AIS broadcasts information in three broad categories: static, dynamic and voyage-related. Shipborne AIS uses static data, dynamic data that is automatically updated by sensors apart from manually entered navigational status, and voyage-related data that is maintained manually. The three categories do not share one method of entry or updating.
AIS is a cooperative VHF data system through which equipped ships and shore facilities automatically exchange identity, position, course, speed, navigational status and other safety-related information.
The built-in integrity test can report equipment malfunction, but it does not validate the accuracy of connected sensor data. Routine checks and corroboration remain necessary.
