NGN Design And Implementation Of Teleconference System Based On SIP

With the development of the information technology and the request of getting information sooner and sooner, VOIP technology, which transmits multimedia information through IP network, has been developed a lot. Teleconference system provides an approach for remote communication and it can satisfy the demand for varieties of vocation. It is rapid and little cost, which has been agreed to by people.Nowadays, most the teleconference systems are based on H.323 protocol. SIP(Session Initiation Protocol) was established by IETF in 1999. IETF also established RFC4353 about teleconference model criterion, which promoted the development of SIP teleconference. The framework of SIP is simple and it can be easily implemented and conveniently applied. The unique controlling by the third party provides necessary condition for realization of teleconference.Depending on analysis of SIP, this paper puts forward a rational teleconference system design project. In the conference model, we make use of tightly coupled model and effectively reduce the load of conference server. In the function design, the server provides varieties of conference, such as Schedule; Meet me, Immediate conference and Multi-party communication. Also the server provides point to point communication, IVR and searching. In the model division, the system is logically divided into several big modules, and each big module contains some small modules. This layer upon layer way presents the realization of the teleconference in detail. At the same time, this dissertation improves the mixing algorithm; meanwhile through IPP software of Intel we greatly enhance the coding and decoding speed. Then the quality of communication in the meeting is greatly guaranteed.At last, teleconference system based on the previous design was successfully achieved. Through practical experiments, the whole teleconference system is functionally perfect and stable, realizing the goal of the design.