Multipath Spanners - Inria - Institut national de recherche en sciences et technologies du numérique Access content directly
Conference Papers Year : 2010

Multipath Spanners


This paper concerns graph spanners that approximate multipaths between pair of vertices of an undirected graphs with $n$ vertices. Classically, a spanner $H$ of stretch $s$ for a graph $G$ is a spanning subgraph such that the distance in $H$ between any two vertices is at most $s$ times the distance in $G$. We study in this paper spanners that approximate short cycles, and more generally $p$ edge-disjoint paths with $p>1$, between any pair of vertices. For every unweighted graph $G$, we construct a $2$-multipath $3$-spanner of $O(n^3/2)$ edges. In other words, for any two vertices $u,v$ of $G$, the length of the shortest cycle (with no edge replication) traversing $u,v$ in the spanner is at most thrice the length of the shortest one in $G$. This construction is shown to be optimal in term of stretch and of size. In a second construction, we produce a $2$-multipath $(2,8)$-spanner of $O(n^3/2)$ edges, i.e., the length of the shortest cycle traversing any two vertices have length at most twice the shortest length in $G$ plus eight. For arbitrary $p$, we observe that, for each integer $k\ge 1$, every weighted graph has a $p$-multipath $p(2k-1)$-spanner with $O(p n^1+1/k)$ edges, leaving open the question whether, with similar size, the stretch of the spanner can be reduced to $2k-1$ for all $p>1$.
Fichier principal
Vignette du fichier
sirocco10multipath.pdf (245.53 Ko) Télécharger le fichier
Origin : Files produced by the author(s)

Dates and versions

inria-00547869 , version 1 (17-12-2010)



Cyril Gavoille, Quentin Godfroy, Laurent Viennot. Multipath Spanners. Structural Information and Communication Complexity, 17th International Colloquium (SIROCCO), Jun 2010, Sirince, Turkey. pp.211-223, ⟨10.1007/978-3-642-13284-1_17⟩. ⟨inria-00547869⟩
211 View
164 Download



Gmail Facebook X LinkedIn More