A system for multi-level authentication with physically unclonable functions

Abstract

We analyze deficiencies in existing Physically Unclonable Function (PUF) systems and protocols, and propose a new system of PUFs (SoP) that is numerically secure under extended attacker privileges and attack scenarios. Our proposed system uses a multi-level authentication scheme and employs different designs of PUF to achieve high security with low computational complexity and small footprint. By employing role-specific PUF designs, SoP reduces the area over existing PUF-based authentication solutions by more than 68%. The key principles are: (i) reduce assumptions required to guarantee numerical security to a minimum set of practical assumptions; (ii) combine different PUF types to optimize security while minimizing resource requirements; (iii) provide multiple layers of authentication as a force-multiplier for the trusted party. This multi-level protocol resolves security deficiencies with regard to manin-the-middle attacks and challenge-response-pair (CRP) storage issues in conventional PUF protocols. Furthermore, SoP allows recognition and sealing of security breaches. A mathematical formulation of the attack complexity and statistical evaluation based on simulated PUF data show the strength of this new protocol.