Abstract: Interdomain multicast routing is a challenge, requiring a scalable solution that is suitable for diverse application characteristics. Center-based routing trees overcome some of the limitations associated with traditional shortest-path tree routing, however, they present a new set of routing problems. Specifically, the choice of the center router can be critical in determining the multicast routing performance. We present and assess algorithms to solve two problems: selection of an initial center router, and migration of the center router in response to dynamic chauges in the group membership during the application lifetime. These two problems, and our proposed solutions, may have more general applicability in wide-area networking, e.g., in placing shared resources in the network or estimating bandwidth utilization for multicast distribution.
