Hybrid architectures for efficient and secure face authentication in embedded systems

In this paper, we propose an efficient and secure embedded processing architecture that addresses various challenges involved in using face-based biometrics for authenticating a user to an embedded system. Our paper considers the use of robust face verifiers (PCA-LDA, Bayesian), and analyzes the computational workload involved in running their software implementations on an embedded processor. We then present a suite of hardware and software enhancements to accelerate these algorithms - fixed-point arithmetic, various code optimizations, generic custom instructions and dedicated coprocessors, and exploitation of parallel processing capabilities in multiprocessor systems-on-chip (SoCs). We also identify attacks targeted against the authentication process, and develop security measures to ensure the integrity of biometric code/data. We evaluated the proposed architectures in the context of popular open-source software implementations of face authentication algorithms running on a commercial embedded processor (Xtensa from Tensilica). Our paper shows that fast, in-system verification is possible even in the context of many resource-constrained embedded systems. We also demonstrate that the security of the authentication process for the given attack model can be achieved with minimum hardware overheads.