Efficient Algorithms and Routing Protocols for Handling Transient Single Node Failures

TL;DR

This paper introduces efficient algorithms and protocols for quickly routing around transient single node failures in large networks, avoiding costly global recomputations and maintaining near-optimal paths.

Contribution

The authors develop faster algorithms for transient failure handling that outperform existing protocols while maintaining comparable path quality.

Findings

Algorithms are an order of magnitude faster than previous methods.

Paths are within 15% of optimal in simulated networks.

Proposed solutions outperform existing protocols in speed and efficiency.

Abstract

Single node failures represent more than 85% of all node failures in the today's large communication networks such as the Internet. Also, these node failures are usually transient. Consequently, having the routing paths globally recomputed does not pay off since the failed nodes recover fairly quickly, and the recomputed routing paths need to be discarded. Instead, we develop algorithms and protocols for dealing with such transient single node failures by suppressing the failure (instead of advertising it across the network), and routing messages to the destination via alternate paths that do not use the failed node. We compare our solution to that of Ref. [11] wherein the authors have presented a "Failure Insensitive Routing" protocol as a proactive recovery scheme for handling transient node failures. We show that our algorithms are faster by an order of magnitude while our paths are equally good. We show via simulation results that our paths are usually within 15% of the optimal for randomly generated graph with 100-1000 nodes.