随机置换表中闭合状态演化环的特征及其在分组加密中的应用

The Properties of Closed State Evolutive Ring in Random Permutation-Table and its Application to Block Encryption

从Skipjack分组密码的F表出发,对随机置换表中闭合状态演化环的环数出现概率和期望值、闭合状态演化环的平均环长度等进行了研究,得到其封闭的计算式。为快速计算,分别寻找到它们的递推关系式。数值模拟的实验证实了理论结果的正确性。

In this paper the concept of random permutation table is presented from F table in Skipjack block encryption. The probabilities and the expected values of closed state evolutive ring numbers and the average length of state evolutive rings are studied and their closed forms used in computation are given, For quick computation their recurrence forms are obtained. The theoretical results are proved experimentally by numerical simulation.