Governments have strongly recognized that critical infrastructures (CIs) play crucial roles in underpinning economy, security and societal welfare of countries. The proper functioning of energy, transportation, water plants, telecommunication, financial and other services, is vital for all communities. If a failed infrastructure is unable to deliver services and products to the others, damages may easily cascade into the larger system of interdependent CIs. Understanding such complex system-of-systems dynamics would help to prevent networked CIs from potential catastrophic cascading effects. However, existing security measures to protect a CI from threats and cyberattacks do not usually cross the organization’s boundaries. This research proposes a block building modeling approach based on System Dynamics (SD) to improve the understanding of dynamics of disruptive events in interdependent CI systems. Unlike most of the previous works in modeling and simulation of interdependent CIs, this novel approach accounts for both dynamics within a CI and across CIs while investigating two relevant dimensions of system resilience: operational state and service level. Blocks of models are iteratively developed and assembled together to generate complex scenarios of disruption with the final purpose of simulation-based impact analysis, resilience assessment, policy and risk scenario evaluation. The dynamic interdependency models offer a valuable and flexible tool for predictive analysis to support risk managers in assessing scenario of crisis as well as CI operators towards more effective investment decisions and collective response actions. Principles of epidemic modeling are used to replicate diffusion and recovery dynamics of CI operations. Hence, SD is combined with a game-theoretic approach to understand “cyber-epidemics” triggered by strategic interactions between attacker and defender. Cyber attack-defense dynamics are modeled as a continuous game of timing to highlight that effectiveness of strategic moves strongly depends on “when to act”. The game-theoretic model is applied for the optimization of proactive and reactive defense scenarios. This application demonstrates how the dynamic interdependency models can be used to support strategic cybersecurity decisions within organizations. Promoting the use of information sharing to improve cybersecurity across organizations, a further application of the dynamic interdependency model represents a relevant contribution to the design of a cyber incident early warning system for CI operators. In accordance with guidelines issued by the European Union Agency for Network and Information Security (ENISA) to identify critical assets and services, the modeling is extended by a perspective of CI operators to demonstrate how it can be used to gain situational awareness in the context of European CIs.    «

Governments have strongly recognized that critical infrastructures (CIs) play crucial roles in underpinning economy, security and societal welfare of countries. The proper functioning of energy, transportation, water plants, telecommunication, financial and other services, is vital for all communities. If a failed infrastructure is unable to deliver services and products to the others, damages may easily cascade into the larger system of interdependent CIs. Understanding such complex system-of-s...    »