Modeling and analysis of an efficient multicast mechanism for UMTS

This paper proposes a multicast mechanism for the universal mobile telecommunication system (UMTS). Our scheme relies on establishing multicast tunnels throughout the network that allow multicast packets to be transferred in an optimal manner on shared links toward multiple destinations. We describe the mechanisms of the scheme in establishing and maintaining the multicast tunnels, managing multicast groups, executing location updates, and performing multicast packet forwarding. As a result of dynamically delivering multicast packets to the downstream nodes that are serving multicast users on a per-packet basis, the multicast mechanism is able to respond well to group dynamics as well as to subscriber mobility. The mechanism also requires little state at intermediate network nodes and can be implemented with only minimal modifications to existing UMTS protocols. Based on a cost analysis in comparison with three related schemes for one-to-many packet delivery, we show that our mechanism performs well under various user distributions.