May 2004. "Session Initiation Protocol", www.cs.columbia.edu/sip/, Jan 30 2005 "Session Initiation Protocol (sip)" www.ietf.org/html.charters/sip-charter.htm Jan 18,2005. This Page Intentionally Left Blank STANDARDS FOR CONFERENCING OVER IP NETWORKS The standards that have come out of the IETF have been impressive. They are produced quickly, and they work. Carl Malamud THE INTERNET AND INTERACTIVE MULTIMEDIA Today's enterprise seeks out networks capable of transmitting all media-voice, still-image moving-image, and data. The goal is to find a single solution for all corporate information flows, to front-end it with a Web browser, and endow it with enough bandwidth SO that the average corporate user never has to give the network a second thought. With the rise in popularity of the Internet and its enterprise-adapted equivalent, the intranet, the direction of the enterprise network is now clear. Corporate America is migrating to TCP/IP (Transmission Control Protocol/Internet Protocol) and abandoning proprietary networking protocols. While open-systems standards are great, it is also true that they evolve in response to a particular need or application set. This holds true for TCP/IP, a set of Internet Engineering Task Force (IETF) protocols that are defined in a diverse group of Request For Comments (RFC) documents. RFCs are a series of notes that contain Internet-oriented protocols. RFC documents also set forth ideas, implementation techniques, observations, studies, measurements, and clarifications related to the diverse set of specifications that collectively run on Internet Protocol (IP) based networks. Before we can discuss video communication over networks, we must understand how certain IETF protocols function, and how those functions must be modified to meet the unique needs of real-time media streams. Video Communications: The Whole Picture Application Application Presentation Peer-to-Peer Presentation Session Communications Session Transport Transport Network Peer- Network Peer- Network Data Link comm- Da