Abstract: In order to reduce the damage caused by key exposure in ID-based group signatures, combined with key isolation technology, this paper proposes an ID-based key-insulated group signature scheme. The scheme ensures that even if the temporary private key of current time period is leaking, it will not affect the signature of other time periods. The scheme is based on the CDH difficult problem, and the security can be proved under the random oracle model. Under the same security conditions, the signature length is shorter and the structure is simpler.

Key words: key exposure, ID-based group signature, key-insulated, Computational Diffie-Hellman（CDH）

摘要： 为了减轻在基于身份的群签名中密钥泄露带来的危害，结合密钥隔离技术，提出了基于身份的密钥隔离群签名方案。方案满足即使当前时间段的临时密钥泄露，也不会影响其他时间段的签名。方案基于CDH困难问题，在随机预言模型下可证安全性，且在相同安全条件下，签名长度更短，构造更简单。

关键词: 密钥泄漏, 基于身份的群签名, 密钥隔离, 可计算Diffie-Hellman（CDH）