Network management system

Abstract

A repeater includes a reception part configured to receive an optical signal transmitted by wavelength division multiplexing from a preceding repeater in a path from a source to a destination; a determination part configured to determine the channel allocation of the signal received by the reception part by determining a bit rate and a modulation technique with respect to each of channels in the received signal; and a detection part configured to detect a prohibited channel not to be included in the optical signal to be transmitted from the repeater, based on the channel allocation and a predetermined criterion.

What is claimed is: 
     
         1 . A network management system, comprising:
 a control part configured to control operations of a plurality of repeaters;   a determination part configured to determine a channel allocation with respect to each of the repeaters by determining a bit rate and a modulation technique with respect to each of a plurality of channels in an optical signal transmitted by wavelength division multiplexing and received by each of the repeaters; and   a detection part configured to detect a prohibited channel not to be included in the optical signal to be transmitted from each of the repeaters, based on the channel allocation and a predetermined criterion.   
     
     
         2 . The network management system as claimed in  claim 1 , wherein the detection part is configured to detect a recommended channel allowed to be included in the optical signal to be transmitted from each of the repeaters. 
     
     
         3 . The network management system as claimed in  claim 2 , wherein the recommended channel forms the channel allocation so that the channel allocation causes a phase noise to be lower than a predetermined level. 
     
     
         4 . The network management system as claimed in  claim 2 , wherein the recommended channel does not correspond to the prohibited channel in each of relaying nodes between a source and a destination.