🤖 AI Summary
To address the insufficient adaptability of intrusion detection systems (IDS) in Internet-of-Things (IoT) environments under dynamic threats, this paper presents a systematic review of deep reinforcement learning (DRL) for IoT intrusion detection. It introduces, for the first time, a taxonomy of DRL-based IDS methods specifically tailored to IoT scenarios, uncovering critical research gaps—particularly concerning state representation sparsity and real-time constraints. Empirical evaluations are conducted across heterogeneous datasets (NSL-KDD, CIC-IDS2017, and IoT-specific benchmarks) using representative DRL algorithms including DQN, PPO, and A3C, yielding performance boundaries for 12 canonical method categories. Furthermore, we propose a three-dimensional evaluation framework—encompassing deployability, generalizability, and communication overhead—to rigorously assess practical viability. This work provides both theoretical foundations and actionable guidelines for developing lightweight, adaptive IDS solutions for resource-constrained IoT deployments.