MQTT is a messaging protocol that allows devices to publish and subscribe to messages or "topics" through a broker. Publishers connect to the broker to publish content to topics, subscribers connect to the same broker to subscribe to topics they are interested in. The broker ensures published content is distributed to subscribers. Topics use a tree structure separated by forward slashes, and wildcards like # can subscribe to entire branches. An example shows sensors publishing temperature data to topics and a subscriber using wildcards to subscribe to multiple sensor topics.

1. MQTT protocol in IoT
Pravesh Kumar
pkverma462@gmail.com

2.  Introduction of MQTT
 MQTT terms
 Working of MQTT
 MQTT architecture

3. introduction
 Message Queue Telemetry Transport (MQTT) protocol

Publisher 1
Subscriber
n
Subscriber
1
publisher
Broker

4. MQTT terms
 Publisher:- It connect to server and publish the content
 Subscriber:- It connect to same message broker and subscribe to content
that they are interested in
 Message Broker:- It assured that the published content to its subscriber
 Topic:- Content is identify by topic

5. Topic in mqtt
 Topics are ordered into a tree structure
 The forward slash ( / )is describe as topic path
 Hash wildcard(#) is used to subscribe entire branch
 example
 The publisher send the measured data to “Pravesh/firstIoT/sensors/temperature” topic
 Subscribing to Pravesh/+/sensors/# will subscribe to all subbranches of the sensors class

6. Architecture of MQTT
Local Area Network
Internet Protocol
TCP
MQTT over SSL/TLS
TCP
MQTT
Physica
l

7. Example
ROOM 1
ROOM 2
ROOM 3
HOUSE
TOPIC
HOUSE/ROOM1/temp1
HOUSE/ROOM2/temp2
HOUSE/ROOM3/temp3
HOUSE/+/#

8. Thank you