一种基于中国剩余定理的群签名方案

在群签名方案中,群中任意成员可以代表整个群体生成签名.在有争议的情况下,群管理人可以确定签名人的身份.成员的撤消是群签名中的一个重要问题,在目前已知的各种撤消方案中,还不存在一种方案可以在不改变其它有效群成员的密钥的情况下,安全地撤消群成员.并且增加或撤消一个成员至少都需要指数运算,因此计算复杂度高.本文提出了一种基于中国剩余定理的群签名方案.该方案有三个特征:(1)在不改变其它有效群成员的密钥的情况下,可以安全地增加或撤消群成员;(2)增加或撤消的过程中只需要乘法运算,并且在撤消时群公钥的长度不变;(3)安全性是基于大数分解的困难性.

A Group Signature Scheme Based on Chinese Remainder Theorem

Group signature schemes allow any member of a group to sign message on behalf of the group.In case of dispute,the group manager can reveal the identity of actual signer.Revocation of membership is an important problem in group signature schemes,but among the existing group schemes,there is not any scheme which can safely delete the group member without changing secret keys of the other available group members and the cost of deleting group member is high.A new scheme based on Chinese remainder theorem is proposed in this paper and it has three merits.First,the group manager can safely add or delete members while keeping the secretkeys of the other available members unchanged.Second,only mutiplitation is needed and the length of group center's public keys is unchanged during the revocation.Third,the security of this scheme relies on the factoring of large integers.