Show simple item record

dc.contributor.authorSlivkins, Aleksandrsen_US
dc.contributor.authorPal, Martinen_US
dc.description.abstractDisjoint Paths is the problem of finding paths between given pairs of terminals in a graph such that no vertices are shared between paths. We analyze fixed-parameter tractability of several new Disjoint Paths-like routing problems motivated by congestion control in computer networks. In one model we are interested in finding paths between $k$ pairs of terminals such that the first edge of each path is not shared with any other path. We prove that this problem is fixed-parameter tractable on directed graphs, in contrast to Disjoint Paths that are known to be NP-hard even for $k=2$. We improve our algorithm for two special cases: when the graph is acyclic and when all sources lie in distinct nodes. We consider extensions: a second-node-disjoint analog and a slightly generalized version of SAT. Another model, bottleneck-edge-disjoint paths, is a generalization of Disjoint Paths. For directed acyclic graphs, we show that bottleneck-edge-disjoint paths is $W[1]$-hard and hence unlikely to be fixed-parameter tractable. We give an algorithm that runs in time $n^{O(k)}$. These two results easily extend to Unsplittable Flows.en_US
dc.format.extent618165 bytes
dc.publisherCornell Universityen_US
dc.subjectcomputer scienceen_US
dc.subjecttechnical reporten_US
dc.titleOn Fixed-Parameter Tractability of Some Routing Problemsen_US
dc.typetechnical reporten_US

Files in this item


This item appears in the following Collection(s)

Show simple item record