Design And Implementation Of PoC System Based On IMS Network

Now with the widely applications of Internet and the quick development of telecommunications, the communications is increasingly abundant. This drives the appearance of new telecommunication technologies and services. In 3GPP the Push-To-Talk over Cellular (PoC) service has been listed as one of the most important IP Multimedia Subsystem (IMS) applications.With the background of IMS, this thesis takes PoC, the new mobile value-added service as the research aim. The network architectures of the PoC system, the PoC client system in particular, are given deep research. And the design of PoC service at PoC client is introduced.Above all, this thesis gives domestic and overseas condition, correlation concepts, and major users of PoC. An overview of PoC services and logical structure are introduced. The implementation scheme of PoC service based on IMS is discussed prominently with the analysis of IMS system structure.Then according to the network architectures, this thesis gives a thorough analysis of PoC system including PoC serve and PoC client, especially the system module functions and system structure of PoC client. Meanwhile this thesis presents PoC client signaling exchange flow by using sequence diagrams and statechart diagrams in UML.Finally, according to the peculiarities of oSIP, the most popular SIP protocol stack, the design of PoC service at PoC client based on oSIP protocol stack is introduced. The program builds transactin to transfer oSIP Parser and operates according to the state transfemation of finite state machines for the implementation of PoC client system.