Research And Design Of VoIP Media Gateway Based On Soft-switch

Next generation network, which is based on packet assemble network, is the hybrid network with multi-services in voice, date and video. VoIP is the outcome of this combination. In the foreseeable future, VoIP services will gradually replace the traditional telephone and eventually IP. More concern will be given upon developing and consummating the VoIP technology to substitute PSTN.Soft-switch is the core of the calling and controlling for the next generation network, which keeps the service access module of the switch as a separate physical entity, Media Gateway (MG).This thesis researches and designs media gateway system ISAM-V, which can provide access and control functions for VoIP and has the ability to have smooth transition to the next generation network.Firstly, this thesis analyzes the development and market prospects of the VoIP, introduces the basic principles, architecture and protocols of VoIP and discusses the media gataway and media gataway control protocol H.248/MEGACO. Then, based on the ISAM-V system of Alcatel Shanghai Bell, the architecture and the software of ISAM-V are designed. It offers the functions of system initialization, packet handling, call setup/release and parameter configuration. Then, thesis finishes the system testing work, and the testing result shows that ISAM-V can connect subscriber termination of PSTN and ISDN to IP network. Finally, the development tendency of the research in this thesis is summarized.