IMS-Based Audio Conference Server

IMS is a subsystem forwarded by 3GPP to surport the IP multimedia service.IMS adopts the SIP Protocol as the core Protocol.it has done the Further decomposition to the function of the control layer, Realized the separation of the Call Session Control Function and the MediaGateway Control Function,and made the network frame more open and flexible.The amalgamation scheme that based on IMS is recognized by people. beacause IMS has two basic point: one is the technical Convergence point—IP.the other is the service Convergence point—multimedia. The next-generation network that based on IMS is the trend in the future.SIP is an application layer controlling signaling protocol forwarded by IETF (Internet Engineering Task Force). It can be used to create, modify, and finish one or more session. The SIP is defined for providing advanced telecommunication service on Internet. SIP will be key control protocol of IMS and make great effort to large-scaled business application.The Audio Conference System is IMS-based. We adopt the SIP protocol as the main protocol to developed The communication platform. The system connects many types of the multimedia terminals together through LAN and WAN,for example,the mobile phone,IP phone,the network softphone and so on,to constitute a all-around network platform which amalgamating the personal and conference service together. the project is devided into server team and terminal team. In the server team, I designed the server software, implemented the communication flow, and did the research and development of the audio part.The conference service can realize the Multi-party communication. Conference can be used in a variety of types of streaming media communications.for example, the Audio, the video and the text. As the conference service could provide the real-time and quality assurance, More and more conference applications are developed by people,for example, the Voice chatrooms, network games and so on. Chapter 5 is the core part of the paper. This chapter details the conference Server System software architecture design and implementation, and the function of the conference system. The server System is composed of the application server,the signal server, the media server and the audio-mixed server. In the subsections we have introduced the function, structure and the detailed design of each server,including the SIP protocol stack offered by VOCAL,the Design and Implementation of the message conversion and Control Module, the communication flow, the Conference Management and Control Strategy.