Design of long-distance telecommunication networks -The Telpak problem

The government procures long-distance circuits from communication carriers under a bulk-rate tariff referred to as Telpaks. While physical implementation of circuits is performed by the carriers, the arrangement of circuits into Telpaks for billing purposes is the government's responsibility. Since Telpaks were established in 1961, the government has arranged its circuits into Telpaks on a manual basis. As a result, it has never been able to achieve a minimum cost grouping for over 60 000 circuits among more than 3000 service points. Further, the problem of minimizing the cost of Telpaks has defied classical mathematical approaches because of the large number of service points and circuits. By applying heuristic design techniques, the systematic procedure which is described in this paper has been developed for automating the design of the government Telpak network. Its use has resulted in substantial cost savings over the manually obtained configuration.