Inmarsat-C service activation enables ships and remote users to access satellite communication for messaging, distress alerts, and data transfer. The activation process starts with selecting an authorized service provider. Next, the vessel’s details and terminal specifications are submitted for registration. The provider assigns a unique MES number and configures the system accordingly. A test message is sent to confirm proper functionality. Activation ensures that the terminal can send and receive distress alerts, SafetyNET messages, and commercial data. Proper configuration and periodic testing guarantee uninterrupted service throughout the voyage.