Method and device for estimating transmission quality of optical path

A transmission quality estimation method that estimates a transmission quality of a target path in a wavelength division multiplexing optical transmission system, the method comprising:

• storing path transmission quality values that respectively indicate transmission qualities of paths established between adjacent nodes in a first storage;
• storing an intra-node transmission quality value that indicates a transmission quality in a node device in a second storage;
• calculating a one-span path transmission quality value that indicates a path transmission quality at a wavelength of a target path based on corresponding path transmission quality values stored in the first storage with respect to a target span on a route on which the target path is established;
• estimating a transmission quality of the target path based on the one-span path transmission quality value calculated with respect to the target span and the intra-node transmission quality value stored in the second storage;
• obtaining a measurement value of a transmission quality of the target path;
• calculating a new intra-node transmission quality value corresponding to the target path based on the target path transmission quality value calculated with respect to the target span and the measurement value of the transmission quality of the target path;
• and
• updating the intra-node transmission quality value stored in the second storage using the new intra-node transmission quality value.

A transmission quality estimation device that estimates a transmission quality of a target path, the device comprising:

• a first storage configured to store path transmission quality values that respectively indicate transmission qualities of paths established between adjacent nodes;
• a second storage configured to store a node transmission quality value that indicates a transmission quality of a node device;
• an estimation calculator configured to estimate a transmission quality of the target path based on the path transmission quality values stored in the first storage and the node transmission quality value stored in the second storage and to calculate a node transmission quality value based on the estimated transmission quality of the target path;
• and
• an update unit configured to update the node transmission quality value stored in the second storage using the node transmission quality value calculated by the estimation calculator.