osi model

Open Systems Interconnection (OSI) Model

A conceptual framework used to understand how network communication functions, published by ISO in 1984.

What are the seven layers of the OSI model?

Physical, Data Link, Network, Transport, Session, Presentation, Application.

What does the physical layer handle?

The physical layer deals with the physical transmission of data over the network medium.

What is encapsulation in the OSI model?

Encapsulation is the process of wrapping data with the necessary protocol information at each layer.

What is the primary function of the Data Link Layer?

To ensure reliable transmission of data frames between directly connected nodes.

What is the difference between TCP and UDP?

TCP is connection-oriented and reliable; UDP is connectionless and faster but less reliable.

What does the Transport Layer do?

It ensures end-to-end communication, manages flow control, error detection, and data segmentation.

What are routing protocols used for?

Routing protocols determine how data gets to its destination and help make the routing process efficient.

Data Link Layer Sublayers

The Data Link Layer consists of two sublayers: LLC (Logical Link Control) and MAC (Media Access Control).

What is the main role of the Network Layer?

To route packets between different networks and manage logical addressing.

Framing in the Data Link Layer

Framing is when the Data Link Layer divides a stream of bits into manageable data units called frames.

What is the mnemonic device for remembering the OSI layers?

"Please Do Not Throw Sausage Pizza Away".

What is the function of the Application Layer?

The Application Layer provides network services directly to end-user applications.

Advantages of a Layered Model

Facilitates change, specializes design, reduces learning complexity, eases troubleshooting, and provides standards.

What is session management?

Session management involves establishing, maintaining, and terminating communication sessions between devices.

What does the Physical Layer define?

It defines the characteristics of the physical interface, the type of transmission medium and the representation of bits.