Abstract
Due to the increased popularity of group oriented applications and protocols, securing
group communications has become a critical networking issue and has received much attention in
recent years. A secure and efficient group key management protocol is the most fundamental
challenge in group communication security. While key transport protocols may be appropriate for
key establishment in large networks, many collaborative applications require distributed key
agreement protocols. Proposals for key agreement protocols that have been published so far does
not scale for large size group. In this paper we propose a novel framework for scalable key
management protocols in group communication, using both Key Agreement and Key transport
protocols. Our framework is based on a particular clustering of the members of the secure
communicating group into subgroups. We describe a protocol to achieve this clustering scheme.
We describe the architecture and operation of this framework using GDH.2 as a building block.
We show that our framework is scalable to large groups with frequent membership changes.