Post Quantum Migration for OT Security: An Exploratory Study in PQ-PUFbased Device Authentication for CPS & IoT

The possible risk of Quantum attacks on the communication security of Cyber Physical Systems (CPS) and Internet of Things (IoT) emphasizes the necessity for proactive actions. The ongoing efforts of the US National Institute of Standards and Technology (NIST) to standardize quantum-resistant algorithms play a vital role in integrating security measures. Our research delves into the practical implications of migrating to Post-Quantum (PQ) algorithms in authentication schemes. We propose a novel Physical Unclonable Functions (PUF) based device authentication mechanism with the adoption of PQ algorithms to perform sensitive interactions in real-time. Moreover, we focus on resource-constrained implementation and performance analysis of quantum algorithms for achieving crypto agility. The results provide insight into the real-world use of NIST PQ algorithms and highlight the temporal complexities of key pair generation, encryption and decryption processes with the integration of PUF based device authentication measures. We have identified that in our proposed PQ-PUF based authentication scheme, DILITHIUM5 with SHA3-512 has performed significantly better than RSA1024 with SHA2-256 during the stages of central registration and verification. The results also shed light on the sizes of plaintext, ciphertext, and public and private keys, which will be important factors in resource-constrained implementations.