Opportunistic resilience embedding (ORE): Toward cost-efficient resilient virtual networks

Previous work protects virtual networks by setting aside backup resources. Although effective, this kind of solution tends to be expensive, as backup resources increase the cost to infrastructure providers and usually remain idle. This paper presents ORE (opportunistic resilience embedding), a novel embedding approach for protecting virtual links against substrate network disruptions. ORE's design is two-fold: while a proactive strategy embeds each virtual link into multiple substrate paths in order to mitigate the initial impact of a disruption, a reactive one attempts to recover any capacity affected by an underlying disruption. Both strategies are modeled as optimization problems. Additionally, since the embedding problem is NP-Hard, ORE uses a simulated annealing-based meta-heuristic to solve it efficiently. Numerical results show that ORE can provide resilience to disruptions at a lower cost.