The economic addition of functionality to a network

Abstract

In the operation of communication and computer networks, it may become desirable or necessary to add a new function to the network through the placement of the corresponding electronic device within certain existing user locations. This will involve deciding which user locations will have devices placed at them as well as deciding an assignment of users to device locations. The objective when adding the new function is to choose these locations and assignments such that the combined cost of placing the devices and routing users to their assigned device locations is minimized. This problem, which we call the device placement problem, is closely related to the simple plant location problem and the p-median problem. Like these problems, the device placement problem is NP-hard, and thus it is highly unlikely that efficient methods for solving this problem to optimality exist.

We discuss and test several heuristic methods for the device placement problem, as well as a very efficient method for obtaining lower bounds. Our methods are based on relating the problem to a certain restricted spanning tree problem, which leads to conceptually easy ideas.

This research was partially supported by grants from the Natural Sciences and Engineering Research Council of Canada.

Partially supported by a Rhône-Alpes International Research fellowship.