A hybrid hyperchaotic based dynamic keystream generator using perturbance process for public key infrastructure application

Abstract

A need for secured communication under hostile condition mandated to incorporate the cryptographic methods in the PKI system. Chaos is another promising paradigm which offshoots from nonlinear dynamics where its randomness has no stochastic origin. Hence a deterministic Pseudo Random Number Generator (PRNG) plays a vital role in chaotic-cryptography. Though many PRNG based chaotic systems are proposed, the low- key space chaotic systems and the finite precision of processor deteriorates the periodic function. The paper intent to achieve larger Lyapunov exponent by the proposed system in the post quantum ecosystem. The proposed system provides an improved key spacing and randomness with a novel approach of perturbing the sequence obtained from the hyperchaotic system with Non-Linear Feedback based Self-Shrinking Generators (NLFSR-SSG). As a result, an improved Lyapunov exponents (2.94, 0.1, 0, −15.341) are obtained and also a dynamic key stream using the proposed hyperchaotic system is generated with high resistance towards cryptanalytic attacks in the post quantum enabled PKI ecosystem.