An algorithm for solving the Max-rwa problem

in wide all-optical WDM networks

A. Zyane1, 2, 3*, S. Pierre2, Z. Guennoun3

1 Département de maintenance industrielle, Ecole Supérieure de Technologie de Safi – E.S.T,

Université Cadi Ayyad, B.P. 89, Route Dar Si Aissa, Safi,- 46000 - Maroc

2 LARIM, Laboratoire de recherche en réseautique et informatique mobile, Département de génie informatique,

Ecole Polytechnique de Montréal, Montréal - Canada

3 L.E.C, Laboratoire d’électronique et communication, Ecole Mohammadia d’ingénieurs –

E.M.I, Université Mohammed V, Rabat, Maroc

* Corresponding author. E-mail:,,,

Received: 02 August 2005; revised version accepted: 10 February 2006


This paper proposes a new approach for routing and wavelength assignment in wide all-optical WDM networks with wavelength continuity constraint. Given a number of available wavelengths on each optical fiber, we seek to maximize the number of satisfied requests for connections. This is known as Max-RWA problem. In our approach, called MLL (RWA with Minimum Loaded Link), the routing is based on the search for the optimal path while trying to minimize the load on the links of the network in order to minimize the links’ capacity and then minimize the utilization of the network links. The wavelength assignment is based on a graphs coloring method using tabu-search. We tested our algorithm on known networks like the EONNET and NSFNET. Generally, our results are better with those provided by the existing solving approaches taken as reference.

Index terms- RWA, routing and wavelength assignment, WDM networks, optical routing.

© 2015