** Note that the videos and related materials are for the personal use of ACA members. Please do not distribute without ACA permission. **

Events and Presentations

Morning Keynote Address (Jarl van Eycke)

In December 2020, David Oranchak, Sam Blake, and I solved the Zodiac 340 cipher. The cipher remained unsolved for 51 years despite receiving widespread attention. My 1 hour+ keynote will focus on some of the many insights that were made by researchers at the Zodiac Cipher Mailings & Discussion section of the Zodiackiller.net forum preluding our solve, with a deep dive into periodical transposition and sequential homophonic substitution.

Bifid Bookkeeping (SHMOO)

BIFIDs are not as hard as they look. A lot of what makes BIFID hard is the difficulties in bookkeeping. SHMOO’s “Easy BFID Worksheet Method” introduces a new worksheet which enables the various equalities of a BIFID to be visually and graphically tracked. As a bonus, it can be useful in key recovery. While not a complete method in itself, it can augment your regular solution schemes and, at its best, deliver you the full key square.

NSA Cryptanalytic Support to Law Enforcement (PHILLIES)

PHILLIES has been a long-time colleague of FBI cryptanalysts, lending his experience and expertise on many interesting cases. He will discuss his work involving a chessboard cryptosystem used by prisoners, a stalking case in Miami that used a variation of the Pig-Pen cipher, a calculator-based cryptosystem, and a double transposition cipher sent to a potential First Lady of the United States.

DNA Cryptography (TIGER’S EYE)

Iver Cooper, a retired biotech patent law attorney, will briefly discuss recreational DNA cryptography (like the MA2021 ornamental) and then examine the serious experimental work on the cryptographic and stenographic (message hiding) use of DNA “in silico” (codes and ciphers making use of DNA sequence databases), “in vitro” (DNA molecules encrypting messages and hidden like microdots), and “in vivo” (the message carrying DNAs are further hidden in living organisms).

Graffiti Cipher (EIDOLON)

Last spring, I discovered some artistic graffiti near some ruins in a forest. The graffiti contained what looked to be ciphertext. After failing to recover anything, I did some sleuthing online and was able to find the artist. They pointed me to some additional graffiti nearby with more ciphertext. I was able to break this and solve the whole system.

Famous and Not-So-Famous Unsolved Codes (NOLA KAYE, CRYPTOBLOGGER)

There are many other noteworthy unsolved ciphertexts that can be covered in a 45-minute talk, so in this next presentation, the two will introduce many more spectacular unsolved codes. The stories they tell include a mysterious 1953 murder case; a 32-page cryptogram from WW2; a series of encrypted inscriptions in Australia; a hidden treasure; and a mysterious message found in a secret pocket of a century-old dress. While some of these stories are well-known, others have little coverage in any academic literature or presentations. However, all of these stories have one thing in common: they include an encrypted message that has never been deciphered.

Bringing Ciphers to the Virtual K-12 School Community (MiB)

Science Olympiad Codebusters is an event for K-12 students to compete solving Aristocrats, Patristocrats, Xenocrypts, Baconian, Morbit and many other cipher types. In the event, teams of up to three students collaborate on solving ciphers. However, with the current pandemic, many events have switched to being fully virtual and we needed a tool to allow for the same level of collaboration to occur online that they can do on paper. To that end we have created a fully collaborative testing tool using Convergence.io that allows students in different locations to work together solving many of the ciphers that ACA members are used to solving. These tools have been designed to mimic the experience on paper while allowing the event supervisor to automatically score the tests and even check for potential cheating. During this session, we will demonstrate the tools and how the students use them.

Evening Keynote Address (A RICH ZIP CODE, Sam Blake)

Sam Blake will open the evening keynote with a focus on his quest to produce the hundreds of thousands of enumerations that eventually led us down the path to the correct solution. How did we find such a tiny needle in such a vast haystack? Then, A RICH ZIP CODE concludes the story. We have the long-sought solution to the 340, but there are still many mysteries and questions surrounding the Zodiac Killer and his ciphers. We will explore some of these mysteries.

Panel Discussion: “Collaborative Codebreaking” (DARING FLAIR, moderator)

Panel members include A RICH ZIP CODE, CRYPTOBLOGGER, NOLA KAYE, and PHILLIES, who will share their unique perspectives of teamwork in cryptanalysis.

Special Collaborative Codebreaking Event (DARING FLAIR)

At the conclusion of the 2021 Convention, the Krewe was presented with “Operation Creaky Wheel” – a collection of enciphered messages discovered at a presumed “dead drop” – and challenged to use teamwork, as well as their codebreaking savvy, to break them all within a 2-hour time limit! The convention attendees just barely accomplished this task. Care to give it a try yourself? Note: A slight update has been made to the scenario description and to Evidence Log Item #65 to correct errors found during the event.