Research on Cryptosystems and Their Criteria

最近，针对密码系统的攻击事件层出不穷。针对DES或FEAL的差分密码分析和线性密码分析是非常强大的攻击方法。密码攻击的报道在工业组织中有非常严重的影响，因此，我们估计了到目前为止提出的密码攻击的强度，以制造安全的密码系统。我们的研究成果是：(A)估计随机数生成器的强度，并开发估计工具；(B)提出使用个人计算机中事件的随机定时的安全随机数生成器；(C)在快速并行机上对大数进行因式分解，并将其报告给Cunningham Project；(D)估计针对指数型加密算法的定时攻击；(E)提出版权安全代理；以及(F)提出安全密钥分发系统。

Recently, many attacks against cryptosystems have been reported. Differential cryptanalysis and linear cryptanalysis against DES or FEAL are very strong attack methods. The reports of cryptattac have very serious influence among industrial organizations.Hence, we estimated the strength of cryptattacks presented so far, to make secure cryptsystems. Our research results are,(a) estimation of the strength of random number generators, and development of a tool of the estimation,(b) proposal of secure random number generators using random timing of events in personal computers,(c) factorization of large numbers at fast pararell machine, and its report to Cunningham Project,(d) estimation of timing attack against exponential type encryption algorithms,(e) proposal of security agents for copyright, and(f) proposal of secure key distribution systems.