Book Image

MQTT Essentials - A Lightweight IoT Protocol

5 (1)
Book Image

MQTT Essentials - A Lightweight IoT Protocol

5 (1)

Overview of this book

This step-by-step guide will help you gain a deep understanding of the lightweight MQTT protocol. We’ll begin with the specific vocabulary of MQTT and its working modes, followed by installing a Mosquitto MQTT broker. Then, you will use best practices to secure the MQTT Mosquitto broker to ensure that only authorized clients are able to publish and receive messages. Once you have secured the broker with the appropriate configuration, you will develop a solution that controls a drone with Python. Further on, you will use Python on a Raspberry Pi 3 board to process commands and Python on Intel Boards (Joule, Edison and Galileo). You will then connect to the MQTT broker, subscribe to topics, send messages, and receive messages in Python. You will also develop a solution that interacts with sensors in Java by working with MQTT messages. Moving forward, you will work with an asynchronous API with callbacks to make the sensors interact with MQTT messages. Following the same process, you will develop an iOS app with Swift 3, build a website that uses WebSockets to connect to the MQTT broker, and control home automation devices with HTML5, JavaScript code, Node.js and MQTT messages
Table of Contents (16 chapters)
MQTT Essentials - A Lightweight IoT Protocol
About the Author
About the Reviewer
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Understanding the requirements

In the previous chapters, we learned how MQTT works in detail. We understood how to establish a connection between an MQTT client and an MQTT server. We learned what happened when we subscribed to topic filters and when a publisher sent messages to specific topics. We installed and secured a Mosquitto server. Then, we controlled a drone with Python.

Now, we will use Java as our main programming language to generate MQTT clients that will act as publishers and subscribers. We will connect a Java MQTT client to the MQTT server and we will process simple commands to control sensors with MQTT messages.We will use TLS encryption and TLS authentication because we don't want any MQTT client to be able to send commands to sensors wired to IoT boards. We want our Java code to run on many platforms because we will use the same code base to control sensors that use the following IoT boards:

  • Raspberry Pi 3

  • Raspberry Pi 2 Model B

  • Intel Edison

  • Intel Galileo Gen 2

  • Intel Joule 570x...