A new security architecture for smartcards utilizing PUFs

Abstract

Physical Unc10nable Functions (PUFs) are functions embodied in physical structures which are easy to evaluate but hard to predict. Furthermore implementations are practically impossible to duplicate, even if the exact manufacturing process is known and available. As a consequence, security architectures based on PUFs promise inherent unclonability, physical tamper resistance and secure establishment of device-unique cryptographic keys. Well-known bare silicon PUFs aim at the security of the circuit itself but do not grant tamper resistance to the card in which it is embedded. In this paper, we propose a new security architecture for smartcards utilizing material-based PUFs. where the measurement circuitry is integrated into the smartcard controller and the PUF structure is part of the card material surrounding the chip. This PUF system is considered resistant against laser fault injection attacks and micro probing, since any physical change results in different measurement data and therefore in altered PUF responses. The proposed architecture builds upon optical PUFs and includes the generation of complex stimulation signals from an array of LEDs, material surrounding the chip with unique optical responses, techniques for measuring the optical material responses, and means for cryptographic key generation. © Springer Fachmedien Wiesbaden 2012.