Symbiotic Federated Learning for Giant AI Threat Detection in 6G-IoT Infrastructures

The increasing demand for intelligent, privacy-aware, and scalable solutions at the edge of the network is accelerating the convergence of Giant AI models and Internet of Things (IoT) infrastructures in 6G environments. In this article, we propose a symbiotic threat detection framework that unifies federated learning (FL), graph neural networks (GNNs), and HE to enable decentralized anomaly detection across distributed 6G-enabled IoT ecosystems. Our approach addresses key challenges in current cloud-centric architectures, including data privacy, communication efficiency, and lack of interpretability in AI-driven threat detection. The proposed framework, SymFL-GNN, supports collaborative learning among IoT devices while retaining data locally, leveraging the PHC to ensure gradient-level encryption. To enhance interpretability, a dynamic sensor graph is constructed using self-learned embeddings and attention mechanisms, allowing the model to pinpoint anomalous behaviors and their sources. We evaluate our framework on two real-world industrial datasets (SWaT and WADI) representing cyber-physical water systems, achieving 96.3% and 96.0% accuracy, respectively, with significant improvements over existing baselines in both precision and F1 score. Our results show that SymFL-GNN effectively balances local autonomy with global intelligence, supporting the vision of symbiotic AI at the edge. The framework demonstrates how 6G-enabled IoT networks can jointly contribute to and benefit from Giant AI models, laying the foundation for secure, intelligent, and privacy-preserving distributed systems in critical infrastructure and consumer environments.