Based On The Sip Network Multimedia Communication Session System Design And Implementation

Today, the network plays a very important role in our society. We can supply kinds of services for our production and life through network. As 3G times approach, there are some revolutionary changes in transfer, service and application of networks. A lot of network technologies get rid of stale and bring forth the fresh. These technologies will become impetus of the new generation network's development.SIP (Session Initial Protocol) is introduced as the next generation multimedia transfer kernel protocol by ITEF (Internet Engineering Task Force). Its main purpose is to solute the information command control and soft switch in IP networks. So it can be a platform of increment operation in the industry such as telecom, bank, finance, and so on. The content of this subject is application of IMS base on SIP protocol. This paper introduces SIP from three aspects-command analysis, protocol criterion, realization mechanism. As the same time, this paper compare SIP and other protocol, and point out the advantage and the infection for the next generation network.In the rear chapters, the paper introduces the network multimedia communication session system which based on SIP stack. It introduces system structure design and requirement analysis. It emphasize particularly on Group Manage module, Presence module, Instance Message module, Register module, and POC (PTT over Cellular) module. On the mind of system design, it main concern with module levels, module interface and module work flow. On the mind of system realization, it main concern with code executed flow, the difficult when realization and how to solute these difficult. One of the emphases is the module witch is established in this paper. After that, the paper also introduces the test process about this system from beforehand condition, message sequence and function of system.The subject also does research on the environment of programming and platform. It analyzes the same points and different points when system runs in different platform.At last, the paper investigates the foreground about this subject and gives some suggestions about network multimedia communication session system which based on SIP.