An Insider Attack Resistant Group Key Agreement Protocol from Pairings

Authenticated group key agreement allows a group of users to generate a shared key which satisfies various security requirements. Several identity-based authenticated group key agreement schemes are proposed. However, these schemes are shown to be vulnerable to insider impersonation attacks that any two malicious group members can impersonate other user to agree some session keys in a new group. In this paper, a simple two round authenticated group agreement scheme based on Burmester and Desmedt´s scheme is proposed. Compared to previous protocols, our protocol is efficient while secure against various known attacks, including key exposure attacks and insider impersonation attacks.