一种改进的存在特权集的门限群签名方案

摘要

In order to solve the different authority between the signers of group signature, a lot of threshold group signature schemes with privilege sets are proposed.This paper analyzes and studies a threshold group signature scheme which is based on the ElGamal type, and the shortages of this scheme are found which do not satisfy the property of group signature and do not distinguish the single signatures.Aiming at these shortages, an improved threshold group signature scheme with a privilege set based on ECC is proposed.The ability of this scheme to prevent the forgery of KDC and the Clerk is enhanced by adding an authentication key and using an interactive identity verification method under the public environment.The group members prevent the forgery of KDC by using the Pedersen VSS validation methods.The improved scheme can not only achieve the discoveries and revocation of group members, but also have the properties of threshold group signature.%为了解决签名方权限不同的问题,出现了许多存在特权集门限群签名方案.本文通过对一种ElGamal类型存在特权集的门限群签名方案的分析研究,发现该方案不满足群签名特性以及存在单签名不可区分的缺陷.针对上述不足,本文提出了一种基于ECC的存在特权集的门限群签名改进方案.本文方案通过增加成员认证密钥并利用公钥环境下的交互式身份验证方法,有效地防止了密钥分配中心和签名服务者的串通陷害;群成员利用Pedersen VSS验证方法防止密钥分配中心的欺诈.同时方案简单有效地实现了群成员的加入和撤销,具有门限群签名应有的性质.