Abstract: A cost of a path may not be the only factor in searching for a path solution in a network. For example, some applications are delay sensitive and require finding a path that does not exceed a latency constraint for the entire path. Accordingly, a method and corresponding apparatus for searching for a path solution in a network is provided that identifies combinations of partial paths that satisfy an end-to-end path constraint, compares attributes of the combinations of partial paths, prunes the combinations of partial paths based on results of the comparing to identify candidate combinations of partial paths, and selects a candidate combination of partial paths as the path solution. By pruning combinations of partial paths, considerable is saved compared to exhaustive comparing of every possible combination of partial paths and scalability is achieved.

Abstract: Having a fast method to perform impairment evaluation is useful for many networks. A method or corresponding apparatus according to an example embodiment of the present invention maintains a traffic engineering database of values representing characteristics of links in the network through storage of integer values representing advertised optical signal capabilities of links between the multiple optical nodes. The example embodiment determines a path through the network for optical wavelengths to be supported by the links represented in the database as a function of evaluating optical signal characteristics at each link along a possible path using the advertised optical signal capabilities and provides a selected path meeting an acceptable integrity of the optical wavelengths to a path establishment module to establish the path through the optical network. Example embodiments significantly reduce computational complexity associated with impairment evaluation and path selection in an optical network.

Abstract: Having a fast method to perform impairment evaluation is useful for many networks. A method or corresponding apparatus according to an example embodiment of the present invention maintains a traffic engineering database of values representing characteristics of links in the network through storage of integer values representing advertised optical signal capabilities of links between the multiple optical nodes. The example embodiment determines a path through the network for optical wavelengths to be supported by the links represented in the database as a function of evaluating optical signal characteristics at each link along a possible path using the advertised optical signal capabilities and provides a selected path meeting an acceptable integrity of the optical wavelengths to a path establishment module to establish the path through the optical network. Example embodiments significantly reduce computational complexity associated with impairment evaluation and path selection in an optical network.

Abstract: A cost of a path may not be the only factor in searching for a path solution in a network. For example, some applications are delay sensitive and require finding a path that does not exceed a latency constraint for the entire path. Accordingly, a method and corresponding apparatus for searching for a path solution in a network is provided that identifies combinations of partial paths that satisfy an end-to-end path constraint, compares attributes of the combinations of partial paths, prunes the combinations of partial paths based on results of the comparing to identify candidate combinations of partial paths, and selects a candidate combination of partial paths as the path solution. By pruning combinations of partial paths, considerable is saved compared to exhaustive comparing of every possible combination of partial paths and scalability is achieved.