Optical networks are vulnerable to failures due to targeted attacks or large-scale disasters. The recoverability of optical networks refers to the ability of an optical network to return to a desired performance level after suffering topological perturbations such as link failures. This paper proposes a general topological approach and recoverability indicators to measure the network recoverability for optical networks for two recovery scenarios: 1) only the links which are damaged in the failure process can be recovered and 2) links can be established between any pair of nodes that have no link between them after the failure process. We use the robustness envelopes of realizations and the histograms of two recoverability indicators to illustrate the impact of the random failure and recovery processes on the network performance. By applying the average two-terminal reliability and the network efficiency as robustness metrics, we employ the proposed approach to assess 20 real-world optical networks. Numerical results validate that the network recoverability is coupled to the network topology, the robustness metric and the recovery strategy. We further show that a greedy recovery strategy could provide a near-optimal recovery performance for the robustness metrics. We investigate the sensitivity of network recoverability and find that the sensitivity of the recoverability indicators varies according to different robustness metrics and scenarios. We also find that assortativity has the strongest correlation with both recoverability indicators.

由于有针对性的攻击或大规模灾难，光网络很容易出现故障。光网络的可恢复性是指光网络在遭受诸如链路故障之类的拓扑扰动后恢复到所需性能水平的能力。本文提出了一种通用的拓扑方法和可恢复性指标来衡量光网络在两种恢复情况下的网络可恢复性：1）仅可以恢复在故障过程中受损的链路，并且2）可以在任意一对节点之间建立链路在失败过程之后，它们之间没有链接。我们使用实现的鲁棒性信封和两个可恢复性指标的直方图来说明随机故障和恢复过程对网络性能的影响。通过将平均两个终端的可靠性和网络效率用作鲁棒性指标，我们采用了所提出的方法来评估20个现实世界的光网络。数值结果验证了网络的可恢复性已与网络拓扑，鲁棒性指标和恢复策略耦合在一起。我们进一步表明，贪婪的恢复策略可以为健壮性指标提供接近最佳的恢复性能。我们调查了网络可恢复性的敏感性，发现可恢复性指标的敏感性根据不同的鲁棒性指标和方案而有所不同。我们还发现，分类性与两个可恢复性指标之间具有最强的相关性。我们采用建议的方法评估20个现实世界的光网络。数值结果验证了网络的可恢复性已与网络拓扑，鲁棒性指标和恢复策略耦合在一起。我们进一步表明，贪婪的恢复策略可以为健壮性指标提供接近最佳的恢复性能。我们调查了网络可恢复性的敏感性，发现可恢复性指标的敏感性根据不同的鲁棒性指标和方案而有所不同。我们还发现，分类性与两个可恢复性指标之间具有最强的相关性。我们采用建议的方法评估20个现实世界的光网络。数值结果验证了网络的可恢复性已与网络拓扑，鲁棒性指标和恢复策略耦合在一起。我们进一步表明，贪婪的恢复策略可以为健壮性指标提供接近最佳的恢复性能。我们调查了网络可恢复性的敏感性，发现可恢复性指标的敏感性根据不同的鲁棒性指标和方案而有所不同。我们还发现，分类性与两个可恢复性指标之间具有最强的相关性。我们进一步表明，贪婪的恢复策略可以为健壮性指标提供接近最佳的恢复性能。我们调查了网络可恢复性的敏感性，发现可恢复性指标的敏感性根据不同的鲁棒性指标和方案而有所不同。我们还发现，分类性与两个可恢复性指标之间具有最强的相关性。我们进一步表明，贪婪的恢复策略可以为健壮性指标提供接近最佳的恢复性能。我们调查了网络可恢复性的敏感性，发现可恢复性指标的敏感性根据不同的鲁棒性指标和方案而有所不同。我们还发现，分类性与两个可恢复性指标之间具有最强的相关性。