OSI Model

The OSI Reference Model provides the following advantages:
1. it promotes interoperability
2. defines how to connect adjacent layers
3. compartmentalizes components
4. allows a modular design
5. serves as a teaching tool
6. simplifies troubleshooting.
OSI Model
(Layer 7)The application Layer provides the user interface.
(Layer 6) The presentation Layer defines how information is presented to the user.
(Layer 5)The session Layer determines whether a network connection is needed and initiates the setup and teardown of connections.
(Layer 4)The transport Layer handles the mechanics of reliable or unreliable services.
(Layer 3)The network Layer creates a logical topology with logical addresses. Routers function at this layer.
(Layer 2)The data link Layer assigns physical (MAC) addresses and defines how devices on a specific media type communicate with each other. Bridges, switches, and NICs operate at this layer.
(Layer 1)The physical Layer handles all physical properties for a connection. Hubs and repeaters function here.