流密码输出与输入的关系  

Relations Between Outputs and Inputs of Stream Cipher

作　　者：文飞[1] 

机构地区：[1]广州市农业局信息中心,广东广州510030

出　　处：《信息安全与通信保密》2010年第5期67-68,71,共3页Information Security and Communications Privacy

摘　　要：代数攻击是从方程组的角度来分析流密码加密系统,如何对方程组降次是降低求解复杂度的一个非常重要的方面。如果将寄存器初始状态视为系统的未知输入向量,证明了存在着关于多个输出与输入向量的一个关系,其中,在考虑输出的数目足够大时,输入向量的次数可以达到任意低次。这样就能极大地降低了求解寄存器初始状态的复杂度。Algebraic attack analyzes the stream ciphers from the angle of equations. How to reduce the degree of the equations and solve them is of great signifi cance. If the initial state of the register is regarded as the input variables of the system,that there exists a relation between the variables and the outputs could be verifi ed,and the degree about the variables could be arbitrarily low if the outputs quantity is considered to be large enough. Thus,the complexity of algebraic attack could be greatly reduced.

关 键 词：代数攻击 零化子 代数免疫阶 

分 类 号：TN918.1[电子电信—通信与信息系统]