Apparatus and method for designing network

A method executed by a network design apparatus to add new wavelength paths to an existing optical network, the method comprising:

• determining whether all wavelength channels for main signals can deliver the main signals of the optical network;
• determining whether there are a specified number of wavelength channels that satisfy a specified chromatic dispersion condition, when it is found that one or more wavelength channels cannot deliver main signals;
• extracting a specified number of wavelength channels out of those satisfying the chromatic dispersion condition in descending order of optical SNRs thereof;
• and
• determining whether the extracted wavelength channels for main signal satisfy a specified condition of optical signal-to-noise ratios.

A computer-readable storage medium storing a network design program to add new wavelength paths to an existing optical network, the network design program, when executed by a computer, causing the computer to perform a method comprising:

• determining whether all wavelength channels for main signals can deliver the main signals of the optical network;
• determining whether there are a specified number of wavelength channels that satisfy a specified chromatic dispersion condition, when it is found that one or more wavelength channels cannot deliver main signals;
• extracting a specified number of wavelength channels out of those satisfying the chromatic dispersion condition in descending order of optical SNRs thereof;
• and
• determining whether the extracted wavelength channels for main signals satisfy a specified condition of optical signal-to-noise ratios.