Both data communication and telecommunication networks consist of nodes, links and network resources. Many studies deal with the design of optimal network topologies. In current methodologies, every node presents the same constraints and behavior, while in reality, the network resources vary. The research problem at stake is how to add central network resources (i.e., servers, gateways, network managers, probes, mainframes, etc.) in an optimal way, for example, such that the transmission delay will be minimized. For small networks or for a small number of resources, it is feasible to find the optimal locations of the resources by checking all the possibilities. This method cannot be applied to large networks, where a great many of resources are located. In such cases the problem turns into a difficult optimization problem that can be classified as NP-complete. We deal with both optimal and heuristics techniques to solve this problem.