Synchronous digital transmission equipment and method

Abstract

The sync digital transmission equipment includes cross unit creating connection to the service access unit via the service bus to complete the service dispatching between service access units, clock unit providing the system with sync clock, and control unit controlling the cross unit and the clock unit to complete the system configuration and monitoring. The cross unit includes bus operation mode in at least one frequency, the clock unit provides at least one clock frequency backing up sync clock bus operation mode, and the control unit identifies information based on the bus rate the service access unit connected to the cross unit and allocates the service access unit, the cross unit with corresponding sync clock and selects corresponding bus operation mode. The present invention also discloses corresponding sync digital transmission method. The sync digital transmission equipment and method can raise bandwidth access capacity on the basis of traditional SDH or SONET equipment while maintaining forward compatibility.

Description

technical field [0001] The invention relates to optical transmission equipment in communication technology, especially a synchronous digital transmission (SDH, Synchronous Digital Hierarchy or SONET, Synchronous Optix Network) equipment and method. Background technique [0002] In the mid-1980s, optical fiber communication began to be widely used in communication networks, mainly focusing on point-to-point transmission and adopting a quasi-synchronous (PDH) transmission system. With the gradual formation and expansion of the optical fiber trunk network, users and services are constantly increasing. However, the PDH transmission system without uniform standard optical interface, incompatible with multi-vendor equipment, and limited transmission rate is obviously inconsistent with the development trend of optical fiber communication. [0003] For this reason, Bell Communication Research Institute of the United States proposed the concept of optical synchronous transmission net...

AI Technical Summary

Problems solved by technology

At present, the service bus of SDH equipment (synchronous digital transmission equipment) generally adopts the communication bus (Telecom Bus), and the bus frequency can be 38M or 77M, and the frequency of the communication bus is fixed and cannot be changed, so each service access unit 5 The bandwidth is also fixed (that is, the access capacity is also fixed), and cannot be expanded

With the development of telecommunication services, the access bandwidth of optical transmission equipment is required to increase, so only the development of new optical transmission equipment can meet the requirements. Generally, the method of increasing the bus frequency is used to increase the access capacity of each service access unit 5 , For example, use a higher rate low voltage differential signaling (LVDS, Low Voltage Differential Signaling) bus, but after doing so, the boards of various low rate buses developed in the past cannot be used on new equipment, while the high rate The bus cannot be used on old equipment, which caused customers to waste investment and resources in the past

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