Distance labeling schemes are schemes that label the vertices of a graph with short labels in such a way that the distance between any two vertices u and v can be determined efficiently (e.g., in constant or logarithmic time) by merely inspecting the labels of u and v, without using any other information. Similarly, routing labeling schemes are schemes that label the vertices of a graph with short labels in such a way that given the label of a source vertex and the label of a destination, it is possible to compute efficiently (e.g., in constant or logarithmic time) the port number of the edge from the source that heads in the direction of the destination. In this paper we show that the three major classes of nonpositively curved plane graphs enjoy such distance and routing labeling schemes using O(log2 n) bit labels on n-vertex graphs. In constructing these labeling schemes interesting metric properties of those graphs are employed.
Victor Chepoi, Feodor F. Dragan, Yann Vaxès