OSI Models

MAC

• Each network card has a MAC address as it is manufactured, thus unique.
• used in the local segment (LAN)

IP

• chosen by us.
• may be used to get to other segments.

Application

• How the applications access the network
• Web browsing, Email ,File transfers, ...

Presentation

• Data conversion and formatting
• File types(img, videos,...)

Sessions

• Creates a session between applications
• Session Control Protocol

Transport

• Transports data between endpoints
• TCP (segment), UDP (datagram)
• Break data into segments
• Uses port numbers

Network

• Adds network addresses
• Addres routing

Data Link

• Creates a logical link between devices'
• Adds local addresses
• Contains LLC (Logical Link Layer) and MAC (Media Access Control) sublayers

Physical

• Manages physical network components
• Encode data into physical signals