An approximation algorithm for minimum-cost network design

Abstract

This paper considers the problem of designing a minimum cost network meeting a given set of traffic requirements between n sites, using one type of channels of a given capacity, with varying set-up costs for different vertex pairs (comprised of a fixed part plus a part dependent on the pair). An approximation algorithm is proposed for this problem, which guaranteed a solution whose cost is greater than the optimum by a factor of at most log n (and constant in the planar case). The algorithm is based on an application of the recent construction of light-weight distance-preserving spanners.