Towards solving multicast key management problem

An important part of secure multicast is key management. Up to now, no completely satisfying scheme has been proposed, which might explain why secure multicast is not used extensively. In this paper, we discuss some representative solutions to the key management problem and summarize the advantages and disadvantages of them. Then we propose a new scheme, secure transmission backbone (STB), which provides a general solution for both secure multicast and unicast. In our method, a secure transmission backbone is constructed. With such a backbone, it is no longer necessary for each individual multicast group to maintain keys. The key management problem is thus solved/avoided completely. STB avoids using global keys and protects transmissions on each hop using local keys. STB is based on existing routing protocols, and it is highly robust, reliable and cost effective.