Locality-sensitive orderings and applications to reliable spanners

Arnold Filtser, Hung Le

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

6 Scopus citations


Chan, Har-Peled, and Jones [2020] recently developed locality-sensitive ordering (LSO), a new tool that allows one to reduce problems in the Euclidean space g.,d to the 1-dimensional line. They used LSO's to solve a host of problems. Later, Buchin, Har-Peled, and Oláh [2019,2020] used the LSO of Chan et al. to construct very sparse reliable spanners for the Euclidean space. A highly desirable feature of a reliable spanner is its ability to withstand a massive failure: the network remains functioning even if 90% of the nodes fail. In a follow-up work, Har-Peled, Mendel, and Oláh [2021] constructed reliable spanners for general and topologically structured metrics. Their construction used a different approach, and is based on sparse covers. In this paper, we develop the theory of LSO's in non-Euclidean metrics by introducing new types of LSO's suitable for general and topologically structured metrics. We then construct such LSO's, as well as constructing considerably improved LSO's for doubling metrics. Afterwards, we use our new LSO's to construct reliable spanners with improved stretch and sparsity parameters. Most prominently, we construct Õ(n)-size reliable spanners for trees and planar graphs with the optimal stretch of 2. Along the way to the construction of LSO's and reliable spanners, we introduce and construct ultrametric covers, and construct 2-hop reliable spanners for the line.

Original languageEnglish
Title of host publicationSTOC 2022 - Proceedings of the 54th Annual ACM SIGACT Symposium on Theory of Computing
EditorsStefano Leonardi, Anupam Gupta
PublisherAssociation for Computing Machinery
Number of pages14
ISBN (Electronic)9781450392648
StatePublished - 6 Sep 2022
Externally publishedYes
Event54th Annual ACM SIGACT Symposium on Theory of Computing, STOC 2022 - Rome, Italy
Duration: 20 Jun 202224 Jun 2022

Publication series

NameProceedings of the Annual ACM Symposium on Theory of Computing
ISSN (Print)0737-8017


Conference54th Annual ACM SIGACT Symposium on Theory of Computing, STOC 2022


  • $2$-hop spanners
  • Doubling Metric
  • Minor Free graphs
  • Reliable Spanners
  • Ultrametric cover
  • ocality-Sensitive Orderings

ASJC Scopus subject areas

  • Software

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