AIS standards stemmed from the need to make busy waterways safer. The International Maritime Organisation (IMO) recognised this, and created carriage requirements for AIS, these stipulate vessels of a certain size and type have to carry AIS devices. 

Once the carriage requirements had been agreed, the International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA) and the International Telecommunications Union (ITU) create the standards that all AIS devices are measured against. Drawing on many years experience of the marine and communications sectors, this is where it is decided how AIS will work.

Once those standards have been decided, the International Electrotechnical Commission (IEC) create test standards which the devices are measured against. These standards are regulated by the individual countries, members of the IMO, who create their own approval awards. For more information on the approval awards, visit the Approvals and certification page.

Only AIS devices that are used on SOLAS vessels - Class A transceivers and SARTs - are regulated by the IMO. All other AIS devices are regulated on a nation by nation basis. For more information, visit the national approval authorities page.

For more information on the AIS standards and testing and certification procedure, visit the Standards section.

AIS is a relatively simple concept as it uses VHF and GPS to transmit data to other ships increasing the safety, and fun aspect of sailing.

Read more: AIS basics


AIS  Automatic Identification System
AIS approvals  Nationally set minimum requirements for relevant AIS products
AIS base station  An onshore AIS unit that monitors traffic in the waterways
AIS command centre  An AIS system that monitors AIS base stations along a coastline
AIS messages  AIS data is sent in messages to other devices via the AIS slot map
AIS Slot Map  Time slots of 26.6 milliseconds that AIS devices transmit data into
Antenna Splitter  A unit that manages how the VHF antenna is used by the radio and AIS device
AtoN  Aid to Navigation, AIS on a buoy out to sea
CCNR (Central Commission for Navigation of the Rhine) Organisation that regulates AIS devices on inland waterways in Europe
CE (Conformité Européenne, European Conformity)  Organisation that regulates all non SOLAS vessel AIS products in Europe
Class A  A transceiver unit designed for SOLAS vessels that fall under the IMO mandate
Class B  A transceiver unit that offers AIS functionality to all non SOLAS vessels
Carrier Sense Time-Division Multiple-Access (CSTDMA)  A system used by Class B based units to transmit data
Fixed Access Time-Division Multiple-Access (FATDMA)  A system used by AtoNs to transmit data
FCC (Federal Communications Commission)  Organisation that regulates radio devices in America
Glonass  A Russian based positioning system that AIS uses to calculate where the vessel is
GPS  Positioning system that AIS uses to calculate where the vessel is
Incremental Time-Division Multiple-Access (ITDMA) A system used by AIS devices to transmit data
IC (Industry Canada)  Organisation that regulates radio devices in Canada
IEC (International Electrotechnical Commission)  Organisation that sets the AIS test standards for the IMO
IMO  the International Maritime Organisation, the governing body of international maritime transportation
Man overboard  A small device that monitors crew who are working on a vessel
Mandate  A law that specifies AIS for certain vessels. Both national and international laws are referred to as mandates
Pre-Announced Time-Division Multiple-Access (PATDMA)  A system used by SARTs to transmit data
Random Access Time-Division Multiple-Access (RATDMA)  A system used by AtoNs to transmit data
Receive  Receive data from other AIS devices via the AIS slot map
Receiver  A unit that only receives data
SART  Search and Rescue Transponder, alerts ships in range that there is a lifeboat needing assistance
SOLAS  Safety of Life at Sea regulations created by the IMO
Self Organised Time-Division Mulitple-Access (SOTDMA)  A system used by Class A units to transmit data
Transport Canada  Organisation that regulates AIS devices in Canada
Transceiver  A unit that both transmits and receives data
Transmit  Sending data to other ships, shore based stations and AtoNs via the AIS slot map
United States Coast Guard  Organisation that regulates AIS devices in America
VDL  The VHF Data Link the technical term for the AIS slot map
VHF radio  The technology that AIS uses to transmit data to the AIS slot map
Wheelmark  Approval award from the European Union for all SOLAS vessel AIS units


AIS is an extremely flexible technology that gives many benefits to mariners. Aside from the safety benefits offered, AIS is fun to use and allows you to track other vessels.

Benefits of AIS include:

Anti Collision

AIS is able to identify potential collisions by plotting the heading and speed of vessels within range.  Using this information, a live map of the area is constructed, identifying potential collisions and warning mariners so they can make course adjustments.


AIS aids national security by identifying threats to a sovereign border before they reach dry land. Working with radar, AIS identifies ships using AIS; whilst radar identifies vessels that don't have the system and may be potential targets.



Monitoring port traffic allows efficient transfer of vessels between harbours and the sea. It also identifies potential accidents within the port and identification of berths for ships entering the port.



AIS enhances the fun aspect of boating. AIS sends vessel identification details as part of the AIS messages, allowing easy identification of friends, spotting what vessels are in your environment and also direct ship to ship communication as the DSC details are transmitted.



Ship to ship communication is improved using AIS technology. A vessel's DSC details are included in AIS transmissions which enable direct communications with another ship. This reduces the need for using VHF and sending a random transmission out to all ships within range. Further communication channels are also incorporated into the AIS system including text facilities.


AIS offers many solutions to information gathering for organisations. Aids to Navigation can include many different inputs to allow sensors to monitor hydrological and metrological factors; base stations can monitor vessels and AtoNs within their range; and AIS receivers offer a low cost vessel monitoring solution for ports.


AIS was initially designed as an anti collision device, by identifying potential collisions before they happen and allowing vessels to make course adjustments to avoid them. However, recently AIS has enhanced rescue of stranded life rafts by transmitting their course and speed, enabling vessels to plot an intercept course.

Compared to other marine navigation technology, AIS is a relatively new innovation. However, in little over ten years, the technology has come a long way including international mandates, technological developments and international standards.

Historically, other forms of marine navigation had been effective in navigating from one place to another; but, with safety in mind, further enhancements were needed. The lack of vessel identification, coupled with time delays and the inability to see headings and speeds led to the development of AIS and the increase in safety especially in busy waterways.

Scroll along the below timeline to view key dates in the development of AIS.