Today we are learning about the communications Model.

  • How will the communication Model happen?
  • How does it follow the different standards to communicate two or more devices for communication?

Today we discuss the communication Model which is used in IoT or IIOT. Before we discuss the communication model, we have to find

Why IoT communication Model is required? 

To understand this let us suppose, How the data establish btw the source or destination?

  1. Whenever two or more devices want to transfer data with security, so we need to follow this Communication Model.
  2. We also need this because whenever we transfer or receive the data which is in the form of packets and they have to be successfully delivered.
  3. We also want this model because in IoT or IIoT the different machines work on operating frequency (diff. speed). Because we didnt want to lose the data, thats why we have to try they will synchronize it, So we need Communication Model.
  4. Different devices are works on different protocols. For example, some devices have HTTP and some are having HTTPS support, So when the machine works on different protocols to interface communication (data combination), So we need this communication Model.

Now we understand which type of different Models we have to learn.

Request Response

In this, we clearly can see understood one device will send the request and another will take send the response. Generally, we used this protocol in a web browser. In this we open our browser and wherever domain will we search on that what will you doYou request the domain to get the information about the search.

How Request will be sent? 

Firstly we search for something on the browser and domain request to the internet and transfer it to servers where all the data was stored. Then will respond or send the information through the internet and display the result to be used by the device ( pc, mobile). And we know this happened in just a second. But this model is based on Request or response. Here we follow the HTTP and HTTPS. It means one device is requested and another gives it a response. so thats the type of working of this model.

Publisher subscriber

Here by the name we see that there is one device will a publisher and another one is a subscriber. Publishers - who send the data are known as publishers. In IoT, all the sensors are our publishers and these sensors send the diff-diff values to brokers and Subscribers - who are interested in that data are known as subscribers. Broker - divide it into topic vice and the subscriber who subscribed the topic data was delivered to it. It is the same as a youtube channel if someone subscribes to the channel then they will get notified of that channels data.


In the same way, you can see one device push the data and another device will pull it as per its name. we can understand it also like, I have a publisher who sends the message to the queue. Because the speed of transmission of data between the transmitter and receiver is different as per based on diff-diff devices. so here publisher works on spending the data one by one and consumers will acquire the information step by step, Here in this model publisher send the data first to the yellow then blue, green, and red then the consumer will acquire it. The consumer will send the data firstly to red then green, blue, and yellow. like first in first out.

Exclusive Pair

Exclusive Pair - we use it in dedicated lease lines. whenever we want to data communicate btw clients or servers to others we use this model.


  1. The client generates the request to start a connection.
  2. When its request will accept then the server sends a request accepting the request.
  3. The data transfer will start btw the client or server.
  4. Once the data transfer was completed the server send a request for data transmission.
  5. When the data transmission is done the client sends a request to the server for connection closed transmission.
  6. The server sends a request to the client for the close connection request.

Because data transmission btw the client or server is in the Full Duplex communication Model. It means Bidirectional communication so we can also be called it the Bidirectional Model.

So all of this discussion in this video is given below.