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arXiv · 2404.08972

Improved Approximations for Flexible Network Design

Dylan Hyatt-Denesik·Afrouz Jabal Ameli·Laura Sanita
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Abstract

Flexible network design deals with building a network that guarantees some connectivity requirements between its vertices, even when some of its elements (like vertices or edges) fail. In particular, the set of edges (resp. vertices) of a given graph are here partitioned into safe and unsafe. The goal is to identify a minimum size subgraph that is 2-edge-connected (resp. 2-vertex-connected), and stay so whenever any of the unsafe elements gets removed. In this paper, we provide improved approximation algorithms for flexible network design problems, considering both edge-connectivity and vertex-connectivity, as well as connectivity values higher than 2. For the vertex-connectivity variant, in particular, our algorithm is the first with approximation factor strictly better than 2.

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Dylan Hyatt-Denesik, Afrouz Jabal Ameli, Laura Sanita. 2024-04-13. Improved Approximations for Flexible Network Design. https://arxiv.org/abs/2404.08972

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