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arXiv · 1009.5734

Approximability of Capacitated Network Design

Deeparnab Chakrabarty·Chandra Chekuri·Sanjeev Khanna·Nitish Korula
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Abstract

In the {\em capacitated} survivable network design problem (Cap-SNDP), we are given an undirected multi-graph where each edge has a capacity and a cost. The goal is to find a minimum cost subset of edges that satisfies a given set of pairwise minimum-cut requirements. Unlike its classical special case of SNDP when all capacities are unit, the approximability of Cap-SNDP is not well understood; even in very restricted settings no known algorithm achieves a $o(m)$ approximation, where $m$ is the number of edges in the graph. In this paper, we obtain several new results and insights into the approximability of Cap-SNDP.

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Deeparnab Chakrabarty, Chandra Chekuri, Sanjeev Khanna, Nitish Korula. 2010-09-29. Approximability of Capacitated Network Design. https://arxiv.org/abs/1009.5734

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