Federated Learning-Enhanced Blockchain Framework for Privacy-Preserving Intrusion Detection in Industrial IoT

Industrial Internet of Things (IIoT) systems have become integral to smart manufacturing, yet their growing connectivity has also exposed them to significant cybersecurity threats. Traditional intrusion detection systems (IDS) often rely on centralized architectures that raise concerns over data privacy, latency, and single points of failure. In this work, we propose a novel Federated Learning-Enhanced Blockchain Framework (FL-BCID) for privacy-preserving intrusion detection tailored for IIoT environments. Our architecture combines federated learning (FL) to ensure decentralized model training with blockchain technology to guarantee data integrity, trust, and tamper resistance across IIoT nodes. We design a lightweight intrusion detection model collaboratively trained using FL across edge devices without exposing sensitive data. A smart contract-enabled blockchain system records model updates and anomaly scores to establish accountability. Experimental evaluations using the ToN-IoT and N-BaIoT datasets demonstrate the superior performance of our framework, achieving 97.3% accuracy while reducing communication overhead by 41% compared to baseline centralized methods. Our approach ensures privacy, scalability, and robustness-critical for secure industrial operations. The proposed FL-BCID system provides a promising solution for enhancing trust and privacy in modern IIoT security architectures.