Related Standards

In addition to RTP, a complete system typically requires the use of various other protocols and standards for session announcement, initiation, and control; media compression; and network transport.

Figure 1.1 shows how the negotiation and call control protocols, the media transport layer (provided by RTP), the compression- decompression algorithms (codecs), and the underlying network are related, according to both the IETF and ITU conferencing frameworks. The two parallel sets of call control and media negotiation standards use the same media transport framework. Like-wise, the media codecs are common no matter how the session is negotiated and irrespective of the underlying network transport.

Figure 1.1. IETF and ITU Protocols for Audio/Video Transport on the Internet

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The relation between these standards and RTP is outlined further in Chapter 3, The Real-time Transport Protocol. However, the main focus of this book is media transport, rather than signaling and control.