TCP/IP stack

Function of Application Layer

Function of Application Layer

Connect user and apps (services)

Application Layer Protocols

HTTP (80), HTTPS (443), SSH (23), DNS (53), DHCP (67/68)

Application Layer Data Unit

Data, Messages

Application Layer address

N/A

Application Layer Hardware

N/A

Application Layer Commands

nslookup, tasklist

Transport Layer Function

Connects processes

Transport Layer Protocols

TCP, UDP, NAT

Transport Layer Data Unit

Segments, Datagrams

Transport Layer Address

Port Number

Transport Layer Hardware

N/A

Transport Layer Commands

netstat, -ano

Network Layer Function

Connects Networks

Network Layer Protocols

IP, IMCP

Network Layer Data Unit

Packets

Network Layer Address

IPv4, IPv6

Network Layer Hardware

Routers

Network Layer Commands

ping, tracert

Data Link Layer Function

Connects to local network

Data Link Layer Protocol

Ethernet (802.3), Wi-Fi (802.11), LTE/5G

Data Link Layer Unit

Frames

Data Link Layer Address

MAC Address

Data Link Layer Hardware

Switches

Data Link Layer Command

ipconfig /all, arp -a

Physical Layer Function

Connects devices

Physical Layer Protocols

Voltages, RF Signals

Physical Layer Data Unit

Bits, Bytes

Physical Layer Address

N/A

Physical Layer Hardware

Wires, Airwaves, Hubs

Physical Layer Command

N/A