System and method for dynamic wavelength assignment in wavelength division multiplex ring networks

A method of assigning a wavelength to an incoming flow in communications network comprising steps of:

• grouping wavelengths in the network into collections of wavelengths;
• mapping each collection of wavelengths to one of several cases, wherein each of the cases is representative of a spatial relationship between existing traffic in a network and an incoming flow;
• selecting one of the cases to which the collections have been mapped by identifying which of the cases to which the collections of wavelengths has been mapped results in the fewest total number of optical-to-electrical (“OE”) and electrical-to-optical (“EO”) interfaces being added to the network;
• and
• selecting a wavelength from the collection of wavelengths corresponding to the selected one of the cases to be assigned to the incoming flow, wherein the selecting is performed such that a performance of traffic of the incoming flow is maximized and performance of existing traffic in the network is minimally affected.

A system for assigning a wavelength to an incoming flow in communications network comprising:

• means for grouping wavelengths in the network into collections of wavelengths;
• means for mapping each collection of wavelengths to one of several cases, wherein each of the cases is representative of a spatial relationship between existing traffic in a network and an incoming flow;
• means for selecting one of the cases to which the collections of wavelengths has been mapped;
• and
• means for selecting a wavelength from the collection of wavelengths corresponding to the selected one of the cases to be assigned to the incoming flow.