Research On Improvement Of QoS In IP Multimedia Subsystem

IP Multimedia Subsystem (IMS), a new architecture for convergence of fixed and mobile networks, is now paid wide attention. It provides the nest generation the multimedia services platform based on Internet Protocol and supports various access mode both on fixed and wireless network. IMS blazes a way to all IP network and multi-network merging services for current telecommunication system.It is very import for IMS to provide QoS assurece to mobile multimedia services such as data, speech, image and video. IMS should guarantee the QoS of real-time multimedia services both in mobility and wireless environment. Therefore, research on improvement of QoS in IP Multimedia Subsystem is of great importance.This thesis discusses a method to optimize the quality of service of IP Multimedia Subsystem using SigComp. After introducing IP Multimedia Subsystem and Session Initiation Protocol, the thesis analyses the characteristic of SIP when compressing. And then improves the LZW compressing algorithm and the self-adaptive Huffman coding algorithm in order to compress the SIP message in IMS. The algorithm in this thesis is simulated in Hammer Dex testing environment, verifies that the Quality of Service of IMS can be optimized by compressing SIP messages using improved LZW and self-adapted Huffman algorithm.There are many ways to improve the QoS of IP Multimedia Subsystem, such as policy-based IMS QoS and improving QoS of Internet Protocol. The study in this thesis discussed improving IMS QoS through compressing SIP messages in IMS.