With the publication of licenses for mobile 3G, mobile operators are building a large-scale R4 network. In the R4 network, core network used soft switch technology, separated the control and bearer. MSC server accesses another MSC server through BICC signaling, MGW accesses another MGW through TDM/ATM/IP. At present, China Mobile 2G PRBT network used the way of caller switch trigger, PRBT platform connects switch directly or through a Tandem Board, signaling share the road with the data. In the 3G R4 Network, it also used the way of caller switch trigger, but if the data separated from signaling.This thesis analyses the background in which the 3G network and the IP-based PRBT service, and on the basis gives the realization of media server module in IP-based PRBT System, and given the specific design and implementation.
