WDM-PON Design Model Based on the Minimum Spanning Tree Search over Delaunay Triangulations

Abstract

The problem related with the optimization of a DWDM-PON can be approached in many different ways. The most cost-sensitive parameter for PON design is the length of optical fiber and, in a lower grade of sensitiveness, the number of distribution nodes, like the AWG employed for channel multiplexing/demultiplexing. The first step for finding the topology which minimizes the network deployment cost is choosing the proper way the users connect to the optical distribution network. One of the facts related with the optical distribution network topology is the users' clustering and the way such clusters connect with each other and with the central office. This paper presents a model for clustering users employing a Voronoi's graph partition. That way the clusters' centers could be linked to each other employing a Delaunay triangulation, which corresponds to the dual graph of the Voronoi partition. Provided that the Euclidian Minimum Spanning Tree (EMST) of the graph linking the clusters' centers is a subset of a Delaunay triangulation, through the use of heuristics it is possible to search the optimal Delaunay triangulation and its correspondent optimal EMST.