Designing a Secure and Scalable Service Model Using Blockchain and MQTT for IoT Devices

Tse-Chuan Hsu, Han-Sheng Lu; Proceedings of the IEEE/CVF Winter Conference on Applications of Computer Vision (WACV) Workshops, 2024, pp. 645-653

In the realm of Internet of Things (IoT) communication, where many devices operate within resource-constrained environments, the MQTT communication protocol is often employed to establish a swift and efficient network for sharing and exchanging data. However, MQTT poses certain limitations. It primarily supports message broadcasting rather than point-to-point data exchange. Each endpoint can merely broadcast messages to other endpoints subscribed to the same topic. Furthermore, MQTT lacks built-in encryption mechanisms, leaving data transmission vulnerable to potential eavesdropping. In response to these shortcomings, this research leverages blockchain technology and enhances it with features such as public and private key management, broadcasting, and message verification. The objective is to enhance communication quality and ensure the reliability of message encryption. To achieve this, every device within the network is equipped with the public keys of other devices through a broker broadcast. Before encrypting a message using these public keys, a verification step is performed to ensure the consistency of public keys across all devices. This approach facilitates Message on Transmission Protocol (MTP),Subject-Specific Communication Protocol (SSCP) and mitigates the risk of compromised public keys. This research's theoretical underpinnings are substantiated through experimentation. In the experimentation, it is demonstrated that the experimental performance of this architecture, whether with 3 devices, 10 devices, or 100 devices, exhibits a latency almost difference of less than 1 second. Therefore, this validates that our designed architecture not only enhances security but also boasts excellent performance.