An Efficient Routing Algorithm for Overlay Multicast in Diffserv Domains

Abstract

We propose a novel approach to enable QoS-guaranteed overlay multicast among Diffserv domains. Our approach exploits the edge routers as the overlay nodes while complying with the core-stateless principle of the Diffserv architecture. The contribution of our work is two-fold. First, we devise a distributed insertion and relocation algorithm (DIRA) to organize the edge routers of the same domain into an efficient overlay multicast tree. The algorithm keeps a candidate parent for each node so that as the incremental tree building process is going on, the tree topology can be adjusted timely for a small cost according to its dynamic membership. Due to its distributed nature, the algorithm imposes no huge computation burden on any single node. Second, our approach combine the overlay multicast technique with the QoS architecture seamlessly, which provides a promising platform for various applications. Through a large amount of simulations, we prove that DIRA is more competitive than other IP multicast and overlay multicast schemes in terms of tree cost and other metrics.