FEASIBILITY OF CRYPTOGRAPHY IN A BLOCKCHAIN-ENHANCED ICS SECURITY

Kazi Mohammed Amanat Kamal, Rafiqul Islam, Azizur Rahman

Keywords: Blockchain ICS SCADA SECURITY Homomorphic Encryption

TL;DR: Testing Feasibility of Cryptography for end to end holistic security of data in ICS

Abstract: The convergence of Information Technology (IT) and Operational Technology (OT) has exposed critical industrial control loops to cyber threats, necessitating advanced cryptographic defenses. While recent literature heavily advocates for "hybrid" architectures combining blockchain and homomorphic encryption, this paper demonstrates that such approaches are architecturally invalid for the Purdue Model’s physical control layer (Level 0-1). We argue that the probabilistic latency of blockchain consensus and the computational overhead of homomorphic encryption fundamentally violate the deterministic, ≤10 ms response standards required for safety-critical systems. By introducing a "Latency Collision Matrix," we quantify this "performance-security paradox," revealing that hybrid models introduce latencies ranging from 51 ms to 440 ms—effectively acting as a denial-of-service condition for real-time controllers. This paper proposes a "Resource-Constrained Security Framework" that prioritizes deterministic, lattice-based lightweight cryptography over distributed ledgers for sensor-to-controller communications, ensuring security without compromising the physics of the control process.

Submission Number: 22