Path Splicing with Guaranteed Fault Tolerance

This paper addresses the problem of exploring the fault tolerance potential of the routing primitive called path splicing. This routing mechanism has been recently introduced in order to improve the reliability level of networks. The idea is to provide for each destination node in a network several different routing trees, called slices, by running different routing protocols simultaneously. The possibility for the traffic to switch between different slices at any hop on the way to the destination makes it possible to achieve a level of reliability that is close to the ideal level achieved by the underlying network. In this work we show that there is a method for computing just two slices that achieves fault tolerance against all single-link failures that do not disconnect the underlying network. We present an experimental evaluation of our approach, showing that for a number of realistic topologies our method of computing the slices achieves the same level of fault tolerance that is achieved by a much larger number of slices using the previously proposed method.