Abstract: Aiming at the requirement that an stream cipher should have a good self-correlation, this paper proposes the concept of multinomial relation bias. Through access to the linear terms of key stream, by using Gauss elimination method, 9 multinomial relation polynomials of Trivium are found and the max bias can reach to , which is obtained by probability test. The difficulty of distinguishing attack on Trivium is illustrated.

Key words: stream cipher, Trivium, self-correlation, multinomial relation bias

摘要： 针对流密码序列应具有良好自相关性的要求，提出流密码序列多项相关偏差的概念，通过获取输出密钥流的线性项，利用高斯消元的方法，找到Trivium算法的9个相关多项式，通过概率测试获得的Trivium算法最大相关偏差值达 ，并利用最大相关偏差说明对Trivium算法进行区分攻击比较困难。

关键词: 流密码, Trivium算法, 自相关性, 多项相关偏差

CLC Number: 

• TP301.6