Design of a Novel Pseudo Random Generator based on Walsh Hadamard Transform and Bi S-Boxes

Abstract

A cryptographic technique plays a decisive role in day-to-day life. Usually cryptographic algorithms yield confidentiality and authentication. Several cryptographic applications use random numbers and pseudo random numbers. In this paper, we propose a cryptographically secure pseudo random bit generator (CSPRBG) employing Walsh-Hadamard Transform (WHT) and S-boxes (G S-box and Algebraic S-box). CSPRBG is a major category in pseudo random bit generator (PRBG) and used Blum BlumShub (BBS) Generator for an initial condition. WHT is used in a vast variety of scientific and engineering applications, including bent functions and cryptanalytic optimization techniques in cryptography. S-box is the most crucial source to produce confusion and diffusion in the data and it is based on the algebraic structure of multiplicative cyclic group of the Galois field. The robustness of both the S-boxes inspected in terms of nonlinearity, strict avalanche criterion, bit independence criterion, linear and differential approximation probabilities. The target is to generate a lengthy unpredictable keystream with better performance. The random sequence generated by proposed generator passes the test of National Institute of Standards and Technology (NIST) suite. Meticulous analysishas been performed, in precise, statistical randomness test and random sequences generated from proposed generator can be used for many cryptographic applications specifically as inputs to stream cipher.