Topics and topic hierarchy in IOT Protocols - Mini Project: Build & Apply

Understanding MQTT Topics and Topic Hierarchy

📖 Scenario: You are working with an MQTT messaging system used in smart home devices. MQTT uses topics to organize messages so devices can subscribe to the right information.Topics are like addresses or folders where messages are sent and received. They have a hierarchy separated by slashes, like home/livingroom/temperature.

🎯 Goal: Learn how to create MQTT topics and understand their hierarchy by building topic strings step-by-step.

📋 What You'll Learn

Create a base topic string for a smart home

Add a room name as a subtopic

Add a sensor type as a subtopic

Print the full topic string

💡 Why This Matters

🌍 Real World

MQTT topics organize messages in IoT systems like smart homes, factories, and vehicles.

💼 Career

Understanding MQTT topics is essential for IoT developers and DevOps engineers managing device communication.

1

Create the base topic

Create a variable called base_topic and set it to the string "home".

IOT Protocols

# Create a variable called base_topic and set it to "home"
# Your code here

Need a hint?

Think of base_topic as the main folder for all smart home messages.

2

Add the room name

Create a variable called room and set it to the string "livingroom". Then create a variable called topic_with_room that joins base_topic and room with a slash / between them.

IOT Protocols

base_topic = "home"
# Create a variable room with value "livingroom"
# Create topic_with_room by joining base_topic and room with '/'
# Your code here

Need a hint?

Use string concatenation with "/" to build the topic hierarchy.

3

Add the sensor type

Create a variable called sensor and set it to the string "temperature". Then create a variable called full_topic that joins topic_with_room and sensor with a slash / between them.

IOT Protocols

base_topic = "home"
room = "livingroom"
topic_with_room = base_topic + "/" + room
# Create a variable sensor with value "temperature"
# Create full_topic by joining topic_with_room and sensor with '/'
# Your code here

Need a hint?

Keep adding levels to the topic by joining strings with slashes.

4

Print the full topic

Write a print statement to display the value of full_topic.

IOT Protocols

base_topic = "home"
room = "livingroom"
topic_with_room = base_topic + "/" + room
sensor = "temperature"
full_topic = topic_with_room + "/" + sensor
# Print the full_topic variable
# Your code here

Need a hint?

Use print(full_topic) to show the complete topic string.