Enhanced ID Authentication Scheme Using FPGA-Based Ring Oscillator PUF

FPGA-based ring oscillator (RO) PUF is very popular for its unique properties and easy implementation. However, the designs are normally expensive, and the RO frequency is highly sensitive to operating condition and other types of global variations. In addition, the local variations are also highly correlated, which normally requires complex the identification (ID) extraction algorithm and/or a large number of ROs. In this work, by using statistical analysis, we have experimentally shown that the RO frequencies are very sensitive to global variation factors. Fortunately, their local process variations within a die are relatively consistent regardless of the operating condition and this can be used for unique ID extraction. Furthermore, we have proposed an ID authentication scheme using FPGA-based RO PUF. Our proposed scheme allows to fully extract the local variation characteristics by using an almost technology-and vendor-agnostic PUF circuit. In addition, the ID extraction circuit is kept simple and compact, so that the overall design is area-and energy-efficient. The experimental results show a very good level of reliability (99.94 %) for a design of 32 ROs in different physical FPGAs.