Bidirectional WDM self-healing ring network

摘要

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.