一种门限代理签名方案的分析与改进  

Analysis and Improvement of a Threshold Proxy Signature Scheme

作　　者：彭娅[1] 

机构地区：[1]广州大学华软软件学院网络技术系,广东广州510990

出　　处：《通信技术》2010年第12期118-120,共3页Communications Technology

摘　　要：C-Y Yang等人提出了一个安全性基于求解离散对数困难性的门限代理签名方案,该方案具有较少的通信量及较高的计算效率。基于数论知识分析该方案存在缺陷:不满足不可伪造性和不可否认性,提出了改进方案将代理密钥以门限的方式在成员间共享,使得每个成员的子代理密钥都包含个体随机数,其他成员无法获知某成员的子代理密钥。改进方案的安全性基于求解离散对数的困难性,能抵御密钥替换攻击,具备不可伪造性和不可否认性。A threshold proxy signature scheme is proposed by S-F Tzeng、M-S Hwang and C-Y Yang,with its security based on the difficulty of solving discrete logarithm.This scheme has seldom communications volume and is of fairly high computing speed.Number theory analysis indicates that this scheme could not satisfy the undeniability and unforgeability.Thus a new scheme is proposed,in which all members hold the sub-key of the proxy key in a threshold way,and each member＇s sub-key involves the individual random number,all members can only know their own sub-key.the new scheme,with its security based on the discrete logarithm problem,could resist various attacks,is of undeniability or unforgeability.

关 键 词：门限代理签名 攻击 离散对数 安全性 

分 类 号：TN918.91[电子电信—通信与信息系统]