Patent ID: 9473834
Filing Date: 2016-10-18
CPC Classification: H04J,H04L,H04Q

Claim Text:
1. A method of routing and spectrum assignment for a traffic request of x sub-carriers of a super-channel in an optical communications network having nodes for bandwidth variable wavelength switching, the method comprising: checking whether there is an existing super-channel having the same source and destination as in the traffic request, and having sufficient potential sub-carriers for the traffic request which are not currently active, and for which link resources are available; if so, selecting and assigning x of the potential sub-carriers for the traffic request; otherwise, if sufficient such potential sub-carriers are not found, then identifying possible paths for a new super-channel having at least x sub-carriers for the traffic request; and selecting a path for the new super-channel from the identified possible paths and assigning x sub-carriers of the selected path for the traffic request; wherein identifying the possible paths for the new super-channel comprises identifying possible non overlapping paths having available link resources for x sub-carriers and not overlapping in spectrum with potential sub-carriers for other super-channels on any part of the possible paths; and wherein if no possible non overlapping paths are found, identifying overlap paths using spectrum overlapping with that of potential sub-carriers for other super-channels, and wherein selecting the path for the new super-channel comprises selecting from the identified overlap paths.