MQTT is a standards-based messaging protocol which can be used with different message bus implementations. It is considered simple and efficient (it was designed for use on monitoring oil rigs remotely originlly by IBM) so is in wide use for Internet of Things (IoT) devices which operate on battery.
Main benefits:
- Lightweight and efficient: Can be used on embedded devices, network constrained or low power
- Scalable: can support millions of devices
- Secure: can be encrypted and use authentication
- Well-supported: Many bindings in different programming languages
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