基于身份聚合签名方案的安全性分析与改进

聚合签名是一种将n个来自不同的签名者对n个不同的消息m的签名聚合成一个单一的签名的数字签名技术。分析了两种签名方案，证明了这两个基于身份聚合签名方案的不安全性。在此基础上，利用双线性技术，提出了改进的基于身份的聚合签名方案。在随机预言模型下，基于Diffie-Hellman问题的计算困难性，证明了提出方案在适应性选择消息和身份攻击下的不可伪造性。

Security analysis and modification of identity-based aggregate signature scheme

An aggregate signature scheme is a digital signature that given n signatures on m distinct messages from n distinct users,it is possible to aggregate all these signatures into a single signature.Two ID-based aggregate signature schemes are analyzed and the insecure is proved.According the given scheme,a new ID-based aggregate signature scheme based on the bilinear pairings is proposed.It is proved that the proposed signature scheme is secure against existential forgery under adaptively chosen message and identity attack in the random oracle model,assuming that the computational Diffie-Hellman problem is hard to solve.