Patent ID: 6304349
Filing Date: 2001-10-16
Classification: H04J,H04Q

Abstract:
A communications network comprising processor means; a plurality of nodes; and a plurality of optical fiber links, each of said optical fiber links comprising means for transporting data on a plurality of channels, each of said channels characterized by a wavelength, w; node pairs, u, being selectively connected by a lightpath having a cost and comprising a channel in at least one of said links, each said lightpath having a common wavelength in each included link; the set of connections establishing a lightpath between pairs of said nodes to meet a defined data communications load, .delta.(u), being .DELTA.(u), where .vertline..DELTA.(u).vertline.=.delta.(u); said connections being established by said nodes in response to a set of configuration signals determined in said processor means from among admissible lightpaths, thereby to reduce the overall cost of establishing said lightpaths in meeting .delta.(u); said processor means determining said configuration signals by starting with an arbitrary set of configuration signals (p, w) and iteratively performing the stepsfor each node pair, u, determining a connection, c .epsilon. .DELTA.(u) that maximizes a lightpath-metric associated with the current configuration signals, andforming new configuration signals by setting (p(c), w(c))=(p, w), where(p, w) is an admissible lightpath for u such that the lightpath metric is minimized, until a predetermined stopping criterion is fulfilled, and then selecting the connections yielding the lowest cost.