AIS Data Analysis: Reality in the Sea of Echos

The global trend of progressive digitalisation of the world is affecting many industries, including the maritime transport sector. Electronic navigation equipment used on board modern ships has undoubtedly decreased naval accidents over the years, but these devices may suffer from cyber security vulnerabilities. The Automatic Identification System (AIS) is a well-studied navigational system with considerable weaknesses. Many publications discuss different methods for detecting anomalies in AIS. Still, validation is often missing or based on synthetic data because of the lack of publicly available AIS datasets, collected from real environments. To satisfy the need for such a dataset, we collected AIS data for six months with a receiver installed near the shore. This paper presents both the dataset and the analysis of the collected data from different perspectives; highlighting the differences between the expected and realistic features of AIS data. In our research we identified several anomalies regarding the AIS transmission propagation and periodicity, and the ship’s positional data. We believe that our realistic dataset, with its labelled anomalies, will serve as an ideal testbed for developing AIS-related anomaly-detection systems.