Abstract: This paper analyzes the existing security of the forward secure ring signature scheme, points out that the scheme exists security omission because of lacking forward security. Aiming at these problems, it proposes an improved forward-security ring signature scheme. The defect that the original scheme is signed with constant is overcome by changing the algorithm of ring signature. The algorithm combines the updating secret key and ring signature. The analysis of security and efficiency shows that the improved scheme has forward security, unconditional anonymity and resisting forging attack, as well as higher signing efficiency.

Key words: forward-security, ring signature, Discrete Logarithm(DL) problem, secret key evolution algorithm

摘要： 对已有前向安全环签名方案进行安全性分析，指出其不具备前向安全性，存在多种安全隐患。为此，提出一种改进的前向安全环签名方案。通过改变环签名算法，将密钥更新和环签名相结合，克服原方案中用常量进行环签名的缺陷。安全性与效率分析表明，改进方案具有前向安全性、无条件匿名性、抗伪造性，且签名效率较高。

关键词: 前向安全, 环签名, 离散对数问题, 密钥更新算法

CLC Number: 

• TP309