A Distributed Algorithm for Finding All Best Swap Edges Of a Minimum Diameter Spanning Tree*

COMPUTER SCIENCE AND ENGINEERING

Communication in networks suffers if a link fails. When the links are edge of a tree that has been chosen from an underlying graph of all possible links, a broken link even disconnect the network. Most often, the link is restored quickly. A good policy to deal with this sort of transient link failures is swap rerouting s, where the temporarily broken link is replaced by a single swap link from the underlying graphs. A rapid replacement of a broken link by a swap link is only possible if all swap links have been precomputed. Then the selection of high quality swap links is essential; it must follow the same objective as the originally chosen communication subnetwork. We are interested in a minimum diameter tree in a graph with edge weights (so as to minimize the maximum travel time of messages). Hence, each swap link must minimize (among all possible swaps) the diameter of the tree that results from swapping. We advice a distributed algorithm that efficiently computes all of these swap links and we explain, how to route message across swap edges with a compact routing scheme. lastly, we consider the computation of swap edges in an arbitrary spanning tree, where swap edges are chosen to reduce the time required to adapt routing in case of a failures, and give efficient distributed algorithms for two variants of this problem.

This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.