Cyber Resilience Framework for Industrial Control Systems: Concepts, Metrics, and Insights

In this paper, we have analyzed the resilience property of industrial control systems (ICS) in the events of cyberattacks using subjective approach. We are proposing a comprehensive cyber resilience framework for the ICS by decomposing the resilience metric into a hierarchy of several sub-metrics. These metrics form a tree structure that has the potential to capture qualitative information about system's security and resilience posture and can be used as a high-level framework to identify where modeling and analysis are needed to be carried out. We present a brief description of resilient ICS characteristics and a cyber resilience assessment model for ICS. Finally, we present the cyber resilience metrics formulation methods and an illustration of resilience metrics calculation using Analytical Hierarchy Process (AHP). Our resilience framework can serve as a platform for a multi-criteria decision aid and help technical experts in identifying the gap in the study of ICS resilience.