Solar Cell Based Physically Unclonable Function for Cybersecurity in IoT Devices

Abstract

Internet of Things (IoT) devices are mostly small and operate wirelessly on limited battery supply, and therefore have stringent constraints on power consumption and hardware resources. Therefore, energy-efficient (low energy) design is paramount for the successful deployment of resource constrained IoT devices. Further, Physical Unclonable Functions (PUFs) have evolved as a popular hardware security primitive for low cost, mass produced IoT devices with very constrained resources. Energy harvesting technologies utilizing solar cells are being used in ultra-low power IoT devices to satisfy the energy requirement. In this paper, we utilize the intrinsic variations in solar cells to design a novel solar cell based PUF. As a proof of concept, we have used the Tiva TM4C123GH6PM microcontroller to build our solar cell based PUF. From our experiments, we found that the proposed solar cell based PUF has the uniformity value of 49.21% which is close to the ideal value of 50%. Further, the proposed solar cell based PUF has worst case reliabilities of 92.97% and 90.62% with variations in temperature and light intensity, respectively.