基于三次线性递归序列密码体制的进一步研究

Further research on public-key cryptosystems based on third-order recurrence sequence

研究了三次线性递归序列的性质,给出了GH密码体制的一种变形,并进一步改进为一种公钥概率加密体制。对所提出加密体制的安全性进行了分析,证明了单向性等价于三次扩环中的部分离散对数问题,语意安全性等价于三次扩环中的判断Diffie-Hellman问题。最后,对加密体制的效率进行了简单的分析,这两个加密体制分别需要传输2logN和4logNbit的数据。

Properties of third-order recurrence sequences were investtgated and a new variant of GH public-key cryptosystem was proposed. It is further improved to be a probabilistic public-key cryptosystem. Then security analysis of the proposed schemes were provided, The one-wayness of the proposed scheme was equivalent to partial discrete logarithm in ring extension and its semantic security was equivalent to decisional Diffie-Hellman problem in ring extension. At last efficiency analysis of the proposed schemes were provided, and these two encryption schemes need to transfer 21ogN and 41ogN- bit respectively.