Illustrated TCP/IP by Matthew G. Naugle Wiley Computer Publishing, John Wiley & Sons, Inc. ISBN: 0471196568   Pub Date: 11/01/98

Chapter 248
Multicast Components

There are four components to a multicast network: multicast-enabled host NIC, multicast-enabled TCP/IP software, multicast-enabled infrastructure (routers, switches, etc.), and multicast-enabled applications.

Do not confuse the operation of IP multicast as a standalone application. This operates on the very same workstation that you are using today to access IP applications and/or the Internet. IP multicast peacefully coexists with your IP applications.

IP multicast usually does not operate alone; there are other protocols that are used in conjunction with it to provide for VVD (voice, video, and data) over IP. Such protocols are Real Time Protocol (RTP) and the Real Time Control Protocol (RTCP), Real Time Streaming Protocol (RTSP), and Resource Reservation Protocol (RSVP). Similar to this is IP. There are many components to the TCP/IP network and IP is simply one of the components. It provides for datagram delivery. IP multicast is also a component of many. IP multicast is based on a few protocols, but it is all the other necessary components that really make it work.

Berkeley Sockets for Multicast provides an API set that easily enables most Unix hosts to become multicast ready, and Microsoft is supporting multicast in its sockets interface known as WinSock 2.0. With the APIs in place, multicast applications can be built.

Multicast Components