Cyber Security of Digital Substations: Cyber Threats Identification and Mitigation Evaluation

The digitalization of electrical substations brings advanced monitoring and control capabilities but also amplifies the risk and impact of cyber attacks targeting Operational Technology (OT) systems. This paper emphasizes the need for a comprehensive cyber security assessment in substations, rooted in principles of context-specific protection, defense-in-depth, and pragmatic expectations around attainable security. The outdated notion that OT networks are naturally insulated from cyber threats is refuted, given the expanded attack surface arising from remote access, increased connectivity, and operational flexibility requirements. A particular focus is placed on vulnerabilities in IEC 61850-based substation communication protocols, which lack robust authentication and encryption, making…