Patent ID: 8600229

Claim:
A shared protection method in a wavelength division multiplexing (WDM) loop network, wherein the WDM loop network comprises at least one node, and each node is divided into a multiplexing segment layer, a channel layer and a sub-wavelength layer, and the shared protection method comprises: A, respectively detecting the multiplexing segment layer, the channel layer and the sub-wavelength layer of each node; B, generating, with a detection point, fault information when at least one of the multiplexing segment layer, the channel layer and the sub-wavelength layer goes wrong and determining, with a controller of each node, a protection control state of the present node according to the fault information and notifying a corresponding executor, wherein the protection control state comprises service adding, service passing through, and service dropping; and C, controlling, with the executor of each node, the corresponding node to switch to the protection control state determined in step B, wherein the step B is performed by the following steps: Bl, the detection point generating the fault information when at least one of the multiplexing segment layer, the channel layer and the sub-wavelength layer goes wrong, and notifying to a fault related node; B 2 , a node controller of the fault related node notifying the fault information to the node controllers of the other nodes through a multicast signaling; and B 3 , each node controller obtaining the protection control state of the corresponding node through a shared protection switching protocol and notifying an executor of the corresponding node.