An Authentication Scheme for IoT-Based Mechanical Relay Utilizing QR-Code and MQTT

When the Internet of Things (IoT) becomes a new trend and platform of automation and control systems, security in IoT emerges as one of the critical factors for realizing reliable and safe systems for human beings and environments. Due to the low computational resources of IoT devices, common security measures in computer systems can potentially degrade the performance of IoT devices. This research aims to provide a QR-code and MQTT-based authentication scheme for connecting users with intended IoT-based mechanical relay devices. In this scheme, IoT-based mechanical relay devices are by default connected with the IoT systems by using MQTT communication protocol with certain topics. Then, users have to be authenticated by the MQTT broker to connect with the IoT devices. The authentication process uses QR codes to transfer credentials from the IoT devices to the users' mobile applications. After entering the correct username and password combined with the credentials generated from the QR codes, users eventually can access IoT-based mechanical relay devices. The QR code implementation successfully simplifies IoT device onboarding, while the use of AES 256 encryption strengthens security. The performance measurements on Android devices indicate high efficiency, and QR code testing demonstrates success in various conditions. These findings have the potential to improve the security and efficiency of IoT device usage in diverse contexts. Eventually, this research can deliver one alternative security solution for securing IoT device integration and safeguarding critical operations and data.

I. Introduction

In today's rapidly evolving interconnected world, the pro-liferation of the Internet of Things (IoT) has fundamentally transformed how devices and systems communicate and inter-act [1]. However, with the exponential growth in the number of connected devices, the overarching concern of ensuring secure and reliable authentication has become more critical than ever before [2]. Within the vast IoT ecosystem, mechanical relays play a pivotal role as they serve as a bridge between the physical and digital realms, enabling the remote control and management of a wide range of equipment and processes. These mechanical relays, historically used in various critical applications, have now become integral components of IoT networks. Their integration into these networks has introduced new challenges, particularly concerning the security and au-thentication of these devices.