Cyber-physical security using system-level PUFs

Cyber Physical Systems (CPS) is an emerging computing paradigm that is becoming prevalent in various technologies. Achieving a trustworthy CPS requires us to build mechanisms that ensure the integrity and authenticity of these systems. Fortunately with the new advancements in semi-conductor-based technologies, in particular Physical Unclonable Functions (PUFs), we have the potential to build secure couplings between cyber and physical substrates based on intrinsic physical material. In this paper, we share some thoughts on how to utilize the PUF technology for security in CPS. Based on a composition approach, we illustrate the benefits of combining multiple PUF elements, with some inherently bias factor, into one randomly secure and strong system-level PUF.