System Performance Metrics of Complex Networks: Resilience vs. Availability

This paper defines networks as systems that capture information about the interactions among different system parts. For instance, networks can be used describe infrastructure like the internet, roadways, and railroads. However, these networks are susceptible to service disruptions or retardation due to various factors, including natural hazards, aging, accidents, or intentional causes. Networks need to be available and resilient to ensure their effectiveness and reliability. Operational availability denotes uninterrupted or downtime-free access to a system, service, or application. Resilience refers to a system's ability to recover from unexpected events or disruptions and continue functioning as intended. Although these two concepts are related, they have distinct differences that are critical to consider when making decisions about system design, maintenance, and risk management. The significance of operational availability and resilience across various domains, such as technology, transportation, healthcare, and military operations, have advantages and disadvantages. This paper aims to compare the operational availability and resilience of networks.