Research On Appliance And Implementation Of H.248

From 1990s, IP technology, especially Internet, has been developed rapidly and data service has become the dominant one in networks. Also, the transmission and service in Internet has stepped into that of in telephony networks, too. The barrier between traditional telecommunication networks and computer networks has become not so distinct. Communication networks have been developed very rapidly and contents of service have been varying continuously. NGN was put forward in this background. IP was utilized as its key technology in its network layer and some other technologies in Internet were applied too. In addition, it took the ripe network management technology in traditional telecommunication networks, thus integrating the advantages of traditional telecommunication networks and Internet together and making a kind of manageable networks. Soft-switching is the key technology in NGN. Here, traditional gateways are separated into Media Gateways(MGW)and Media Gateway Controllers(MGC). Thus, the controlling is integrated into the networks. Media Gateway Controlling Protocol H.248 was born in 2000 under this background and developed step by step. It is the standard for the communications between MGC and MGW and MGC controls the services on MGW according to this protocol. Recent two years, several big domestic R & D centers were busy with the relevant implementing tasks with H.248. However, the outcomes were not so satisfactory.Towards the above status, based on the full and detailed introduction of the important concepts of H.248, such as Termination, Context, Command, Descriptor and Package, Transaction and Message, this thesis discusses the key appliance points of the protocol deeply. Also, we introduce our specific design method of implementation of H.248 in next generation networks (CDMA2000 core networks) according to the"3GCN"project in ZTE.In the thesis, we discuss the construction of software modules in details in the project and analyze the design of particular processes in H.248 module, including relevant important data structures, algorithms and processing procedures. From these, readers can understand the details about the design explicitly. In Chapter 5, based on the testing outcome the author attained in the real network circumstances, we can demonstrate the final success of the scheme. This accomplishment has filled the blank area in this field at home. In addition, with the combination of the other techniques, this success has made ZTE's soft-switching products the leading ones in China and even all around the world. It will definitely improve the world's research and design of NGN, and a new tide of concerning NGN's appliance will emerge throughout the world.