Optical path sharing protection method in DWDM optical transmission system

Abstract

The present invention discloses an optical pass sharing protecting method in DWDM optical transmission system. On two optical transmission units which requires to provide protecting node in the transmission system, two sharing protecting units with same structure and four input optical signal monitoring units which also have same structure form a protecting device. The invention has the advantagethat the operation between nodes is totally harmonized by the on-off state of signal. The coding / decoding and signal analysis are not required similarly to protection to switching protocol by APS. The protecting device of the invention has the advantages of simple structure, no effect to the service structure of existing OADM looped network, and no change to the structure of network device. The purpose of service protection can be realized through directly adding a sharing passage protecting chassis. Furthermore the automatic protection switching and recovering can be realized without protocol software management. The restriction of loop node number does not exist. The time for switching and recovering is irrelevant to the length of loop and node number. The protecting device of the invention also has the characteristics of strong extendibility, convenient upgrading and reconstruction of network, simple and reliable action, multi-point failure protection, etc.

Description

technical field [0001] The invention relates to an optical path sharing protection method in an optical transmission system, in particular to an optical path sharing protection method in a DWDM optical transmission system. Background technique [0002] At present, the main optical transmission technologies are SDH and DWDM. Compared with SDH technology, ROADM and OTN systems belonging to the DWDM category are in a relatively weak position in network protection and restoration technology. In terms of the importance of the transmission business undertaken by the network, they are all out of proportion. At present, the main DWDM protection technology is two-fiber unidirectional optical line protection and optical path protection based on concurrent selective receiving technology, while two-fiber bidirectional optical line ring protection is rarely used due to the risk of ring network self-excitation. A large number of shared protections used in SDH seldom appear in DWDM system...

AI Technical Summary

Problems solved by technology

In recent years, this optical channel sharing protection technology has made a breakthrough and has been recognized by the International Standards Organization. However, due to the limitation of technical patents, it has rarely been promoted.

However, some of the existing shared optical channel protection technologies require coordinated management of transmission protocols, which increases the complexity of the system and reduces the speed of protection switching; The complexity and construction cost also reduce the reliability of the system; some are still difficult to withstand the harm of self-excited oscillation of the loop, thus affecting the engineering application of this technology

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