A Scalable and Distributed Security Protocol for Multicast Communications

In this paper, we propose an efficient and a scalable protocol for secure multicast communication. This protocol is based on the Iolus and the logical key hierarchy protocols. It divides the whole group into several subgroups as in the Iolus protocol. Each subgroup in turn is organized in a logical key hierarchy as in the LKH protocol. This decomposition reduces the complexity for a member join or leave form O(n) to O(logm), where n is the number of the whole group members and m is the number of each subgroup members. The performance of the proposed protocol is compared with that of the Simple App., Iolus and LKH protocols. The comparison is undertaken according to the computational overhead, communication overhead, storage overhead, and message size. The results show that the proposed protocol enhances the group performance in terms of computation overhead, and communication overhead especially at the leave operation.