Reliable PUF-Based Local Authentication With Self-Correction

Abstract

Physical unclonable functions (PUFs) can extract chip-unique signatures from integrated circuits (ICs) by exploiting the uncontrollable randomness due to manufacturing process variations. These signatures can then be used for many hardware security applications including authentication, anti-counterfeiting, IC metering, signature generation, and obfuscation. However, most of these applications require error correcting methods to produce consistent PUF responses across different environmental conditions. This paper presents a novel method to enable lightweight, secure, and reliable PUF-based authentication. A two-level finite-state machine (FSM) is proposed to correct erroneous bits generated by environmental variations (e.g., temperature, voltage, and aging variations). In the proposed method, each PUF response is mapped to a key during design phase. The actual key can be determined from the PUF response only after the chip is fabricated. Because the key is not known to the foundry, the proposed approach prevents counterfeiting. The performance of the proposed method and other applications are also discussed. Our experimental results show that the cost of the proposed self-correcting two-level FSM is significantly less than that of the commonly used error correcting codes. It is shown that the proposed self-correcting FSM consumes about $2{\boldsymbol \times }$ to $10{\boldsymbol \times }$ less area and about $20{\boldsymbol \times }$ to $100{\boldsymbol \times }$ less power than the Bose–Chaudhuri–Hochquenghem codes.