Physical unclonable functions and dynamic partial reconfiguration for security in resource-constrained embedded systems

Authentication and encryption within an embedded system environment using cameras, sensors, thermostats, autonomous vehicles, medical implants, RFID, etc. is becoming increasing important with ubiquitious wireless connectivity. Hardware-based authentication and encryption offer several advantages in these types of resource-constrained applications, including smaller footprints and lower energy consumption. Bitstring and key generation implemented with Physical Unclonable Functions or PUFs can further reduce resource utilization for authentication and encryption operations and reduce overall system cost by eliminating on-chip non-volatile-memory (NVM). In this paper, we propose a dynamic partial reconfiguration (DPR) strategy for implementing both authentication and encryption using a PUF for bitstring and key generation on FPGAs as a means of optimizing the utilization of the limited area resources. We show that the time and energy penalties associated with DPR are small in modern SoC-based architectures, such as the Xilinx Zynq SoC, and therefore, the overall approach is very attractive for emerging resource-constrained IoT applications.