Computer Networks — Topics

What a network actually is, and why almost every device around you is part of one.

Networks come in different sizes — from your own room to the entire planet.

The different shapes a network can be arranged in — and the trade-offs of each.

The physical (or invisible) paths that actually carry your data.

7 layers that describe how data travels across a network.

The simpler, 4-layer model that the real internet actually runs on.

Two models, one goal — here's exactly how they line up and differ.

How two devices agree to start a reliable connection.

How raw bits get organized into meaningful chunks, and how mistakes get caught.

Not just detecting an error — actually finding and fixing it.

The permanent hardware 'ID card' every network device carries, and how switches use it.

How a device figures out the MAC address behind a known IP address.

The unique 'postal address' every device needs to be found on a network.

Splitting one big network into smaller, organized pieces — with actual math you can follow.

The internet's successor addressing system — built to never run out of addresses.

How routers decide the best path for your data to travel.

The three protocols that actually keep the internet's traffic flowing correctly.

The two ways data actually travels across the Transport layer — reliable vs fast.

How TCP prevents a fast sender from overwhelming a slow receiver, or a busy network.

How one device juggles hundreds of network connections at once without mixing them up.

The internet's phonebook — turning easy-to-remember names into actual IP addresses.

The language your browser and every website actually speak to each other.

The three protocols working together every time you send or check email.

How your device automatically gets an IP address the moment it joins a network.

The two most common tools for controlling and protecting network traffic.

The math-based techniques that keep your data secret and verified, even over an open network.

The most common ways networks and the data flowing through them get attacked.

The physical hardware that actually builds a network, and what makes each one different.

How data travels through thin air, and what those confusing '802.11' numbers actually mean.

How networking concepts extend into the cloud — where the 'network' isn't physical hardware you own.