Crypto 101

Date: 2025-02-05

Difficulty: Beginner

Delivered By: Dan Hoang

Overview

We all know encryption is important, but just as important as having encryption is having good encryption. This session introduces some basic encryption techniques and methods to break them. Specifically, we'll cover:

• Early examples of text ciphers
• Substitution ciphers and frequency analysis
• Ciphers from the beginning of computer science

Prerequisites

• CyberChef, as usual.
• decode.fr has several useful tools including identifying cipher algorithms, frequency analysis and lots of encoders/decoders.

Session Link

The challenges are available at https://crypto-101.sucss.org/.