A Hardware-Rooted Blockchain Security Framework for IoT With PUF-Based Authentication

Abstract

The integration of blockchain with the Internet of Things (IoT) can enable decentralized trust, secure data exchange, and tamper-resistant operation in distributed cyber-physical systems. However, the practical deployment of blockchain in resource-constrained IoT nodes remains limited by the high computational and energy cost of conventional Proof-of-Work (PoW) mechanisms and by the security risks associated with persistent cryptographic key storage. This paper presents a hardware–software co-design framework for secure and lightweight IoT blockchain implementation based on the joint use of Physically Unclonable Functions (PUFs) and a reconfigurable FPGA mining architecture. The proposed framework incorporates two FPGA-oriented PUF designs: a multi-mode delay PUF for device authentication in public blockchain settings and a glitch-enhanced memory PUF for secure key generation in private blockchain environments. Experimental evaluation shows that both designs achieve near-ideal uniqueness (above 49.95%) and high reliability (above 99.5%) over a temperature range of $-40^{\circ }\mathrm {C}$ to $80^{\circ }\mathrm {C}$ , while also improving resistance to modeling and physical attacks. To reduce mining overhead, a configurable linear feedback shift register (CLFSR)-based pseudo-random function is introduced as an alternative to conventional cryptographic hashing. Implemented on a Xilinx Artix-7 FPGA, the proposed mining module achieves 3.13 Mhash/s throughput with only 0.12 W power consumption, corresponding to a 93% reduction in power compared with conventional approaches. The CLFSR primitive is positioned as a lightweight pseudo-random mining function for permissioned and resource-constrained IoT blockchains rather than as a drop-in cryptographic-hash replacement for open, high-value public chains, and all reported throughput values (3.13 Mhash/s) correspond to post-place-and-route operation at 100 MHz on the same Artix-7 device. By using PUF-generated responses as hardware-rooted seeds for mining and authentication, the framework removes the need for permanent secret storage and establishes a secure chain from device identity to consensus participation. Experimental results confirm that the proposed architecture provides a favorable trade-off among security, hardware cost, and energy efficiency, making it suitable for practical deployment in industrial IoT, smart infrastructure, and other resource-constrained distributed systems.