Multi-service Access Router Control Board Design And Realization

In recent years, with the rapid development of Internet access technology, the 3G, WLAN, xDSL, PON, V24/V25, E1, ISDN and other wide and narrowband access technologies and the related access services have appeared. The diversification of the development of access technologies has brought great convenience to the network's construction. The network operators expected that the wide range of business can achieve seamless access on the same network device ,so that the operating costs can be reduced. Howerver, the convergence of multiple access technologies and the integration of various business are bound to bring serious challenges to n the multi-service access routers.This article discusses the key to veneer of the multi-service access routers--the master plate of design and implementation. The multi-service access routers with structure of the master plate and the modular combined board. The master plate is responsible for the business card of modular scheduling, interface manager, and the master plate itself will usually provide several network access interface. Therefore, design of the master plate is relatively complicated, it is the entire multi-service access routers designed to focus and difficult problem.This article first discussed in detail the functionality and overall design of the master plate, and then elaborated on the various functional blocks of the host board design and implementation. Which focuses on a dual-monitor backup design, adaptive heat exchange system design, external clock shaking filter design: dual-monitor backup is designed to monitor (monitor the boot process) to do a backup. When the main monitor program has been damaged, it start switching the system from a backup monitor the program starts by the controling of CPLD . Dual-monitor backup system designed to effectively improve the stability; Adaptive heat exchange system was designed to resolve the current heat exchange system heat unevenly, efficiency is not high the issues raised by a new, advanced automatic control based on temperature and power consumption of the heat exchange made law and the realization of devices; External clock filter take multi-level buffering and repeatedly adopted to receiving clock signal. The external clock filter discards the pseudo-signal (spike) of hold time being no enough in order to remove an external interference in carrying by the clock.This paper addresses the master plate in the same grade of master plate design of network equipment industry, in the low-power design, simplicity, reliability aspects of advantages and generally reached a high level. At the same time, its low-level design for the entire device down to this level of this indicator has made a major contribution to the final performance of a high economic cost. The design formed product and released, the orders for domestic and international markets continued, showing a high market value.