong bijective substitution box.