Hands-on evaluation of the cryptographic overhead on wireless sensor networks

Abstract

The Internet of Things (IoT) is a growing research field and one of today’s prime examples of Wireless Sensor Networks (WSN) applicability and possible impact on general society. IoT scenarios use a great diversity of sensors, protocols, and mechanisms widely researched from a system perspective. Unfortunately, the security within the small sensing devices and the impact on those small sensors of choosing one cryptographic solution over the other is still lacking further research. In this paper, we tested different security configurations using the two most used transport protocols (HTTP and MQTT). We measured their effects on five commonly used embedded devices in IoT WSNs: ESP8622, ESP32, RPil, RPi2, and RPi3. We considered three different metrics for evaluating each configuration: Power consumption, message delay, and additional message length (bytes). The experimental results from long runs (60 hours) reveal the cryptographic solution choice is significant for the message delay and additional message length. © 2021 IEEE.