关键词: 信息安全, 密码学, 布尔函数, 粒子群

Abstract: Cryptography is very important in the information security area.Many problems in the cryptology can be represented as optimizationproblems in mathematics.This paper applies Particle Swarm Optimization(PSO) algorithm in the cryptology area to design Boolean function in cryptography.According to the original thought of the PSO algorithm，this paper imports swap operator and swap sequence concept，designs the PSO algorithm which can search directly on the discrete domain.By the improved method，it is easy to automatically design Boolean function which satisfies hign non-linearity and low autocorrelation to construct more securely cipher.Compared with the general mathematic construction method，this method has the superiority in automatic design and more effectively.

Key words: information security, cryptography, Boolean function, Particle Swarm Optimization(PSO)