LSR-Based Core Selection in Shared Tree Multicasting

摘要

Multicasting can be done in two different ways: sourcenbased tree approach and shared tree approach. In shared treenapproach, a single shared tree is needed for forwardingnmulticast packets and in source based tree approach,nconstruction of a minimum cost tree per source is needed fornpacket transfer. Hence, shared tree multicasting is preferrednover source based tree approach. Several protocols like CorenBased Tree (CBT), and Protocol Independent MulticastingnSparse Mode (PIM-SM) use shared tree approach. In thisnpaper, we have presented two new concepts named pseudonsub-diameter and super pseudo sub-diameter which have beennused for efficient core selection on networks that use LinknState Routing protocol as the underlying unicast protocol. Innfact, these two concepts are themselves independent ofnwhatever underlying unicast protocol is being used. Thenproposed static core selection method uses pseudo subdiameternconcept and the group based core selection methodnuses super pseudo sub-diameter concept. The presentednmethods select more than one core to achieve fault tolerance.