| Primary Use |
Helping ships avoid collisions and assisting port authorities in better monitoring maritime traffic |
Monitoring specifically for commercial fishing vessels that is designed for regulatory bodies to track and manage fishing activities |
Autonomous tracking of vessels of any size, including those not large enough to be well-suited for AIS or VMS systems |
| Vessel Size Class |
International voyaging ships with gross tonnage (GT) of 300 or more, any passenger ship regardless of size, and US fishing vessels |
Varies by location (e.g., USA requires it on any commercial fishing vessel; the EU requires it on any fishing vessel larger than 12m (40ft)) |
Appropriate for vessels of any size, including those without a power source |
| Tracking Interval |
Broadcasts position in real-time (typically every few seconds) to avoid collisions |
Typically sends a position reading once per hour |
Records positions every few seconds, it can also store years' worth of data directly onboard |
| Power Requirements |
Requires power supply |
Requires power supply, or batteries to be recharged regularly |
Completely power-independent using a solar energy |
| Data Communication Method |
Primarily VHF radio but can be supplemented by satellite communication methods |
Satellite based communications |
Cellular Data Network |
| Cost |
$$$ |
$$$$$ |
$ |