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MQTT set up Flask

 MQTT

Introduction:

It is message broker which holds the data when ever a consumer will connected to the topic then he will receive the data . mqtt is a machine to machine message broker, mainly used in IOT application, the default port is 1883


 

Installation:

sudo apt-get update
sudo apt-get install mosquitto

Command line execution:

Producer

mosquitto_pub -h 127.0.0.1 -t 'topic_name' -m '{'name':'Sony'}'

Subscriber

mosquitto_sub -h 127.0.0.1 -t 'topic_name'


-h : it is the host address

-t : topic name

-m : message payload

QOS in MQTT:

QOS(quality of services) there are mainly 3 services are available in mqtt 

  1. qos=0
  2. qos=1
  3. qos=2

QOS (0,0):

At most once service, publisher will send a message to broker at most once, the broker passes a message to subscriber one time 
 

 

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