Design And Implementation Of Video Conference Based On SIP

With the rapid development of multimedia technology and network communication technology, multimedia communication services gradually hold the dominant position in the Internet application.H.323 and SIP aer the main signaling protocols which control multi-media sessions in a multimedia conference system over the packet network.H.323 is maturer than SIP in application,but SIP is rather simple, flexible, opening and extendable than H.323 which is complicated in implementation and extending and and costs much. As soon as SIP is released, it is cared and supported. The research on SIP-based videoconference system also noticable.This thesis analyzes the basic content of SIP, discusses its protocol stack and gives a method of implementation. Then it discusses the application of SIP in the multimedia conference, designs the application model of SIP-based videoconference System, and implements the terminal of UA and the control of conference and media signaling in the core of this system.Finally, the model testes and analyse, a conclusion is drawn which model can be used in a project after it is optimized and it can be studied in the future research.From what is mentioned above,we can form a detailed study to do the following:(1) First of all, the research of SIP and network architectureThe research of SIP and network architecture is the foundation of this paper,and the video conference models, protocol stack and extension are based on the SIP.(2) Secondly, the design of video conference model based on SIPTo design a good video conference system model based on SIP will help to accelerate the speed of the system development, reduce the difficulty and risk of the system development. System models will greatly influence the difficulty, progress and stability of the system development, and even decide the success or failure of system development. On the basis of understanding the actual network operation mode,we analyzed several kinds of video conference mo, choose a suitable model of the communication system, and puts forward a model of video conferencing system model,Based on the design of a good video conferencing system model of SIP, will help to reduce development speed system, the difficulty and risk system development. System models will greatly influence the difficulty of the open system, progress and stability, and even decide the success or failure of system development. In understanding the actual network operation mode, based on the analysis of several kinds of video conference models,and choose a suitable model of the communication system, and puts forward the whole model of the video conference.(3) Thirdly,to establish a suitable SIP stack for video conference based on JAIN stack.To design and implement a good SIP protocol stack is very crucial,the paper select JAIN as the SIP stack,established our own SIP stack by modify or add some function, and made it meet the need of the video conference. To choose JAIN SIP API as development platform, completed the design and realization of the user agent, conference server, register server and redirect server.(4) Finally, With JMF API as the development platform, to develop and implement the transmission and processing of audio and video stream.Through the research of JMF API and RTP , and combined with a specific project, this paper discusses and implements a audio and video transmission system, and made it as the network transmission module of the video conference system.