Research On Session Mobility In Next Generation Network

At present, Internet telephone have dominated a large market share in the communications. SIP puts forward a set of IP phone system structure. SIP has some features, such as simple, easy to extension and the existing Internet application connected. So, this paper mainly adopts local extension to SIP the way to perfect its session mobility.Firstly, this article introduces SIP mobility and IP mobility research background and deeply analyzes the research status of mobility, the main method and the advantages and disadvantages of various methods. Based on the analysis of doing, we know consider mobility problems need to be combined with SIP mobility and IP mobility. Through such way, network layer and application layer can give full play to the advantage of their mobility. In this paper we adopt REFER method as the solution of SIP session mobility. This method can effectively reduce terminal transfer delay. This paper's consider is data transmission in session mobility process. We combined SIP message transmission of application layer and packets encapsulation and transmission of network layer and through the analysis and calculations of the processing delay and transmission delay,we can know which packets need to be resent. Thus we have proposed a reasonable compensation algorithm to improve data transmission during session mobility.For allows the user to better handle data already receiving. This paper puts forward the introduction of the RTSP(Real-Time Streaming Protocol) to make a whole solution. Clients can always control data broadcast by RTSP.This article to the session mobility compensation algorithm was detected by two stages to finish. First, we use EXOSIP2 system to simulate SIP session mobility method, the realization of REFER method through experiment verification method can be applied to SIP session mobility. And then we construct SIP session mobility model on the NS-2 simulation environment. We simulate the session mobility date flow which had been adopted the compensation algorithm and analyzed carefully RTP packets. The results show the detector can run as expected.