The Investigation Of PSTN Progress To The Next Generation Network

PSTN is the supporting network and contributing primary profits to the fixed network operation corporation. By the double functions of the demand and technique, the development of PSTN is facing the challenge of smart change. On the one hand, people'demand to network business presents the direction of diversification, totalization and individuation during the development of the society economic. On the other hand, the new technique revolution represented by the Internet is changing the telegraphic corporation's concept and frame system. In the future ten years, the quantity of the data business will the exceed the telephone business in the whole world scope, so result in the change of the frame system of the network and the syncretise of the multi-network has became the direction of the network's development. Under the above background, it is necessity that PSTN will progress to the next generation network.Next generation network is a very broad network concept, comprising the whole telegraphic area from exchange, connection, data carrying and moving to business and application. This Paper discusses the nest generation network, the technique comprises the soft exchange and IP Multimedia Subsystem (IMS).Making the PSTN network of Tianjin Netcom for example, the Paper investigates the progression from PSTN to the next generation network. On the basis of analysising the limitation of PSTN network on the network frame and the business presentation and the development of the next generation network, the Paper provides PSTN network's progress sign of fixed network intelligent, soft exchange network and the IMS network. On the basis of analysising the purpose, significance and limitation of execution of network intelligent, the Paper lucubrates Tianjin Netcom's innovation in network technique, business function, operating administration and the fast business application during the network intelligent execution. The Paper discusses the soft exchange's concept and the purpose to realize soft exchange during the progress phase to the soft exchange, and also investigates how Tianjin Netcom's PSTN network has been intelligent rebuilt progress to soft network. At the end, the Paper discusses the IMS's characteristic and the questions'IMS is faced, investigates the train of thought and steps which PSTN network of Tianjin Netcom progresses to IMS.