,
Sariel Har-Peled
,
Dániel Oláh
Creative Commons Attribution 3.0 Unported license
We show how to construct (1+epsilon)-spanner over a set P of n points in R^d that is resilient to a catastrophic failure of nodes. Specifically, for prescribed parameters theta, epsilon in (0,1), the computed spanner G has O(epsilon^{-7d} log^7 epsilon^{-1} * theta^{-6} n log n (log log n)^6) edges. Furthermore, for any k, and any deleted set B subseteq P of k points, the residual graph G \ B is (1+epsilon)-spanner for all the points of P except for (1+theta)k of them. No previous constructions, beyond the trivial clique with O(n^2) edges, were known such that only a tiny additional fraction (i.e., theta) lose their distance preserving connectivity.
Our construction works by first solving the exact problem in one dimension, and then showing a surprisingly simple and elegant construction in higher dimensions, that uses the one dimensional construction in a black box fashion.
@InProceedings{buchin_et_al:LIPIcs.SoCG.2019.19,
author = {Buchin, Kevin and Har-Peled, Sariel and Ol\'{a}h, D\'{a}niel},
title = {{A Spanner for the Day After}},
booktitle = {35th International Symposium on Computational Geometry (SoCG 2019)},
pages = {19:1--19:15},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-104-7},
ISSN = {1868-8969},
year = {2019},
volume = {129},
editor = {Barequet, Gill and Wang, Yusu},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.SoCG.2019.19},
URN = {urn:nbn:de:0030-drops-104237},
doi = {10.4230/LIPIcs.SoCG.2019.19},
annote = {Keywords: Geometric spanners, vertex failures, robustness}
}