We investigate the problem of routing a large number of scheduled lightpath demands (SLDs) on a wavelength-division-multiplexing (WDM) transport network. SLDs are connection demands for which the startup and tear-down dates may be planned. Existing SLD routing algorithms are able to process only a limited number of demands. So, to process a large set of SLDs, we adopt a divide-and-reassembly approach. The set of SLDs is partitioned on the physical network into different subsets so that the number of demands of each can be processed with the existing routing algorithms. The solutions of the subsets are then assembled to form a global solution for the original set of SLDs. We evaluate the gain in terms of computation time, obtained by solution of smaller instances of the routing problem, and the performance of this approach in terms of WDM resources devoted to the routing solution on the basis of partitioning the set of demands.
© 2003 Optical Society of AmericaPDF Article