Performance evaluation of traffic reduction by source port specific multicast router

IP multicast is an effective way of dissemination of the same information to potentially large number of users. In IP multicast, a multicast IP address is used for identifying each multicast session. When large number of various contents should be disseminated, e.g. software distribution to various types of information home appliances, lots of multicast addresses are necessary. Source Port Specific Multicast (SPSM) is an effective way of saving IP multicast addresses. In SPSM, both of a source port of transport layer and an IP address in network layer is used for identification of multicast session. When SPSM routers are partially deployed, Le. SPSM routers and non-SPSM routers (IP multicast router) co-exist in a network, unnecessary traffic may be generated because non-SPSM routers cannot identify multicast sessions having the same multicast address. In this paper, we analyze this unnecessary traffic volume with various deployment scenes of SPSM routers.