The Distributed Router Cpu Kouban Hardware Design And Realization

With the rapid development of information technology, and the dramatically increase of network bandwidth, the main component route r on the network need to keep upgrading. In the past, people has focused on the data forwarding plane on the router's research, by constantly upgrading technology, we has improved the router's forwarding bandwidth and business performance. In contrast, control systems has been insufficient attention. Master control board still concentrated control the routing protocols and initialization process, and take up a lot of bandwidth resources of the backplane, so the efficiency and reliability of the router system have been seriously affected.In view of the problems faced by the centralized control, after analysed the existing router control system in the essay, we adopted a distributed control method and integrated a CPU processor in the interface board, Some control service message is assigned to the forwarding unit, thus the interface board managed their own. Load sharing between the system control unit and forwarding unit can overcome the performance bottleneck of a single hardware, reduce the control unit overload, and improve the reliability of the router. Specifically, we designed a CPU master-slave processor system, the system is suitable for router control board and interface board. In the hardware design, MPC8548E has been selected as the CPU, MPC8548E managed other equipment of the system through the PCI bus and communicated through the Ethernet port and serial port. In addition, because there were many interactive task between the CPU system and other modules, We have specially chosen a CPLD logic to assist the MP48548E.In addition, in the application of modern high-speed digital circuits, one of the bottlenecks is the simultaneous switching noise in printed circuit board design. A reliability test method applied smiultaneous switching message and temperature stress to circuit board is introduced in this paper, this way can effectively expose the simultaneous switching noise problem in circuit board. By means of the noise test and impedance analysis, a abnomal problem discovered by the way has been analysed and studied, Through the optimization of the decoupling capacitor and the power supply impedance, the smiultaneous switching noise is suppressed in the circuit board, and the problem is resolved perfectly. At the end of the paper, some methods and suggestions for the suppression of the smiultaneous switching noise are provided during PCB design.