IMS域的切换研究

Research on IMS Handover

基于IMS(IP Multimedia Subsystem)域的通信中由于切换层次的增多导致切换时间的增加,从而使得服务的中断时间加长,这影响了移动中应用的服务质量。在UMTS(Universal Mobile Telecommunication System)R6规范中的切换流程中,跨网络切换采用SGSN(Serving GPRS Support Node)之间的切换而GGSN(Gateway GPRS Support Node)不变,这会导致数据流在IP(Internet Protocol)网络中的迂回,并且多条信令跨网络传输影响了切换的速度,增加了网络流量和端到端延时。该文在现有切换流程上提出了跨GGSN的切换流程,缩短了媒体流在切换过程中的中断时间,并减少了漫游状态下的端到端媒体流引起的网络流量和端到端的数据延迟。

The multi-layers handover in communication based on IMS（IP Multimedia Subsystem）results in the long interruption time of application, which reduces the Quality of Service （QoS） of the system. The process of handover signaling in R6 adopts the handover between SGSNs when one MS moves from one network to another, which will lead to the bypass of the data among the networks and will aspect the efficient of the handover and add the network traffic. The process of handover is improved by a bander between GGSN. It can fast the handover process and reduce the end-to-end delay for the roaming MS and the traffic of the network.