Simple ILP approaches to grooming, routing, and wavelength assignment in WDM mesh networks

This paper presents novel integer linear programming (ILP) formulations for integrated traffic grooming, routing (GR), and wavelength assignment (GRWA) designs. The objectives are i) to find out the minimal number of electro-optical transceivers needed for the whole network or ii) to design networks with the minimal number of transceivers at the node which requires the most, i.e., a min-max relaxation of the previous objective. Results are presented for mesh networks with 6, 10, and 16 nodes. The straightforward formulation proposed enables the minimal number of transceivers to be found below one minute running time for 6 nodes while relaxed approaches are able to solve a 16-node networks within one hour. However, it was found that min-max based designs are far from reaching the most economical solution.