A Performance Study of Crypto-Hardware in the Low-end IoT

Abstract

In this paper, we contribute a comprehensive resource analysis for widely used crypto primitives across different off-the-shelf IoT platforms, and quantify the performance impact of crypto hardware. This work builds on the newly designed crypto subsystem of the IoT operating system RIOT, which provides seamless crypto support across software and hardware components. Our evaluations show that (i) hardware-based crypto outperforms software by considerably over 100 %, which is crucial for nodal lifetime. Despite, the memory consumption typically increases moderately. (ii) Hardware diversity, driver design, and software implementations heavily impact resource efficiency. (iii) External crypto-chips operate slowly on symmetric crypto-operations, but provide secure write-only memory for private credentials, which is unavailable on many platforms.