The Workings of the Internet or: How Censors Block You From Websites

"The Internet is a big network of computers all over the world connected to each other" - most of us have probably come across an explanation such as this when trying to learn how it all works. However, this does not explain anything at a technical level – what is really happening when you type “google.com” in your browser and hit enter?

Why does “google.com” work, but some, ahem, other websites get blocked? How? Can the person sitting next to you in a coffee shop really steal all your data unless you use “CompanyVPN”? (Don’t forget to use code TOR_OR_BUST for 1337% off!)

There is a lot that goes into making the internet work, and there are a lot of (mostly legitimate) parties between you and the website you’re visiting. Understanding how it all works is key to understanding how this system is (ab)used to perform surveillance, block access, and steal data.

This talk aims to first explain some basic concepts of how two parties can communicate over the internet via “packets”, analogous to postcards (ever sent those?!). Through this analogy, we’ll learn exactly who sits in the middle, what can they see and can they change. You'll come to appreciate how brittle parts of Internet infrastructure can be, the number of parties that need to cooperate across the world, and maybe end up surprised that any of it works at all.

We’ll also explore how bad actors can tamper with the “Postcards” - explaining how censors work, or how information is leaked, even in 2026 with all the decades of improvements since the 80s. By the end, you’ll either be surprised to learn how private the internet is by default, or end up annoyed at how some stuff still gets out! And of course, you will start judging the predatory VPN advertising more harshly.