iSTELLAR: intermittent Signature aTtenuation Embedded CRYPTO with Low-Level metAl Routing

Abstract

An adversary can exploit side-channel information such as power consumption, electromagnetic (EM) emanations, acoustic vibrations or the timing of encryption operations to derive the secret key from an electronic device. Signature aTtenuation Embedded CRYPTO with Low-Level metAl Routing (STELLAR) is a technique to mitigate power and EM-based attacks, however, it incurs 50% power overhead. This work presents iSTELLAR, which reduces the power overhead by operating STELLAR intermittently utilizing an intelligent scheduling algorithm. The proposed scheduling algorithm for iSTELLAR determines the optimal locations during the crypto operation to turn STELLAR ON, and thereby reduces the power overhead by $> 30\%$ compared to the normal STELLAR operation, while eliminating the information leakage.