MQTT

MQTT (Message Queuing Telemetry Transport) is a messaging protocol designed for IoT devices. It is lightweight and efficient, making it ideal for use in situations where network bandwidth is limited or the devices have limited processing power.

MQTT uses a publish/subscribe model, where messages are published by devices to a broker, which then sends the messages to subscribers. The broker acts as a mediator between the devices and subscribers, ensuring that messages are delivered efficiently.

MQTT messages are made up of three parts: a topic, a message, and a quality of service (QoS) level. The topic is a string that identifies the message, while the message contains the actual data being sent. The QoS level determines the reliability of the message delivery - there are three levels: QoS 0 (at most once), QoS 1 (at least once), and QoS 2 (exactly once).

In the context of an IIoT platform, MQTT is often used as the protocol for devices to send data to the platform. Devices like Raspberry Pi and ESP32 can be configured to publish data to the MQTT broker, and the IIoT platform can subscribe to these topics to receive the data.

Overall, MQTT is a reliable and efficient messaging protocol for IoT devices, and it plays a key role in the communication between devices and IIoT platforms like the one you mentioned.