What it is
Marine cellular uses standard mobile networks reached through high-gain antennas and routers on board, working whenever the ship is within range of coastal coverage.
How it fits
It is ideal for offloading large data such as logs, backups and media cheaply when near port, acting as an extra low-cost tier in the hybrid stack.
Limits
Range is confined to coastal zones; once offshore, the vessel falls back to satellite. Roaming agreements affect cost and availability across regions.