Multicast forwarding table reduction method taking account of redundant traffic volume

摘要

In the Internet, it is one of important issues for multicasting to reduce forwarding table entries which increase linearly with increase of multicast groups. However, since a multicast address is assigned regardless of a geographical distribution of receivers, address aggregation technique using the prefix currently available for unicast traffic, cannot be used. When redundant data packet transmission to some links which are not on a multicast tree is allowed, several multicast groups can be aggregated to one shared one-to-many tree shape. This enables effective reduction of multicast forwarding table entries at a router. However, redundant bandwidth is wasted, of course. In this paper, we propose a new multicast group aggregation technique which takes into account traffic volume of each multicast group. Performance evaluation by computer simulation shows that our proposed scheme can reduce multicast forwarding table entries with small redundant traffic volume.