With the popularization of computer, the data communication requirement of human beings increases day by day. The terminal devices such as fixed - line telephones, Cell Phone, TV and so on, realized by replacing simplex voice with multimedia, could be the dream of everyone associated with network, anytime and anywhere. In the eyes of service provider of telecom, the monopolization posture of them is destroying and some other new service provider is changing the telecom world. The traditional service provider must change their situation. Under the competition, service becomes the keystone. Who can provide service with inexpensive, flexible and individuation, who will win! Because of the improvement of computer technique, network technique and software technique, data service and traditional voice service must syncretize into each other. We must integrate the telecom network, computer net and cable TV net into a common one. This common point is IP. However, at present, the data network based on IP has some disadvantages when it is used in voice or video multimedia service. The crucial reason is the bandwidth is not enough and QoS is also a problem. All in all, because of the improvement of technique, the competition of the service provider and the requirement of human beings, the telecom is improving. Because of this, the conception of NGN (Next Generation Network) appears and it is improved continuously.In this dissertation,it describes the development and status of networks at present and the conception of NGN development. Then, in the following chapters it describes the knowledge about NGN and mainly to show the research of us. Aim to establish the Network Accessing Module based on NGN, IAD800 provides a bran-new structure. At present, it is one of the most advanced equipment in the telecom field of the world.The core of IAD800 is MU500, a module with double CPU. One is used to deal with the wideband service and the other for narrowband service and the whole board control.It researched the structure and the status in network of IAD800 and MU500. For MU500, it's main to analyze the module functions and the method to achieve. For the service board in the IAD800 system, will not introduce the details, including xDSL, PSTN, IP and DDN service boards. One other importance of the dissertation is that introduce the net and the signals carried by the buses from the black plane (Ports of... |