A dependable and resource-frugal ring oscillator physically unclonable function

ABSTRACT

Silicon Physical Unclonable Function (PUF) is a crucial component for hardware security, providing unique device identification in networks. PUF provides robust security for cryptographic keys and IC digital fingerprints. However, resource constraints in network devices limit its use in security protocols. To address this challenge, PUF offers a lightweight hardware security solution with two main types: strong PUF (e.g. arbiter PUF) and Ring Oscillator (RO) PUF. The first option produces large CRPs with improved security but incurs hardware overhead, whereas the second option offers lower overhead with smaller CRP size, leading to reduced security. This paper introduces a novel, cost-effective solution to enhance RO PUF security while reducing hardware limitations. Our proposal involves a resource sharing technique with scan flip-flops, multiplexers, and inverter logic. This approach takes advantage of existing scan chains in circuit netlists to reduce PUF area without sacrificing uniqueness. A specific set of test patterns and odd number of inverters transform the memory-based PUF into an RO PUF. Our solution also leverages pass transistor-based implementation to significantly reduce power consumption and area overhead. Simulation results show that our approach effectively reduces area and power consumption while maintaining PUF uniqueness.

KEYWORDS:

• Physical Unclonable Function (PUF)
• Scan flip-flop
• Hardware security
• Challenge response pairs (CRPs)
• Ring Oscillator (RO)

Disclosure statement

No potential conflict of interest was reported by the author(s).