Abstract:

Aiming at the problem of determining the joint quadratic span of multiple sequences proposed by Rizomiliotis, this paper presents an algorithm to calculate the joint quadratic span by using the special block structure of the associated system of linear equations and rearranging the coefficient matrix. The complexity analysis shows that the algorithm can calculate the joint quadratic span of multiple sequences within O(tn2) operations.

Key words: cryptography, stream ciphers, quadratic span, multiple sequences

摘要：

针对Rizomiliotis提出的多序列二次复杂度计算问题(IEEE Transations on Information Theory, 2005, No.5)，利用相应线性方程系统的特殊分块结构，通过重新排列系数矩阵，设计一种求多序列二次复杂度的算法。复杂度分析表明，该算法可以在O(tn2)次运算操作中计算出给定多序列的二次复杂度。

关键词: 密码学, 流密码, 二次复杂度, 多序列

CLC Number: 

• TP309.2