What is it?
The Automatic Identification System (AIS) was primarily developed as a collision avoidance tool in the 1990’s. In this capacity, vessel parameters and navigation information are encoded and transmitted by radio in real time. The primary parameters exchanged include location, speed, heading, vessel type and size, and voyage information. Today, AIS data is used in many additional applications, such as traffic analyses and vessel operation characteristics.
How to obtain?
There are some open source options available for terrestrial (coastal) datasets accessible via governments and IGOs. Whereas anyone in a coastal area can record AIS transmissions within their range, signals from vessels offshore can only be registered by satellite. In applications where satellite data from ocean transits is desired, users will likely have to make use of a subscription or credit based service to obtain it.
General Categorization of AIS Data Sources
The sources listed in the AIS Data Sources page will fall into one of these categories.
|Type of Data||Source||How to Obtain?|
|Historical Coastal||Commercial Provider||Buy credits or request quote|
|Government/IGO||Request with justification|
|Live Coastal||Crowdsourced||Free - Manually or API from AISHub|
|Ocean (Satellite), Historical and Live||Commercial Provider||Buy subscription for live feed or request quote for historical data|
Since there are a limited number of land station receivers and satellites, you may find that the datasets from different providers actually originate from the same source. Therefore, it may be worthwhile to shop around with different providers to find the best price.
What vessels use AIS?
The transmission of AIS data is mandated by the IMO for all vessels > 300 GT engaged in international voyages, for all cargo ships > 500 GT not engaged in international voyages, and for all passenger ships regardless of size.