Describe the encapsulation process in the OSI reference model?

Describe the encapsulation process in the OSI reference model?

In data encapsulation process, OSI model is a guideline. It tells the computer what it's supposed to do when data needs to be sent or when data is received.

OSI Model consists of 7 layers which play different roles during data encapsulation process. In other words, Data encapsulation process is divided into different parts or processes completed by 7 layers of OSI model.

For example, If a computer in a network needs to send data to another computer, The Application layer provides graphical user interface, here the user interacts with the application he is using,

After that this data is passed to the Presentation layer and then to the Session layer. These layers add some extra information to the original data that came from the user (for example, Session layer creates virtual sessions) and then passes it to the Transport layer. Here the data is broken into smaller pieces and TCP (transmission control protocol) header is added.

Each segment of the data is then handed over to the Network layer for logical addressing and routing through the internet network.

The Network layer add its IP header and then sends it off to the Datalink layer. Datalink layer converts the data into frame. The Datalink layer is responsible for taking packets from the Network layer and placing them on the network medium (cable). The Datalink layer encapsulates each packet in a frame which contains the hardware address (MAC) of the source and destination computer (host) and the LLC information which identifies to which protocol in the previous layer (Network layer) the packet should be passed when it arrives to its destination.

If the destination computer is on a remote network, then the frame is sent to the router or gateway to be routed to the destination. To put this frame on the network, it must be put into a digital signal. Since a frame is really a logical group of 1's and 0's, the Physical layer is responsible for encapsulating these digits into a digital signal which is read by devices on the same local network.