OSPF Weight Setting Optimization for Single Link Failures

TL;DR

This paper addresses optimizing OSPF link weights to maintain efficient routing during single link failures, using heuristic algorithms to improve network resilience and performance.

Contribution

It introduces two heuristic strategies based on Tabu Search for optimal OSPF weight setting in failure scenarios, enhancing network robustness.

Findings

Both heuristics effectively optimize link weights for failure states.

The heuristics outperform traditional methods in maintaining routing efficiency.

Comparison shows trade-offs between the two strategies.

Abstract

In operational networks, nodes are connected via multiple links for load sharing and redundancy. This is done to make sure that a failure of a link does not disconnect or isolate some parts of the network. However, link failures have an effect on routing, as the routers find alternate paths for the traffic originally flowing through the link which has failed. This effect is severe in case of failure of a critical link in the network, such as backbone links or the links carrying higher traffic loads. When routing is done using the Open Shortest Path First (OSPF) routing protocol, the original weight selection for the normal state topology may not be as efficient for the failure state. In this paper, we investigate the single link failure issue with an objective to find a weight setting which results in efficient routing in normal and failure states. We engineer Tabu Search Iterative heuristic using two different implementation strategies to solve the OSPF weight setting problem for link failure scenarios. We evaluate these heuristics and show through experimental results that both heuristics efficiently handle weight setting for the failure state. A comparison of both strategies is also presented.