A heuristic logical topology design algorithm for multi-hop dynamic traffic grooming in WDM optical networks

Traffic grooming in wavelength division multiplexing (WDM) optical networks controls how to consolidate client calls with sub-wavelength data rates onto lightpaths. It can be classified into static or dynamic traffic grooming depending on whether the client traffic is static or dynamic. The principal problem in traffic grooming is to construct a logical topology to route client traffic over a given physical topology. For dynamic traffic grooming, the logical topology may be dynamically configured, or designed a priori given the stationary traffic demands between client nodes (and reconfigured on relatively large time scale, e.g., on the order of hours, to adapt to traffic demands changes). Both approaches have their pros and cons. This paper studies the latter case and develops a heuristic algorithm to design logical topology, constrained by client traffic blocking probability requirement and the maximum by-pass traffic amount allowed at each client node. We have compared logical topologies designed the heuristic and an ILP model. The heuristic performance is impressive.