A Multi-Level Quantum-Resistant Authentication Framework for Next-Generation Power Systems

The advent of large-scale quantum computing poses critical threats to classical public-key cryptography, raising urgent concerns for mission-critical infrastructures such as power systems. Existing authentication mechanisms—whether based on physical unclonable functions (PUFs), quantum key distribution (QKD), or post-quantum cryptography (PQC)—each offer unique advantages but also face limitations when deployed in isolation. This paper presents a multi-level quantum-resistant authentication methodology that systematically integrates PUF-based device identity, QKD-derived symmetric keys, and PQC-based primitives. To unify these heterogeneous sources, we design a structured session key fusion mechanism that incorporates entropy preprocessing, cross-layer validation tokens, forward-linked context binding, and dual key derivation functions (KDFs). The resulting session key is inseparably derived from all layers, eliminating single points of failure and enhancing defense against both classical and quantum adversaries. Compared with prior single-layer or loosely coupled approaches, the proposed design achieves defense-in-depth, practical scalability across edge and backbone infrastructures, and alignment with emerging cryptographic standards, providing a secure pathway for next-generation power communication systems.