| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a fault recovery method by which the fault recovery grain can optionally be set by switching a presently used path to a stand-by path only at the terminal point of the presently used path without specifying a fault position. SOLUTION: In the case of performing 1+1 protection between B and C of a path 32 with a node A as a start point and with a node D as a end point, a preset use fault recovery path 30 is set to a path B-M-C and a stand-by use fault recovery path 31 is set to a path B-N-C, first. Next, a virtual link with these two paths as a real entity is defined to set a path 32 to a path A-B-C-D via the virtual link. When the path 30 has no fault, the node B transmits the main signal of the path 32 received from the node A to both of the path 30 and the stand-by use fault recovery path 31, and the node C receives the main signal of the path 32 from the path 30. The node C monitors the fault of the path 30 and switches a space/time division multiple switch 24 so as to receive the main signal of the path 32 from the stand-by use fault recover path 31 when detecting the fault.</p> |
