The Research On The Key Technology Of The Convergence Service Begtween IMS And CS

The content of the service platform within IP Multimedia Subsystem(IMS) is becoming richer while the massive constructions of IMS network are undertaking by mobile operator. At the same time, the prospective users of IMS domain are considered as an emerging market for traditional mobile operator. The convergence of IMS service and Circuit Switched Domain service could increase customers'loyalty to IMS service, which could extend IMS domain market as well. The service convergence means that whether customers access IMS domain or CS domain, they can experience same level quality of service. It is as same as the service convergence of Fixed Mobile Convergence. There are three different types of convergences within Fixed Mobile Convergence like terminal convergence, access network convergence, and service convergence. It is difficult to implement terminal convergence and access network convergence because of large amount existent customer. In contrast, service convergence could be implemented easier by adopting IMS technology to integrate all relative service platforms.In order to implement service convergence, the communication between IMS network and CS network should be achieved. Currently, all of mobile carriers can offer circuit based multimedia service by 3G network, however, IMS domain can provide more various and richer multimedia services. In order to implement service convergence, the intercommunication between signaling layer and media layer should be achieved as well. At present,3GPP international standard only defines Relationship and Mapping between SIP and ISUP, as well as SIP and BICC however, the adaptation and code/decode between the services of CS domain service and IMS domain service are not standardized yet. Thus, in this thesis the key technologies of intercommunication of video phone the between IMS and CS, and the relative technology standard of mobile carriers based IMS network and CS network are studied and evaluated. Then, the video phone signaling process is designed, and the improvement of current network equipments is proposed. Furthermore, though IMS network can provide flexible services, after many years developments of services in CS domain, mobile carriers have established relatively comprehensive service networks that based on mobile intelligence network technology and can provide various value-added services like voice, data, and multimedia services. This stimulates economic and social growth. As in a short time, the migration of these technologies to IMS domain completely is not possible, the convergence of service platform and the standardization of service between IMS domain and CS domain are becoming a crucial goal for mobile carriers to achieve. In this report, convergence of Service Broker is proposed, and how to achieve the functions of services transfer and service cooperation between domains by adopting Service Broker are studied and discussed.Lastly, the one number service solution of IMS and CS convergence is introduced. It is a classic and complicated convergence service. According to the research and analysis of current network technology, a low cost and easier implementation solution is designed, which is proved as feasible by a current cooperation experiment network between various network equipment providers. Then, based a Service Broker convergence platform an optimization solution is proposed, which proves that Service Broker is capable to increase implementation efficiency, optimize signaling process, and deduce service convergence cost.