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arXiv · 1202.4160

Interval Routing Schemes for Circular-Arc Graphs

Frank Gurski·Patrick Gwydion Poullie
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Abstract

Interval routing is a space efficient method to realize a distributed routing function. In this paper we show that every circular-arc graph allows a shortest path strict 2-interval routing scheme, i.e., by introducing a global order on the vertices and assigning at most two (strict) intervals in this order to the ends of every edge allows to depict a routing function that implies exclusively shortest paths. Since circular-arc graphs do not allow shortest path 1-interval routing schemes in general, the result implies that the class of circular-arc graphs has strict compactness 2, which was a hitherto open question. Additionally, we show that the constructed 2-interval routing scheme is a 1-interval routing scheme with at most one additional interval assigned at each vertex and we an outline algorithm to calculate the routing scheme for circular-arc graphs in O(n^2) time, where n is the number of vertices.

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Frank Gurski, Patrick Gwydion Poullie. 2012-02-19. Interval Routing Schemes for Circular-Arc Graphs. https://arxiv.org/abs/1202.4160

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