Transmission type

The messaging app uses various transmission types for different kinds of messages; these are: secure, non-secure, and safety related.

Messaging app Transmission typeFirst responder Messaging appThe available transmission types are dependent on AIS transceiver mode:

• Restricted — In restricted mode, only secure messages can be sent.

• Normal — In normal mode, the transmission type can be set to secure, non-secure or safety related.

• Receive only — In receive-only mode, messages cannot be sent but can still be received.

The transmission types are explained below:MessagesCharacter limit

• Secure — Secure messages can only be received by vessels that are using the same STEDs passphrase as the sender/broadcaster. Secure broadcast messages are limited to 79 characters in length. Secure direct messages are limited to 57 characters.

• Non-secure — Non-secure messages can be received by any vessel with a STEDs-compliant AIS transceiver, and does not require recipients to have the same STEDs passphrase as the sender/broadcaster. Non-secure broadcasts are limited to 86 characters in length. Non-secure direct messages are limited to 80 characters.

• Safety related — Safety-related messages can be received by any vessel with a STEDs-compliant AIS transceiver. This transmission type does not require recipients to have the same STEDs passphrase as the sender/broadcaster. Safety-related broadcasts are limited to 90 characters in length. Safety-related direct messages are limited to 85 characters.