Bidirectional wavelength division multiplexing self recovering ring network

Abstract

A bidirectional WDM self-healing ring network is provided and includes an outer ring network and an inner network for processing N units of optical signals and for performing a protection switching by using the outer ring network when the inner ring network suffers a link failure. Each node of the ring network includes optical add / drop multiplexers positioned in the inner ring network and the outer ring network; a demultiplexer and a multiplexer having a capacity of 1xN, respectively; a pair of switching devices extending through the outer ring network and the inner ring network and is positioned between the optical add / drop devices and an optical fiber link connected to other node; and, a plurality of WDM filters positioned at both ends of the optical add / drop multiplexers, such that when a link failure occurs in the optical fiber link, the WDM filters transfer optical signals processed in the ring network including the WDM filters to one end of the optical add / drop multiplexer connected to the WDM filters, and transfer optical signals processed in the other ring network excluding the WDM filters to a WDM filter connected to the other end of optical add / drop multiplexer, without passing the optical signals through the optical add / drop multiplexer connected to the WDM filters.

Description

technical field

[0001] The present invention relates to an optical network, in particular to an optical network using WDM (Wavelength Division Multiplexing) technology. Background technique

[0002] Since WDM technology can transmit multiple optical signals through a single strand of optical fiber, it is already possible to transmit multiple very high-speed and large-capacity stored optical signals. With the aid of the exchange of add / drop optical signals in the optical layer, an optical network can be constructed based on WDM technology.

[0003] WDM optical networks are generally classified into ring networks using optical add-drop multiplexers and mesh networks using optical cross-connects. The WDM optical network transmits very high-speed mass-stored data through each optical fiber, thus requiring the WDM optical network to efficiently handle any undesired system failures. In the case of a mesh network, nodes of each optical network are connected to each other through ...

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