| With the rapid development of telecommunication and information technique, a deeply transform is going on in the telecommunication field. Because of the fast increasing Internet, the traditional method of the circuit exchange will gradually be replaced by the way of wrap. The business classes of the customer also is changed into multifarious Broad Band business from single sound business, such as meeting television, long-distance education, broadcasting as needed, alternant multi-media communication and family shopping and so on. The way to pass the Broad Band information to the user and realize the point to point all digital multi-media communication is the focus in the communication field in the world. With the broad using of the technique of SDH, the bone net of the telecom net is basically accompanied by these factors, e.g. fiber, Broadband and digit. While the primary stimulant narrowband circle will be a big hindrance to block the broadband development of the current telegraphy net.Above all, in the first chapter of the paper, it mainly summarizes the technology of Access Network web connecting. It shows how the telecom network cannot meet with the operation needs at now and brings forward the conclusion that the user ring to be digitalized, broadband and integrated. In order to realize the requests, the technology of web connecting is a more mature and popular technique little by little. It comes out the advantages and the disadvantages about different the technology of web connecting, by contrast with the classifying and balancing. We can make a choice according to them in our practice! At present, the majority users connect with switchboard by a special doublet cord. According to statistics, there are 750,000,000 users on the Internet of the world. So we can say that he Internet is mostly doublet cord. The second chapter will say that part more deeply. The technology of copper wires access network into web is, have the PGS-Pair Gain System and xDSL on the traditional doublet cord circle, by means of the digital transmission. With the technology of modulation, we can have the bi-directional broadband transmission by the coaxial cable of the cabled TV. The chapter introduces the technology of how to connect with the web with high speed, especially the technology of ADSL. After some introductions of coding, modulation, the technology of error code controlling, we will study more deeply about the system of high-speed digital circle and the system of asymmetric digital circle, especially the technology of ADSL. In addition to, we have an introduction of the system of cable TV, which is on the beginning step.Though, copper wires access network web has many advantages, such as low investment, widely application, high down numbers, it had vital disadvantage on limited transmission bandwidth. Because of it's factors. With the increase of customers' requirement on bandwidth, the copper access network web with limited bandwidth resource must be "bottleneck effect" on information transmission between client and web. Leading optic fiber into web, not only change the "bottleneck effect" of copper wires access network web, but also can enlarge the cover domain of local network. It will develop well, and finally take place copper wires access network web. So, the 3rd chapter does a deep research on the technology of optic fiber into web from optic fiber transmission technology, network framework and so on. Both copper wires access network web and optic fiber access network web only can offer fixed service on connection to client PC. But wireless access network web has some advantage on active without comparing, especially on personal communication in the future, wireless access network web will has more important implication than wire access network web. The forth chapter beginning with the classification of wireless access network web, does a deep research on wireless local circle, mobileaccess network system, fixedaccess network system, satellite access network system, WLAN and compares advantages and d...
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