Path level traffic grooming strategies for multi-objective design in WDM networks

In this paper, we develop a multi-objective network design model for the traffic grooming, routing and wavelength assignment (GRWA) in WDM networks. We consider and evaluate four traffic grooming strategies which are Point to Point (P2P), Point to Multi-Point (P2MP), Multi-Point to Point (MP2P) and Multi-Point to Multi-Point (MP2MP). The design objectives are to maximize the number of accepted communication requests (source-destination pairs) as well as to minimize the number of wavelength channel requirement. Both the design objectives are conflicted to each other; maximizing the number of accepted commodities will require a large number of wavelength channels while minimizing the number of wavelength channels will limit the amount of accepted commodities. To solve the multi-objective network design problem, we apply a fast and efficient optimization technique called “Fast Non-dominated Sorting Genetic Algorithm (NSGA-II)”. The simulation results show that traffic grooming with multiple sources/destinations are the most flexible and efficient grooming techniques that give wide-spread solutions on the objective space, than those solutions obtained from the P2P grooming technique in both objective values (i.e., number of accepted commodities and wavelength channels required).