MULTI-SOURCE SPANNING TREE PROBLEMS

Abstract

We consider a model of multicast communication in a network whereby multiple sources have messages to disseminate among all sites of a network. We propose that the messages from all sources are disseminated along the same spanning tree of the network and consider the problem of constructing an optimal such tree. One measure for suitability of the construction is the sum of distances from all sources to all other vertices. We show that finding the exact solution in this case in [Formula: see text]-hard (in the strong sense). We then investigate solutions for some restricted classes of graphs and give efficient algorithms for those. We also consider an alternative measure of goodness for the spanning tree, being the maximum eccentricity of a source. We show that the problem of finding such a minimum eccentricity spanning tree is somewhat easier to solve and give a pseudo-polynomial solution algorithm.