4 lessons
What is a network, really?
Why computers need to talk to each other at all, and the one simple idea sitting underneath every network you have ever used.
Protocols and the layered model
Why network software is built like a set of nested envelopes, and how the OSI and TCP/IP models describe it.
Circuit switching, packet switching, and the virtual circuit compromise
A deeper look at the three ways to move data through a network, including the middle-ground idea most students forget: virtual circuits.
Bits, bytes, and how devices get addresses
A gentle path from counting on your fingers to binary numbers, and why every device needs both a MAC address and an IP address.