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arXiv · 1212.3981

Approximating Minimum-Cost k-Node Connected Subgraphs via Independence-Free Graphs

Joseph Cheriyan·Laszlo A. Vegh
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Abstract

We present a 6-approximation algorithm for the minimum-cost $k$-node connected spanning subgraph problem, assuming that the number of nodes is at least $k^3(k-1)+k$. We apply a combinatorial preprocessing, based on the Frank-Tardos algorithm for $k$-outconnectivity, to transform any input into an instance such that the iterative rounding method gives a 2-approximation guarantee. This is the first constant-factor approximation algorithm even in the asymptotic setting of the problem, that is, the restriction to instances where the number of nodes is lower bounded by a function of $k$.

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Joseph Cheriyan, Laszlo A. Vegh. 2012-12-17. Approximating Minimum-Cost k-Node Connected Subgraphs via Independence-Free Graphs. https://arxiv.org/abs/1212.3981

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