Key Management for Secure Multicast Using the RingNet Hierarchy

We propose a novel multicast communications model using a RingNet hierarchy, called the RingNet model, which is a combination of logical trees and logical rings for multicast communications. The RingNet hierarchy consists of four tiers: Border Router Tier (BRT), Access Gateway Tier (AGT), Access Proxy Tier (APT), and Mobile Host Tier (MHT). Within the hierarchy, the upper two tiers are dynamically organized into logical rings with network entities. In this paper, based on the RingNet model, local group concept is proposed. For simple illustration, we choose each AG in AGT as the controller of each local group. Each local group has its own independent local group key. The member's join or leave in a local group only affects the local group, which makes multicast communications potentially scalable to very large groups. In this paper, we propose a novel key management scheme for secure multicast with the RingNet model.