Ateniese等人提出的不可关联秘密握手方案(NDSS’07)在不同组织共享一对群密钥时不能严格地划分不同组织,在实用性方面存在不足。为此,提出一个新型不可关联秘密握手方案USH,使用消息恢复签名技术,基于抗击七个叛徒勾结攻击的困难问题,实现抵抗恶意群管理中心攻击的强不可关联性。理论分析结果表明,与原方案相比,USH可以提供明确的组织划分,实现更简单,存储和计算开销更少。
The unlinkable secret handshake scheme proposed by Ateniese et al can not strictly distinguish different groups and thus its practicality is limited. This paper proposes a new unlinkable secret handshake scheme named USH(Unlinkable Secret Handshakes) by using the variant of message recovery signature. Based on the difficulty problem of collusion attack algorithm with k traitors, it achieves the strong unlinkability against group authority with reusable credentials. Compared with the previous schemes, USH provides the definite group division and more simple construction which also takes advantage on storage and computation Costs.