Describe the OSI model?

Open System Interconnection, an ISO standard for worldwide communications that defines a networking framework for implementing protocols in seven layers.The seven layers are :

1) Application Layer:

2) Presentation Layer:

3)Session Layer:

4) Transport Layer:

5) Network Layer:

6) Data Link Layer:

7) Physical Layer:

Hi Open System Interconnection, an ISO standard for worldwide communications that defines a networking framework for implementing protocols in seven layers.The seven layers & Functions are: 1)Application Layer: Data in the form of Messages. 2)Presentation Layer: Data in the form of segments. 3)Session Layer : Data in the form of segments. 4)Transport Layer : Date in the form of segments. 5)Network Layer : Data in the form of Packets. 6)Datalink Layer : Data in the form of Frames. 7)Physical Layer : Data in the form of Bits. 1) Application Layer:Interface between user and network.It provide user interface application. 2) Presentation Layer:Negoiate the data exchange format. 3)Session Layer:Allow user to establish connection using easily remember names. 4) Transport Layer:Provides end to end reliable transfer. 5) Network Layer:Routes the data through a large network. 6) Data Link Layer: it determine access to the network media. 7) Physical Layer:it convert frames into bits.

Open system interconnecting its a standerd model by ISO for comminication all over the world .

Its seven layer

1. Application layer:- Example Like TElnet

2. Prestation Layer:- Encoding,decoding data or How to present like jpg many other

3. Session layer: It creat session Between the application

4. Transport Layer: It Transfer the data (UDP and TCP)

5. Network Layer:IT determine the path or packect swiching

6. Data Link Layer: It depend on LLC

7. Phisical Layer: Examle cable or hub

Why do need such type of models, What is its significance?

it provides modularity.
if suppose performance of one layer can be improved we need not throw the whole model but just change that layer.
e.g. if something in a computer goes wrong we can change that part instead of throwing away whole computer

OSI Model Stands for Open System Interconnection
It has 7 layers

Application Layers
Presentation Layers
Session Layers
Transport Layers
Network Layers
Data Link Layers
Physical Layers

OSI Modal is a network standardization modal, which define network standard, any networking device or Protocol will either follow OSI standard or will not follow OSI Model.

OSI design by ISO (International Organisation Of Standardization).

OSI is divided into SEVEN Layer,

Ascend,
Physical,
Datalink,
Network,
Transport,
Session,
Presantation,
Application.

Every Layer has a specific function