# MQTT

## Introduction

The **MQTT Nodes** provide a means for the user to perform several actions within the *MQTT* messaging protocol. *MQTT*, or *Message Queuing Telemetry Transport*, allows the communication among devices and is commonly used in *IoT* applications. To use the **MQTT Nodes** in **Incari**, the user needs to locate the [**MQTT Attributes**](https://docs.incari.com/incari-studio/v/2021.2/modules/project-settings#mqtt) in **Project Settings** and add a `Connection`.

## Contents

* [**Events**](/incari-studio/2021.2/toolbox/communication/mqtt/events.md)
* [**MQTT Start**](/incari-studio/2021.2/toolbox/communication/mqtt/mqttstart.md)
* [**MQTT Stop**](/incari-studio/2021.2/toolbox/communication/mqtt/mqttstop.md)
* [**MQTT Subscribe**](/incari-studio/2021.2/toolbox/communication/mqtt/mqttsubscribe.md)
* [**MQTT Publish**](/incari-studio/2021.2/toolbox/communication/mqtt/mqttpublish.md)

## External Links

* [*More information on MQTT*](https://en.wikipedia.org/wiki/MQTT) on Wikipedia.
* [*An in-depth explanation and tutorials*](https://mqtt.org/) on MQTT.
* [*An in-depth explanation of Topics*](http://www.steves-internet-guide.com/understanding-mqtt-topics/#:~:text=%20Understanding%20MQTT%20Topics%20%201%20The%20%24SYS,publish%20to%20an%20individual%20topic.%20That...%20More%20)


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