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protocol

The agreed rules for an exchange between two parties: what to send, in what order, and what each message means.

A protocol defines the messages two parties exchange, their formats and order, and how each side must respond, including to errors and silence.

Examples

  • The MQTT standard defines the MQTT protocol: which messages a client and broker exchange, in what order, and what to do on a timeout.

  • The Bluetooth Core Specification is one standard that defines several protocols, such as advertising and GATT.

See also

standard broker command
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