The Bits and Bytes of Computer Networking

The TCP/IP Five-Layer Network Model

# Layer Name Protocol Data Unit Adressing
5 Application HTTP, SMTP, etc.. Messages
4 Transport TCP/UDP Segment Port #'s
3 Network IP Datagram IP address
2 Data Link Ethernet, Wi-Fi Frames MAC Address
1 Physical 10 Base T, 802.11 Bits

Physical Layer

Data Link Layer

Network Layer

IP Addresses

Subnetting

Transport Layer

Application Layer

Further References