A Preliminary Ontology for 5G Network Resilience: Hybrid Threats, Risk Reduction, Compliance

The security of 5G networks, a critical infrastructure across Europe, is paramount, especially along the EU’s transport corridors, given the rise of hybrid threats. This paper presents a preliminary ontology for 5G network security, modelling and mitigating these threats while ensuring compliance with European Commission cybersecurity requirements. The ontology, grounded in the ENISA 5G Threat Landscape and ISO 27005 risk management standards, integrates key concepts—assets, threats, risks, and mitigation strategies—to enable systematic risk reduction. Iterative validation, employing SHACL constraints and logical reasoning (Protégé’s HermiT reasoner), demonstrates the ontology’s adaptability to emerging risks, including attacks on NG-RAN, SDN, and cloud-based infrastructure, and its support for Connecting Europe Facility (CEF) mandates (viz., high-risk supplier management, achievement of 5G network supply chain resilience and strategic autonomy, empowerment of network operators, and data security). This work establishes a foundation for deploying scalable, resilient, and adaptable 5G systems by bridging conceptual modelling and real-world compliance. Future work will validate the ontology’s performance in testbeds with industry partners under real-world conditions.