Design And Implementation Of The Hardware System In The Broadband Access Smart Switch

Ethernet has become the dominated technology in LAN, while it evolved from shared-media pattern to switch pattern with transmission speed being promoted as well. As all kinds of media information such as audio and video are being expressed, transmitted and managed in digital format, the customers' requirement of bandwidth rise increasingly, data network carry more and more service, include voice and video service, and cause computer network converge the telephone, broadcast and television service. With the application of the DWDM technology, bandwidth crisis has been released efficiently in the long-haul network, so the real bottleneck now is located in the access network. In order to resolve this problem, several technologies have been developed as solutions to such issue. Ethernet access technology is one of the most important broadband access technologies.This paper discusses the design and implementation of the gigabit access smart switch hardware in our broadband access system over Ethernet. It introduces the architecture of the switch, HOL, delay control, VLAN and spanning-tree algorithm, and Crossbar backplane and store-and-forward technology. It focuses on the system architecture and hardware realization of the gigabit Ethernet Switch we designed, which include the control module with MPC8241 embedded processor core and the switch module.This thesis consists of six chapters. The first chapter introduce the current status and tendency of the network development, and compare several access technology. The second chapter introduces the essence of the switched Ethernet and the Switch devices, import the definition of the smart switch, point out the position of our broadband access switch SW1000 in the whole system, and make the partition of the logic modules. The third and fourth chapters are the main parts of the thesis, explain the design thinking about the control module and switch module respectively, emphasize the work principle of every chips and the realization of all function in details. The fifth chapter introduces the methods of system debug and test, analyze the test results. The last chapter draws the conclusion, points out the improvement for current switch, and the future directions of the Broadband access.