Abstract: Contraposed the insecurity of WLC-digital signature scheme, this paper makes some improvement. The main merits are that a valid signature is generated only by the designated clerk participating together: if some new members join the group or some members are deleted left the group, the system parameters and the key pairs of other members remain the same, and that an individual could sign messages for different organizations at the same time with the same secret key pair.

Key words: Digital signature, Threshold signature, Traceability, System stability

摘要： 针对WLC数字签名方案的不安全性，做了一些必要的改进。改进后的方案：只有指定的合成群秘书参与才能生成签名；而当有新成员加入或剔除违规成员时，系统本身的参数及其它成员的密钥对保持不变；系统的成员也可以用唯一的密钥对为不同群的消息签名。

关键词: 数字签名, 门限签名, 可追踪性, 系统稳定性

CLC Number: 

• TP309