All-optical multipoint-to-point routing in WDM mesh networks

In this article, the routing and wavelength assignment (RWA) problem for supporting multipointto-point communications in all-optical WDM mesh networks is investigated. Two efficient algorithms, namely Reverse Shortest Path Tree routing (RSPT) and kBounded Edge Disjoint Path routing (EDPR), are proposed. We proved that the problem of minimizing the total cost while establishing a multipoint-to-point session can be solved in polynomial time of O(|V |log|V |+ |V | + |E|) by the RSPT algorithm, where |V | and |E| denote the number of nodes and the number of edges in the network respectively. Nevertheless, the solution provided by the EDPR algorithm produces a significant reduction in the maximum number of wavelengths required per link (i.e., the link stress) for a multipointto-point session compared to RSPT algorithm. EDPR algorithm can also approximate to the optimal total cost with a ratio of k. Simulations are done to assess these two algorithms. Numerical results demonstrate A preliminary version of part of this work was presented in [17] at IEEE LCN 2009, Zürich. Fen Zhou, Bernard Cousin IRISA, Campus de Beaulieu, Rennes 35042, France Tel.: +33-299842537 Fax: +33-299847171 E-mail: {fen.zhou, bernard.cousin}@irisa.fr Fen Zhou INSA de Rennes, 20 Avenue des Buttes de Cöesmes, Rennes 35043, France Miklós Molnár LIRMM, University Montpellier II, 161 rue Ada, Montpellier 34392, France E-mail: {miklos.molnar}lirmm.fr Bernard Cousin University of Rennes 1, Campus de Beaulieu, Rennes 35042, France their efficiencies in supporting multipoint-to-point communications in all-optical WDM networks.