Communication channel setting method variable bandwidth communication method, variable bandwidth communication device, transmission band determining apparatus, transmission band determining method, node device, and communication path setting system,

摘要

Bit rate is constant in the optical paths of all, the band variable communication method allowing effective use of the frequency band is provided. In the bandwidth variable communication method, when you change the network management device or setting, the light path through the plurality of communication devices, calculated or measured the optical signal quality degradation amount in the path of the light path, the optical signal quality degradation amount Of the transmittable modulation format, select the modulation format narrowest spectral band, the control means of each communication apparatus for an optical path route network management apparatus condition (bit / s) bit rate B and the desired between, on the basis of the selection result of the modulation format, and to exchange control information. The band variable communication apparatus receives the control information, based on the received control information, and is changed based on the control information the passband.