Design And Implementation Of The Control On Media Resources In The Softswitch-Based MSC

Composite Mobile Telecommunication (CMT) is an All-IP Digital Cellular Telecommunications System, which is based on the interface of CDMA2000. It is independently developed and implemented by National Digital Switching System Engineering&Technical Research Center (NDSC) according to the requirements of the National 863 Project "Developing and Integrating of CDMA2000 Test System". This dissertation basically discusses the design and implementation of media resources control in MSC based on Mobile Softswitch according to CMT system.At first, this dissertation briefly explains the whole architecture of CMT system and introduces the Mobile Switching Center (MSC) that is based on IP-Connect and Mobile Softswitch. Then it describes in detail the architecture, function and calling control flow of Distributed Media Gateway Controller, which is one of the very important innovations and characteristics in CMT system. At last, it mainly discusses the management of circuit, vocoder and sound based on this architecture and calling control flow.In order to improve the utilization factor of circuit, it adopts many routing aritharithmetics in Circuit Distribute Controller for load sharing and three managed methods of circuit in Call server to reduce the possibility of occupying the same circuit. Furthermore, it sets up the internuncial mechanism by DPC primitive message to control calling over the signaling level. It discusses the deployed methods of vocoder in CDMA telecommunication based on IP and brings forward a kind of managed arithmetic. Compared with the traditional telecommunication system, this arithmetic can save vocoder and improve the quality of voice and accord with the developed trend of All-IP mobile telecommunication. Sound files are saved in FLASH of CMG Maintenance Center. After the system runns, they are outspreaded in memory and set up an index for quickly orientating the sound's data when playing. It brings forward the concept of combined sound files to improve the utilization factor of FLASH.The algorithms and flows introduced in this dissertation are already implemented by programs, and have a good effect in the test of CMT system.