一种基于身份的可否认认证协议的改进

Enhanced Identity-based Deniable Authentication Protocol

为了满足非交互式的可否认认证协议的安全评估,将密钥泄漏(key-compromise impersonation,KCI)安全属性重新定义为发送方密钥泄漏(sender key-compromise impersonation,SKCI)安全属性,并针对Cao方案存在的发送方密钥泄漏攻击问题,提出一种改进,该方案同原方案相比减少了6次对运算且通信双方的交互次数减少了2次.另外,与同类Liao的改进方案相比,本文方案不需要增加签名机制即可实现身份认证且同时满足可认证性、否认性和发送方密钥泄漏安全性.

To be suitable for the security evaluation of non-interactive deniable authentication protocol,this paper re-defines the attribute of key-compromise impersonation（KCI） as the attribute of sender key-compromise impersonation（SKCI）.A new improved scheme is then proposed for solving the receiver KCI problem of Cao＇s scheme.Compared with the old scheme,the improved scheme saves six times pairing operations and its both sides interactive number of times decreases two times.In addition,the proposed scheme does not need an addition signature,which is necessary in Liao＇s improved scheme,to provide extra authentication and simultaneously satisfies authenticity,deniability and sender key-compromise impersonation security attributes.