Patent ID: 7720390

Claim:
An optical node device that switches an optical signal, wherein a preset section in which data transmission is possible without 3R relay is defined as a 3R section, an optical node device, being a source of a setting request for an optical path is defined as a source node, and an optical node device at an end point of the optical path is defined as a destination node, the optical node device that switches the optical signal comprising: a storing unit which stores 3R section information corresponding to topology information of an optical network to which the optical node device that switches the optical signal belongs; an identifying unit which identifies another optical node device which implements 3R relay among optical node devices through which an optical path from the optical node device that switches the optical signal to the destination node passes with reference to the 3R section information stored in the storing unit, when the optical node device that switches the optical signal is the source node; and a unit which requests 3R relay be implemented in the another optical node device identified by the identifying unit, when setting an optical path in which the optical node device that switches the optical signal is the source node, wherein an optical node device at a start point of the 3R section is defined as a 3R source node, an optical node device at an end point of the 3R section is defined as a 3R destination node, an optical node device, being a source of a setting request for an optical path, is defined as a source node, and an optical node device at an end point of the optical path is defined as a destination node, and when one optical node device is a 3R source node of any one of a plurality of different 3R sections overlapping on an optical path that passes through the one optical node device, and the one optical node device is not a 3R source node or 3R destination node of other 3R sections, the identifying unit is provided with: a comparing unit which compares the number of 3R relay implementations for both the case where the one optical node device functions as a 3R source node and where the one optical node device does not function as a 3R source node, with reference to the 3R section information related to an optical path from the one optical node device to the destination node; and a unit which, when the number of 3R implementations in the case where the one optical node device functions as a 3R source node is less than the number of 3R implementations in the case where the one optical node device does not function as a 3R source node, decides that the one optical node device is an optical node device that implements 3R relay based on a comparison result from the comparing unit.