Robust Distributed Anomaly Detection Using Optimal Weighted One-Class Random Forests

Wireless sensor networks (WSNs) have been widely deployed in various applications, e.g., agricultural monitoring and industrial monitoring, for their ease-of-deployment. The low-cost nature makes WSNs particularly vulnerable to changes of extrinsic factors, i.e., the environment, or changes of intrinsic factors, i.e., hardware or software failures. The problem can, often times, be uncovered via detecting unexpected behaviors (anomalies) of devices. However, anomaly detection in WSNs is subject to the following challenges: (1) the limited computation and connectivity, (2) the dynamicity of the environment and network topology, and (3) the need of taking real-time actions in response to anomalies. In this paper, we propose a novel framework using optimal weighted one-class random forests for unsupervised anomaly detection to address the aforementioned challenges in WSNs. The ample experiments showed that our framework not only is feasible but also outperforms the state-of-the-art unsupervised methods in terms of both detection accuracy and resource utilization.