OSI Model

Open System Interconnection model is no longer for network team. In today’s world ,it become essential knowledge for everyone in tech industry.

The OSI model is a framework for understanding how computers communicate with each other.

In OSI model we have seven steps or layers that information takes from one computer to another.

Every layer has specific job and these job need to done in a certain order ,like when you send a letter through a post office.

To remember this layers we have shortcut like “Please Do Not Take Silly People’s Advice”.

1. Physical Layer(Layer 1): Like a mail truck ,this layer is responsible for the actual delivering of the data. It establishes ,maintains and deactivates the physical connection. In a computer ,it’s the physical parts like the cables and wires that carry the data from one computer to another.
2. Data Link Layer(Layer 2):This layer is like the sorting process at the post office, it prepares the data for transport on the physical layer by packing it up and adding a delivery address.
3. Network Layer(Layer 3): This is like the postman finds the best route to delivery the letter. This layer finds the best path for data to get its destination in a shortcut way and calculating the cost and all.
4. Transport Layer(Layer 4):We can say this layer as a security check. It ensures the data arrives safely without errors. Like making sure that our letter isn’t damaged when it arrives.
5. Session Layer(Layer 5):This layer is like making sure the mail is delivered to the correct mailbox, it establishes, maintains and ends communication with the receiving device.
6. PresentationLayer(Layer6):After passing all the layer finally the letter reached to the respective person, the person who opens the letter and translate it into the language we understand it. It changes the data into the format that the receiving computer can understand.
7. Application Layer(Layer7):This is like the contents of letter. This is the data that the user interacts with like web browser.