A LOW AREA OVERHEAD SPA-RESISTANCE EDWARDS25519 ACCELERATOR FOR IOT BIOSENSORS

An area-efficient Edwards25519 accelerator for biosensors is successfully developed and validated by this study. To achieve low area overhead of the ECC implementation on biosensor devices, this paper proposes an Edwards25519 accelerator with a unified point addition formula in projective coordinates. The unified point addition formula has the advantage of not only saving the area of point multiplication module, but also the resistance to simple power analysis (SPA). With our rescheduling on the unified point addition formula, it costs only four modular radix-2 multipliers, one modular adder, and one modular subtractor. A non-adjacent form rearrangement is applied to the secret scalar to save the computation time of double-and-add algorithm and confuse the attempted side-channel analysis (SPA). This proposed Edwards25519 accelerator, implemented on the AMD Xilinx Virtex-7 platform, achieves the lowest area requirement with resistance to SPA compared to the state of the art and the competitive performance on the product of area and computation time, making it the most appropriate Edwards25519 accelerator for low-cost biosensor devices.