An Efficient Authenticated Group Key Agreement Protocol

Authenticated group key agreement is an important cryptographic mechanism underlying many collaborative and distributed applications. Some identity-based authenticated group key agreement schemes are proposed, however most of these protocols are vulnerable to insider attacks, while the other protocols are not efficient in communication. In this paper a new authenticated group key agreement protocol is proposed based on a modified identity-based cryptography infrastructure with new system setup and key extraction algorithms. The main feature of this protocol is that it needs only one round, which is optimal in terms of communication complexity; meanwhile the protocol is secure against insider attacks such as impersonation attacks and other known attacks.