An Operator-Driven Approach for Modeling Interdependencies in Critical Infrastructures Based on Critical Services and Sectors

To trigger disruptive cascading effects among Critical Infrastructures (CIs), advanced cyber attacks take advantage of dependences among organizations. CIs are highly interconnected due to services and products they deliver one another to guarantee correct operational processes in such complex system-of-systems. Consequently, proper countermeasures in case of threats to CIs must consider interdependencies between them. The strategic use of information systems to coordinate response efforts of CI operators at national and international levels is a major objective towards more resilient societies. As relevant contribution to the development of a cyber incident early warning system for CI operators, this paper presents a System Dynamics (SD) interdependency model based on critical services that different operators must provide to guarantee the correct functioning of a CI. We explain model requirements and characteristics, and demonstrate how it can be used to gain situational awareness in the context of European CIs.