International Journal of Network Security
In this paper, the authors 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.