EGC is a message broadcast service within the Inmarsat-C communication system.
It allows terrestrial information providers to pass messages or data to JUE-85 Inmarsat-C MES.
EGC messages are sent to Land Earth Station by shore based Information Providers using
terrestrial facilities such as Telex, and are processed at the LES, and forwarded to an NCS then are
broadcasted to the INMARSA-C MES via NCS common channel transmitted by NCS.
There are three basic services offered by EGC; the Safety NET service, the Fleet NET service and
System service. Safety NET is a service provided primarily for the dissemination of maritime safety
information, such as shore to ship distress alerts, weather forecasts and coastal navigational warning.
The JUE-85 has following two kinds of receive mode;
“Inmarsat-C” mode :EGC message can be received when Inmarsat-C mode is not communicated.
(Vessel usaually set up this mode except in special case)
“EGC receive only” mode: EGC message can be received continuously and Inmarsat-C mode may
be ignored.
Fleet NETTM is a commercial communication service allowing terrestrial information providers to send messages to pre-defined groups of subscribers. System service is a service provided for operational information.
Both the Safety NET and Fleet NET services make use of flexible addressing techniques to allow
the reception of messages from a variety of service providers depending on the particular requirements of
the user. The Safety NET service utilizes a geographic area addressing technique to direct messages
to ships within defined boundary. The Fleet NET service employs closed user group and unique
receiver addressing to provide secure transmission of messages from the terrestrial information provider
to the desired service recipients(s).
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