A modified heuristic approach of logical topology design in WDM optical networks

This paper introduces a modified heuristic approach as a solution to the problem of routing, wavelength assignment (RWA), and traffic grooming when designing a logical topology given the network physical topology. The RWA problem is known to be the assigning of network resources (wavelengths, transmitters, and receivers) to successfully establish lightpaths in the Wavelength Division Multiplexing (WDM) optical network. The traffic grooming problem is the multiplexing of lower speed connection requests to high speed streams. The proposed heuristic is based on Dijkstrapsilas algorithm and it is a modification to the MSHT heuristic. For a given network physical topology and traffic pattern (traffic distribution between every node pairs), the objective is to design a logical topology and a routing algorithm so as to minimize both the average packet hop distance and amount of processing at each node. Two constraints are considered, namely, the number of wavelengths required to embed the resulting logical topology and the number of transmitters and receivers per node.