OSI reference model serves as a guide for information exchange. This model divides communication task into seven sub tasks. A different layer handles each task. Layer is an abstraction for the services and protocols at some specific level. Layers are organized in a hierarchical fashion in such a way that a layer produces data and hands it over to the next layer that adds some data (header) or does some processing and transfers the data to the lower layer and in this way data travels through six different layers of OSI model and reaches the physical layer that transmits data in the form of signals and these signals are received by the physical layer at the destination computer. This data then moves up six layers and reaches the application layer in the format it was produced by the application layer in the source device. Following are the seven layers of OSI model:
1. Physical Layer
2. Data Link Layer
3. Network Layer
4. Transport Layer
5. Session Layer
6. Presentation Layer
7. Application Layer
These layers are arranged in the form of stack that means the layer in the source and destination computer work in the reverse order. The Layer that produces the data first in the source computer is the last one to receive that data on the destination device.
1. Physical Layer
2. Data Link Layer
3. Network Layer
4. Transport Layer
5. Session Layer
6. Presentation Layer
7. Application Layer
These layers are arranged in the form of stack that means the layer in the source and destination computer work in the reverse order. The Layer that produces the data first in the source computer is the last one to receive that data on the destination device.