Dynamic Assignment Of Wavelengths In Agile Photonic Networks

Abstract

In an automatically switched optical network, the wavelengths are assigned to optical path based on their intrinsic physical performance and on the current network operating parameters. The wavelength performance information is organized in binning tables, based primarily on the wavelength reach capabilities. A network topology database provides the distance between the nodes of the network, which is used to determine the length of the optical path. Other network operating parameters needed for wavelength selection are also available in this database. Once a bin corresponding to the path length is identified in the binning table, the wavelength for that path is selected based on length only, or based on the length and one or more additional parameters. The optical path performance is estimated for the selected wavelength, and the search continues if the estimated path performance is not satisfactory. Several available wavelengths are searched and of those, the wavelength that is most used along the optical path in consideration or alternatively network-wide is selected and assigned. This method helps minimize wavelength fragmentation. The binning tables may have various granularities, and may be organized by reach, or by reach, wavelength spacing, the load on the respective optical path, the fiber type, etc.

1 .- 24 . (canceled) 
     
     
         25 . In a automatically switched optical network, a routing management block comprising:
 means for storing wavelength performance information according to type, extent and granularity search criteria;   means for storing updated network resources information; and   a wavelength assignment module for determining the length of an optical path by searching said updated network resources information and selecting a wavelength for said optical path based on said wavelength performance information.   
     
     
         26 . A routing management block as in  claim 25 , wherein said wavelength performance information comprises a wavelength binning table with a plurality of reach bins, a reach bin comprising one or more wavelengths classified according to a reach range. 
     
     
         27 . A routing management block as in  claim 26 , wherein each said reach bin further comprises a plurality of load sets, each load set comprising one or more wavelengths classified according to a load range. 
     
     
         28 . A routing management block as in  claim 25 , wherein said wavelength performance information comprises a signal quality versus reach (Q-Reach) graph. 
     
     
         29 . A computer readable database medium having a binning table database for storing wavelength performance information and for causing a computer to process said binning table database so as to assign a wavelength to an optical path in a automatically switched optical network, said binning table database comprising:
 a plurality of reach bins, a reach bin storing one or more wavelengths classified according to a reach range; and   in each said reach bin, a plurality of sets, each set comprising one or more wavelengths organized according to a wavelength performance parameter.   
     
     
         30 . The computer readable database medium as claimed in  claim 29 , wherein said wavelength performance parameter is the effective load of said optical path. 
     
     
         31 . The computer readable database medium as in  claim 29 , wherein said wavelength performance parameter is the wavelength spacing available for said wavelength plan. 
     
     
         32 . (canceled)