A Physically Unclonable Function for Biomedical Devices Authentication

Security and authentication of low-power embedded systems for the internet of things (IoT) is a research topic that is growing due to the extensive numbers of devices. Modern biomedical devices configured and calibrated wirelessly are very specific embedded systems with limited power and processing capacity, but with security challenges requiring low-power and robust security. This paper presents a review of security solutions based on Physical Unclonable Functions (PUF) for medical devices and the major hardware challenges to design a robust PUF. We discuss modern hardware solutions for weak and strong PUFs and how they are implemented in modern CMOS technology. Three PUFs with entropy sources based on relaxation oscillators and ring oscillators (ROPUFs), implemented in 130 nm CMOS technology are presented. The proposed self-biased RO improved the sensitivity to PV variations. The coupled relaxation oscillator obtained a power consumption of 10.56 mW. Additionally, we discuss how the process, supply voltage, and temperature (PVT) variations affect the PUF performance.