LEARNING CLASSICAL & MODERN CRYPTOGRAPHY
RULES & REGULATIONS
When it comes to cipher-breaking, there are only three rules:
NEVER give up
Have fun :-)
But we have some more rules for this particular competition. There will be prizes, but you should know how prizes will be distributed and whether you are eligible to win one. Also, learn how points are awarded.
There are 10 challenges; one will be released each week. Part A Challenges are the easiest and they will almost always have hints. Part B Challenges may also have hints, but they will be vaguer -- examples of possible hints for a Part B Challenge include images, audio files, terrible poetry, and really terrible puns. Part C Challenges are the toughest because they require true cryptanalysis skills (no hints).
If you are new to cryptography, don't worry! We have made some screencast tutorials on basic codebreaking, with sample challenges. There is even a Cryptanalysis Guide that you should check out. Finally, feel free to help yourself to any online or personal tools that you want to use to crack the challenges. We have posted links to resources and programs under Tools.
The Cryptanalysis Guide
This is a guide to cryptanalysis for new and experienced cryptographers alike. It is also helpful to refer to when you are unsure of how to recognize or break a certain type of cipher. Included in the guide are references to suggested programs in Tools that can be used to decrypt each type of cipher. Also included are reference graphs and tables such as English single-letter frequencies, most common English bigrams, trigrams, etc.
This challenge was organized by the Gunn Cryptology Club. We attend Henry M. Gunn High School in Palo Alto, CA and are very interested in cryptography (as you can see). This cipher challenge took inspiration from the 2019 National Cipher Challenge, which we took part in. Our primary reasons for organizing this challenge are to provide a way for middle and high school students to develop an interest in a field that most of them have never even heard about. Cryptography is very relevant today in the modern world as it becomes increasingly harder for large companies to keep their data secure. This challenge offers a taste at breaking ciphers. It aims to show the young generation how easily our "secret" messages can be cracked. Our end goal is to inspire the younger generation and educate them in the foundations of classical and modern cryptography using a fun, yet competitive approach.