On the Reliability of the Ring Oscillator Physically Unclonable Functions

Abstract

In this paper we study the reliability of ring oscillator PUFs. We correlate the reliability with the distance between the measured oscillation frequencies, for different operating conditions. We propose a reliability evaluation metric based on differential frequency threshold, which allows the design of a robust PUF. In addition, we evaluate the characteristics of the resulting PUF and we devise a scenario for guaranteeing the overall reliability by selecting appropriate error correcting codes.