一种基于身份无可信中心的认证加密新方案

A New Identity-Based Authenticated Encryption Scheme Without Trusted Center

现有基于身份的认证加密方案普遍需要无条件信任私钥产生中心PKG,恶意PKG能够假冒系统内任何用户收发消息,安全隐患突出。新方案中将PKG生成的私钥信息和用户私有信息共同构成用户私钥,保证用户私钥只为用户所有,结合双线性映射的特征加以验证。新方案保留了PKG作为私钥产生中心在密钥分配管理方面的优势,同时巧妙地消除了PKG作为可信中心存在的安全隐患,解决了可信PKG与无可信认证加密之间的矛盾。分析表明,方案是安全高效的。

In view of existing situation that identity-based authenticated encryption schemes generally needed to trust the PKG(private key generator)unconditionally,then the situation that PGK faked any users within the system to send messages or read the unauthorized messages had become increasingly serious.In this new scheme,user's private key is made from the private key which generated by the PKG and the private infomation which owned to user,eventually achieved user private key privatization.The security is verified by the characteristics of bilinear pairings.The new scheme not only keep advantage of PKG as a private key generator on key distribution management,but also skillfully solve the safety risks problem of PKG as a trusted center,and solve the contradiction between the trusted PKG and untrusted authenticated encryption.Analysis suggests that the proposed scheme is safe and effective.