Performance investigations of the IP multicast architecture

The big interest in desktop audio and video conferencing has led to a broad usage of multimedia tools in wide and local area networks. Many of these tools are based upon the IP multicast protocols. The general advantages of multicast services, like the efficient utilization of network resources and thus the possibility to reach arbitrary large numbers of receivers have by now rendered performance considerations of multicast protocols obsolete. Yet, the rapid growth of multicast usage, especially in the IP Internet, may lead to severe congestion problems, if performance trade-offs are not considered carefully in protocol design. In this paper we present performance investigations of the IP multicast architecture with special emphasis on routing protocols. Performance results derived from measurements and simulations will be discussed. Based upon these results, protocol improvements are suggested and evaluated.