LWE‐IoT: Evaluating Lightweight Encryption Schemes in MQTT and CoAP IoT Protocols

ABSTRACT There are currently 18.8 billion Internet of Things (IoT) devices online worldwide. The number is expected to rise to 41 billion in 2030 due to technological advances such as 5G. IoT devices are typically cheap, with constrained resources and very limited computing capabilities. This work provides an LWE‐IoT framework to evaluate the performance of lightweight encryption (LWE) schemes in two widely used IoT communication protocols, MQTT and CoAP. For this purpose, a secure IoT network is established based on MQTT and CoAP protocols. Subsequently, it is used to evaluate five LWE schemes: ASCON, PRESENT, SIMON, SPECK, and ChaCha20. The evaluation is conducted by exchanging various payload sizes across the network, both for the MQTT and CoAP protocols. The edge nodes are implemented using an ESP32 microcontroller, while the MQTT broker is implemented on a desktop running Windows 10 operating system. The payload size ranges from 32 to 256 bytes and is divided into small, medium, and large payload categories. Moreover, a comprehensive benchmark is established to evaluate the quantitative analysis based on useful evaluation metrics such as flash storage, encryption/decryption time, latency, and RAM usage. The implementation results reveal up to improvement in encryption and decryption times for ASCON, whereas RAM usage in the case of ChaCha20 and SIMON is reduced by over . Our implementation and associated libraries are open source for reproduction and further improvement.