Design And Implementation Of SIP-based VoIP Terminal On Embedded Platform

With the development of IP-based telecommunication technology and Internet wideband service, VoIP telephone technology superseded the conventional PSTN technology step by step in recent years, and becoming the development trend of voice communication technology. On the other hand, the form of which developed from Applications based on personal computer to system-on-chip intelligent terminal embedded system based on IP networks.The Session Initiation Protocol is an application-layer signaling protocol distributed by IETF for creating, modifying, and terminating session with one or more participants. By learning lessons of HTTP and SMTP protocols, reusing many of the header field, encoding rule, protocol procedures and authentication mechanism of HTTP, as a result of its far lower complexity, rich extensibility and better scalability, it is accept by the industry and becoming the best wide-used protocol, also, it is the core protocol of the NGN project.This thesis decribes the principle, core technology and development trend of IP communication technology in the first part. After that, it analyses the wide-used protocols of IP phone technology, including SIP used for signaling control, SDP for media parameters negotiation, and RTP for voice data real-time transporting. In the following charpters, it details the architecture and processing of design and implementation this terminal. It is implemented on the Broadcom 1100 series voice communication dedicated SoC platform, based on VxWorks real time OS, and controlled the system state machine by message queue mechanism.At last, this terminal passed the performance and compatibility test, complying with the RFC3261. And it is considered as stable, easily used and high compatible.