Zero Trust Architecture for Smart Factories: Securing Digital Twins and Cyber-Physical OT Systems

Authors

  • Vignesh Alagappan Senior Member, IEEE, Rheem Manufacturing, Roswell, Georgia, USA. Author

DOI:

https://doi.org/10.63282/3050-9262.IJAIDSML-V7I2P109

Keywords:

Zero Trust Architecture, Smart Factory Security, Digital Twin Integrity, OT-IT Convergence, IEC 62443, Hardware Root of Trust, Device Identity, PKI, Post-Quantum Cryptography, Matter DAC, MITRE ATT&CK for ICS, Brownfield Deployment, Cyber-Physical Systems, Anomaly Detection

Abstract

The rapid digitization of manufacturing environments has produced highly interconnected cyber-physical ecosystems in which traditional security boundaries no longer hold. Operational Technology (OT) networks once isolated by design now interface with enterprise IT systems, cloud platforms, and AI-driven analytics engines, creating an expanded and heterogeneous attack surface. Perimeter-centric security models, which assume implicit trust within network boundaries, are structurally incapable of addressing this complexity. This paper proposes a comprehensive Zero Trust Architecture (ZTA) tailored for smart factory environments. Five principal contributions are made: (1) an identity-centric trust model anchored in hardware roots of trust and cryptographic device attestation using TPM 2.0 and X.509 certificates, with a PAA-PAI-DAC hierarchy aligned to the CSA Matter specification, and post-quantum cryptographic agility implemented via NIST FIPS 203/204/205; (2) a trust-aware data pipeline that enforces continuous verification at every telemetry stage from field device to cloud analytics and digital twin state; (3) a safety-security co-design framework that reconciles Zero Trust enforcement with the availability and determinism requirements of industrial control systems; (4) a structured threat scenario evaluation anchored to MITRE ATT&CK for ICS techniques T0856, T0859, T0867, and T0862; and (5) a compliance alignment mapping between ZTA principles and IEC 62443 security levels and NIST CSF 2.0 functions. Results demonstrate that identity-centric Zero Trust enforcement significantly reduces the exploitable attack surface while preserving operational continuity in brownfield environments.

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Published

2026-04-15

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Section

Articles

How to Cite

1.
Alagappan V. Zero Trust Architecture for Smart Factories: Securing Digital Twins and Cyber-Physical OT Systems. IJAIDSML [Internet]. 2026 Apr. 15 [cited 2026 Apr. 23];7(2):50-64. Available from: https://ijaidsml.org/index.php/ijaidsml/article/view/550