A Uniform Negotiation and Delivery Mechanism for SIP-Based Conferencing System

In this paper we present a uniform negotiation and delivery mechanism for SIP-based conferencing system over IP network. With this mechanism rich innovative collaboration services can be developed conveniently to provide users with novel communication experience in IETF centralized conferencing (XCON) system. The mechanism adopts the extended SDP and offer/answer model as media description and negotiation mechanism. And it uses RTP/RTCP and extended MSRP as the media transport control protocols respectively for audio/video and various TCP-based data collaboration applications. In this paper, the requirement of the mechanism is revealed from a high-level design perspective. Then it is analyzed in detail by highlighting several prominent design choices.