PSO: Preventive Start-Time Optimization of OSPF Link Weights to Counter Network Failure

This letter proposes a scheme, named Preventive Start-time Optimization (PSO), that determines a suitable set of OSPF link weights at the start time that can handle any link failure scenario preventively. The set of link weights determined by PSO minimizes the worst-case network congestion ratio for all possible link failure scenarios. Numerical results via simulations show that PSO relaxes the worst-case network congestion compared to a conventional scheme that optimizes a set of link weights without considering any link failure at the start time, while PSO avoids the network instability due to the run-time changes of re-optimized link weights whenever a link failure occurs.