Automatic Identification Systems is an automated vessel tracking system for seagoing vessels; international voyaging ships above 300 gross tons and all passenger ships are required to be outfitted with AIS. This system communicates vessel location while underway to other vessels and coastal monitoring stations. This helps the with many navigational issues, such as collision avoidance; traffic configuration; maritime security; search and rescue; and accident investigation. Several types of device classes and uses exist for these purposes.
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