Quantum-secured distributed measurement systems for critical infrastructures operations

In the context of homeland security, protecting critical infrastructures (CIs) is paramount, given emerging threats that exploit cyber–physical systems and quantum computers. As CIs rely on distributed measurement systems (DMSs), they require stringent security protocols for remote transmission of commands and measurement results. This paper proposes a novel architectural paradigm for DMSs that integrate quantum key distribution (QKD) to ensure information-theoretic security (ITS). Specifically, a hardware-agnostic architecture is introduced to reconcile quantum cryptography with industrial applications, addressing the conceptual and systemic integration of quantum technologies with DMSs. The proposed solution decouples metrological logic from hardware, facilitating a secure interface between QKD layers and measurement nodes. Two key management modalities, client-initiated and server-initiated, are proposed to address diverse operational requirements; the former minimizes latency, while the latter ensures superior synchronization. Experimental validation is provided by leveraging the facilities of a quantum metropolitan area network (QMAN) that is currently under deployment. The characterization reveals that the proposed architecture effectively reconciles the stochastic, low-throughput nature of QKD with DMSs demands. The system demonstrates operational autonomy, maintaining data integrity during QKD outages. Finally, this work establishes a trajectory from hybrid models toward quantum-resistant networks for CIs.