Multicast Protocols and Algorithms

Multicast refers to the transmission of data from one sender to an arbitrary set of receivers, a service useful for applications such as group conferencing, media distribution, and update of replicated databases. From an application viewpoint, the importance of multicast is that it allows adressing a set of receivers via a common identifier. From a network viewpoint, the importance of multicast is that when the transmission paths between the sender and the receivers share some links, multicast can conserve resources by only sending the data once over each such link. The most important issues raised by multicast are routing data to multiple destinations with minimal delay and/or duplication, handling feedback from possibly numerous receivers in a scalable manner, and providing appropriate quality-of-service for data delivery to each receiver.