A Tabu Search algorithm for the optimisation of telecommunication networks

A Tabu Search (TS) algorithm is presented for topological optimisation of broad band communication networks whose structure is based on a single exchange and on a number of multiplexing centres. Considering the high cost of the ®ber optic cable, the network architecture is a minimum spanning tree. The optimisation problem is reduced to choose the number and the locations of the multiplexing centres. This leads to model the network by a binary string in which ones and zeroes indicate activation or non-activation of multiplexing centres in the nodes. A TS algorithm has been implemented using a dynamically changing tabuÿtenure, a frequency based long term memory structure and an aspiration criterion. Extensive testing over networks of various sizes and con®gurations is made in order to choose the best values of the parameters. The performances of the algorithm are compared to those of other more traditional techniques. Ó 1998 Elsevier Science B.V. All rights reserved.