Novel Physical Unclonable Function Implementation for Microcontrollers and Field Programmable Gate Arrays

Physical Unclonable Functions (PUFs) are frequently exploited for security purposes. In particular, they are adopted to generate unique authentication passwords and cryptographic keys, with no need to store any secret information in non-volatile memories that can be easily attacked. In this paper, we present a novel PUF based structure, that can be implemented at low costs in microcontrollers and FPGAs, by exploiting the circuitry that is already present in their General Purpose Input-Output (GPIO) interface. The proposed PUF based scheme has been implemented on five different FPGA devices, in order to experimentally verify their correct operation under various realistic operating conditions. We will show that our proposed PUF based structure features a good uniqueness (of the 49.75%), a uniformity close to the ideal value of the 50%, an average steadiness of the 99.33%, and a maximum reliability of the 99.61%, for a temperature ranging from 5°C to 65°C.