Efficient Key Agreement for Large and Dynamic Multicast Groups

Secure multicast represents the core component of many web and multimedia applications such as pay-TV, teleconferencing, real-time distribution of stock market price and etc. The main challenges for secure multicast is scalability, efficiency and authenticity. In this paper, we propose a scalable, efficient, authenticated group key agreement scheme for large and dynamic multicast systems. The proposed key agreement scheme is identity-based which uses the bilinear map over the elliptic curves. Compared with the previously published schemes, our scheme provides group member authenticity without imposing extra mechanism. Furthermore, we give a scalability solution based on the subgroups, which has advantages over the existing schemes. Security analysis shows that our scheme satisfies both forward secrecy and backward secrecy.