OSI Reference Model – Easy way to remember




Application Layer: End user processes like file transfer, e-mail, network software services. E.g. Telnet, FTP


Presentation/Syntax Layer: Format, Encrypt data to send across network.


Session Layer: Establishes, manages and terminates connections between applications .


Transport Layer: End-to-end error recovery, flow control.


Network Layer: Switching, Routing, Addressing, internetworking, error handling, congestion control and packet sequencing.


Data Link Layer: Encoding, decoding data packets into bits.

Media Access Control Sub-layer: Data access/transmit permissions.

Logical Link Sub-layer: Frame synchronization, flow control, error checking.


Physical Layer: Conveys the bit stream (electrical, light, radio)

E.g. Ethernet, RS232, ATM


An easy way to remember : use the following quotes

“All People Seem To Need Data Processing”

“People Do Not Trust Sales People Always”