# Approximating Rooted Steiner Network

Abstract : The Directed Steiner Tree (DST) problem is a cornerstone problem in network design, particularly, in the design of directed networks satisfying connectivity requirements. We focus on the generalization of the problem with higher connectivity requirements. The problem with one root and two sinks is APX-hard. The problem with one root and many sinks is as hard to approximate as the directed Steiner forest problem, and the latter is well known to be as hard to approximate as the label cover problem. Utilizing previous techniques (due to others), we strengthen these results and extend them to undirected graphs. Specifically, we give an $O(k^\epsilon)$ hardness bound for the rooted $k$-connectivity problem in undirected graphs; this addresses a recent open question of Khanna.
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Conference papers

Cited literature [16 references]

https://hal.archives-ouvertes.fr/hal-00709994
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Submitted on : Tuesday, June 19, 2012 - 5:55:08 PM
Last modification on : Thursday, June 18, 2020 - 12:32:04 PM
Long-term archiving on: : Thursday, September 20, 2012 - 2:41:43 AM

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bundit-august2.pdf
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• HAL Id : hal-00709994, version 1

### Citation

Joseph Cheriyan, Bundit Laekhanukit, Guyslain Naves, Adrian Vetta. Approximating Rooted Steiner Network. Symposium on Discrete Algorithms (SODA 2012), Jan 2012, Kyoto, Japan. ⟨hal-00709994⟩

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