Computer Networks

Layers, TCP/IP and what happens on a request.

Computer Networks is taught here in 3 lessons, running from Layered models and TCP/IP through to One page request, end to end. Each lesson takes one topic, shows the working code, and links onward to the next, so the course can be read straight through in order.

TrackComputer Science Fundamentals
Lessons3
LevelBeginner
Reading timeabout 39 minutes
PrerequisitesHelpful, but not required: Data Structures

Lessons

  1. Layered models and TCP/IPHow the OSI and TCP/IP models split network work into layers, and why encapsulation is the idea that lets every level be replaced independently.
  2. HTTP and DNS in practiceName resolution from stub resolver to authoritative server, the record types that matter, and how HTTP/1.1, HTTP/2 and HTTP/3 differ on the wire.
  3. One page request, end to endThe full path from typing a URL to a rendered page: DNS, TCP, TLS, HTTP, subresources, and where the milliseconds actually go.

More in Computer Science Fundamentals

Algorithms Data Structures Operating Systems Character Encodings Hashing & Checksums Data Formats Dates & Time Regular Expressions

FAQ

How long does the Computer Networks course take?
It has 3 lessons, about 39 minutes of reading. Expect roughly twice that if you type out and run every example.
Do I need prior experience for Computer Networks?
Not strictly. It helps to have read Data Structures first, because some lessons build on it, but every lesson explains its own assumptions.
What should I read after Computer Networks?
Continue with Operating Systems (3 lessons), the next course in Computer Science Fundamentals.

Last refreshed 2026-09-18.