Model-based Evaluation of the Resilience of Critical Infrastructures under Cyber Attacks

In this paper we report recent results on modelling the impact of cy-ber-attacks on the resilience of complex industrial systems. We use a hybrid model of the system under study in which the accidental failures and the mali-cious behaviour of the Adversary are modelled stochastically, while the conse-quences of failures and attacks are modelled in detail using deterministic mod-els. This modelling approach is demonstrated on a complex case study - a refer-ence power transmission network (NORDIC 32), enhanced with a detailed model of the computer and communication network used for monitoring, pro-tection and control compliant with the international standard IEC 61850. We studied the resilience of the modelled system under different scenarios: i) a base-line scenario in which the modelled system operates in the presence of ac-cidental failures without cyber-attacks; ii) several different scenarios of cyber-attacks. We discuss the usefulness of the modelling approach, of the findings, and outline directions for further work