【摘要】 最近Lee和Chang提出了一种基于离散对数的高效群签名方案。然而,该方案不能抵御伪造攻击,同时不具有不可链接性的特点。敖青云等人提出一种改进的方案,希望能克服Lee-Chang方案的不足。本文首先指出了敖青云等人提出的群签名方案仍然是不安全的,基于Tseng方案,提出了一种改进的群签名方案,并对其安全性进行了简要分析。更多还原

【Abstract】 Recently, Lee and Chang have proposed an efficient group signature scheme based on discrete logarithm problem. However, their scheme can not resist forgery attack and is not unlinkable. Ao Qingyun et al presented an improved scheme to overcome the drawback of Lee and Chang scheme. In this paper, it is pointed out at first that the group signature scheme proposed by Ao Qingyun et al is insecure, and an improved scheme based on Tseng’s scheme has proposed, and a simple security analysis is put forward also. 更多还原