Improving the Resilience of Fast Failover Routing: TREE (Tree Routing to Extend Edge disjoint paths)

TL;DR

This paper introduces TREE, a tree routing approach that enhances fast reroute mechanisms in networks by leveraging path diversity, significantly improving resilience while maintaining efficient path lengths.

Contribution

It proposes novel tree-based fast reroute mechanisms that extend edge disjoint paths, improving network resilience by up to 25%.

Findings

Resilience improved by up to 25% on various topologies.

Tree mechanisms retain good path length qualities.

Enhanced fast reroute performance in real-world and synthetic networks.

Abstract

Today's communication networks have stringent availability requirements and hence need to rapidly restore connectivity after failures. Modern networks thus implement various forms of fast reroute mechanisms in the data plane, to bridge the gap to slow global control plane convergence. State-of-the-art fast reroute commonly relies on disjoint route structures, to offer multiple independent paths to the destination. We propose to leverage the network's path diversity to extend edge disjoint path mechanisms to tree routing, in order to improve the performance of fast rerouting. We present two such tree-mechanisms in detail and show that they boost resilience by up to 12% and 25% respectively on real-world, synthetic, and data center topologies, while still retaining good path length qualities.