Here I am briefly describing OSI Model and its a layer

1. OSI(ISO)
OSI model full form is Open System Interconnection Model. It created in 1976.It was the first standard
model for network communication, accepted in 1980. It was created by International Organization for
Standardization.
It is a conceptual framework used to describe the functions of a networking system.
It has 7 layers:
1.Physical,
2.Data Link,
3.Network,
4.Transport,
5.Session,
6.Presentation,
7.Application
Here, physical – application works when data is received. And application – physical works when data is
send.
 Application – session  user support layer
 Transport  heart of OSI
 Network – Physical  network support layer
Technique  Aj pher Se Test nahi dena paraga
Here, I described this 7 layers of OSI model:
1. Application :
The application layer interact directly with the software application. This layer produce the data,
which is transfer by network.
Like: Messenger, Email.

2. 2. Presentation:
This layer also called translation layer. Here, data change or we can say modified here like
Encryption/ Decryption.
3. Session:
This layer is responsible for establishment of connection between two devices like sender,
receiver. It called end-end process.
4. Transport:
This is heart of OSI model. This layer accepts the data from the session layer and it breaks into
smaller unit. So, Transport layer also called segment layer.
5. Network:
This layer transfer one host to another host using IP address.
6. Data Link:
Here data change to bits and responsible for the host to host delivery of the data. The main
function of this layer is to make sure data transfer is error-free from one host to another, over the
physical layer. Using MAC address.
7. Physical:
It transfer data from host to host.
And cycle carry on.