When ships are at sea, most sailors want to maintain the communication services they are accustomed to e.g. using land - telephony and data/Internet.
This is made possible by satellite communications services - such as Inmarsat's FleetBroadband service or by VSAT-based satellite services.
Inmarsat deliver data services that include voice and data rates of up to 432 kilobits per second. VSAT-based services can deliver higher data speeds. The VSAT equipment is typically larger than Inmarsat's FleetBroadband terminals.
In terms of coverage, the Inmarsat FleetBroadband service is almost providing a global coverage. (70 Degrees North to 70 degrees South).