Facts and notes on the OSI reference model

1. The OSI reference model has seven layers and is divided into two groups.
2. The top three layers define how the applications within the end stations will communicate with each other and with users.
3. The bottom four layers define how data is transmitted end to end.

The upper layers of the OSI reference model include

1. Application layer
2. Presentation layer
3. Session layer

*Note: Users interfaces with computer at the application layer.

*Note: The upper layers are responsible for applications communications between hosts.

Diagram