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MQTT

A small publish/subscribe messaging protocol built for devices on unreliable networks.

MQTT is a publish/subscribe protocol over TCP (standardized by OASIS, versions 3.1.1 and 5) with tiny headers, three quality-of-service levels, retained messages and last wills.

Examples

  • MQTT was designed in 1999 to monitor oil pipelines over satellite links; this course teaches version 3.1.1.

  • The greenhouse sensor sends its temperature to an MQTT broker, and any program subscribed to gh/bench1/temp receives it.

See also

publish/subscribe client broker Mosquitto
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