PUF Implementation and Application for Securing IoT Devices

Abstract

In this paper, to defend against threats of bitstream decoding, bitstream spoofing, reverse engineering, and hijacking the system, we encrypt the bitstream to enhance the security of FPGA (Field Programmable Gate Array) based IoT (Internet of Things) devices. IoT refers to the phenomenon of the ever-growing network of physical objects (Things) that have the capability for internet connectivity, data collection, and information exchange that occurs between these objects and other Internet-enabled devices and systems. FPGAs can enable vastly growing IoT applications since they can interface with the outside world easily with low power, low latency, high determinism with reprogrammable and re-configurable capabilities. To defend against threats and attacks to FPGA designs, we encrypt the bitstream that configures FPGA. In order to produce a completely unique key for encryption, a physical unclonable function (PUF) is implemented on Altera DE2-115 board. Such an implementation leverages the intrinsic physical characteristics of the FPGA in order to generate a more secure, reliable, and unclonable encryption key. The key generation has been tested on multiple Altera DE2-115 FPGA boards to validate the uniqueness of the key. We then apply the unclonable key to encrypt bitstream to program a Xilinx Zynq-7000 FPGA based IoT device to enhance the security of the IoT device.