Functional Metrics to Evaluate Network Vulnerability to Disasters

Book chapter, 2020

Disasters can cause, intentionally or unintentionally, the failure of several network components at the same time. A vast body of literature focuses on understanding the impact of disasters on the network infrastructure to enable the design of more robust networks. However, these multiple failures also affect the applications running over the network infrastructure. Even when the impact of a disaster on the structural performance indicators is insignificant, the functional implications can be substantial. More importantly, a small degradation in network performance can result in severe disruptions of overlay applications, or even completely prevent their proper functioning. Therefore, it is essential to analyze the impact of a disaster on the functional aspects of the network, i.e. the Quality of Service (QoS) offered to the applications and the Quality of Experience (QoE) perceived by the users. In this chapter, we review the functional metrics for evaluating the impact of disasters on applications and users. We specify relevant packet- and network-based functional metrics as well as perceived subjective metrics, and demonstrate the impact of disasters on QoS and QoE metrics in a case study.