A Trust-Centric Blockchain-Enabled Fair Cooperative Spectrum Sensing System for IoT Networks

By integrating cognitive radio (CR) functionality into the Internet of Things (IoT), the CR-based IoT network offers a promising solution to the spectrum scarcity problem faced by traditional IoT systems. However, accurate and fair cooperative spectrum sensing (CSS) faces many challenges, such as malicious nodes’ presence, sensor behavior reliability, and IoT devices’ limited energy. In this article, we propose a lightweight blockchain-enabled CSS system that enhances transparency and reliability in sensing report exchange and fusion. Specifically, we introduce a comprehensive trust evaluation algorithm and a fair sensor selection method to assess the reliability of sensors and fairly assign spectrum sensing tasks. To ensure the decentralization and security of IoT networks, we propose a lightweight consensus mechanism which utilizes trust value and deposits to determine voting weights during producer elections while removing malicious nodes by blocklist mechanism. A smart contract is also designed to automate the entire CSS process, including spectrum sensing, deposit management, and trust management. Finally, security analysis and numerical simulations are conducted to demonstrate the effectiveness and robustness of the proposed blockchain-enabled CSS system.