Abstract: A more security analysis on the ID-based Authenticated Group Key Agreement(ID-AGKA) is given and it is found that the ID-based AGKA does not resist outsider attack, that is, an adversary can make a group session key inconsistent, which can not be detected by the users in the group however. An improvement of the AGKA scheme is proposed. Security analysis shows the scheme can resist outside attack.

Key words: authentication, group key agreement protocol, outside attack

摘要： 指出用Pairings实现的基于身份的具有常数轮可扩展的认证群密钥协商协议ID-AGKA不能抵抗外部攻击，即攻击者A能使群中用户在运行完该协议后所产生的会话密钥不一致，且不会被群中成员发现。针对该安全缺陷，给出改进方案，并对其安全性进行分析，改进方案在原方案安全性的基础上能抵挡外部攻击。

关键词: 认证, 群密钥协商协议, 外部攻击

CLC Number: 

• TP309