Securing critical infrastructures with a cybersecurity digital twin

With the diffusion of integrated design environments and tools for visual threat modeling for critical infrastructures, the concept of Digital Twin (DT) is gaining momentum in the field of cybersecurity. Its main use is for enabling attack simulations and evaluation of countermeasures, without causing outage of the physical system. However, the use of a DT is considered foremost as a facilitator of system operation rather than an integral part of its architecture design. In this work, we introduce a specific architecture view in the system representation, called Cybersecurity View. From it, we derive a cybersecurity Digital Twin as part of the security-by-design practice for Industrial Automation and Control Systems used in Critical Infrastructures. Not only this digital twin serves the purpose of simulating cyber-attacks and devising countermeasures, but its design and function are also directly tied to the architecture model of the system for which the cybersecurity requirements are posed. Moreover, this holds regardless of whether the model is generated as part of the development cycle or through an empirical observation of the system as-is. With this, we enable the identification of adequate cybersecurity measures for the system, while improving the overall system design. To demonstrate the practical usefulness of the proposed methodology, its application is illustrated through two real-world use cases: the Cooperative Intelligent Transport System (C-ITS) and the Road tunnel scenario.