Abstract: This paper analyzes a group signature scheme that it has the property of member deletion, points out that signature open algorithm and validated algorithm are all invalid, and it has redundant data because of signature parameter setting incorrectly. It improves group signature scheme on the basis of it. By attaching the signature public key to signature parameters, it resolves the problem of the identity revelation algorithm invalidity. By modifying group centre to trusted centre and removing the group manager entity, it resolves the problem of the group centre excessive power to improve the overall effectiveness of improved scheme.

Key words: group signature, signature verification, identity revelation

摘要： 对一个能实现成员删除的群签名方案进行安全分析，指出该方案由于签名参数设置不当，使得签名打开算法和验证算法均无效，并存在冗余数据。在此基础上，改进该群签名方案。改进方案在签名参数里附加签名者公钥，解决签名身份揭示无效的问题；将群中心修改为可信中心，取消群管理员，解决群中心权力过大的问题，从而提高改进方案的整体有效性。

关键词: 群签名, 签名验证, 身份揭示

CLC Number: 

• TP309