摘要:In 2008, Gang Yao et al. proposed an authenticated 3-round identity-based group key agreement protocol, which is based on Burmester and Desmedt’s protocol proposed at Eurocrypt 94. However, their protocol can only prevent passive attack. If the active attack is allowed, the protocol is vulnerable and an internal attacker can forge her neighbor’s keying material. It is obvious that the protocol do not achieve the aim of authentication. In this paper, we discuss the flaws to attack this protocol and propose an enhanced provably-secure protocol based on their protocol. At last, we make a detailed security analysis of our enhanced authenticated identity-based group key agreement protocol.