Based On Softswitch Technology 3g All-ip Network

With the ever increasing penetration of IP technology and the tremendous growth in wireless data traffic, the wireless industry is evolving the 3rd Generation (3G) core networks (CN) towards all IP technology。Universal Mobile Telecommunication System (UMTS) is expected to become a dominant network for 3G wireless system。Standardized by 3GPP, UMTS Core Network is built based on SoftSwitch with a evolution of R99,R4,R5,R6 towards all IP_based architecture。This thesis shows the motivation for the evolution towards all IP based architecture and discusses how to implement it。To offer next generation services, 3GPP is specifying an IP Multimedia Subsystem (IMS) in UMTS R5/R6, which is adjunct to the Packet Switched (PS) CN。The Session Initiation Protocol (SIP) has been chosen by the 3GPP as the main signaling protocol in the IMS。This paper will show the control architecture of the IMS, and discuss where SIP is used and the signaling process of Mobile Origination is discussed in great detail to show the interaction between the various components of the IMS network。However, new value added applications have new/high service requirement which cannot fulfilled by the existing "best effort"Internet Protocol。Quality of Service (QoS) is one of the key problems to be solved for All IP_based mobile network, IP QoS mechanism must be applied in the IMS。In this thesis, a solution using Differentiated Service (DiffServ) model in IMS to support QoS of data path is discussed。In control path, we discuss the Policy_Based Networking (PBN) mechanisms for QoS control in the UMTS。The limitations of the current state of the standardization are explained and an extension to provide Policy_Based end to end QoS control in multi-operator environments is disscussed。In the end, followed a discussion about the service architecture which based on the IMS, and some examples of how this architecture can be used to provide advanced services is proposed。...