Keynote Address: Herbert Yardley and the Japanese: Did Yardley Sell Secrets? (DadTheCool)

Herbert Yardley worked as a cipher clerk for the U.S. State Department starting in 1912, moved to MI-8 in 1917 and then the U.S. Cipher Bureau in 1919. After a decline in the amount of work during the 1920s, the Cipher Bureau in New York City closed in 1929, with all Army cryptanalysis moved to the Signal Corps. About this time, Yardley reportedly met with two Japanese officials at the Japanese Embassy in Washington. In his presentation, DadTheCool explores whether Yardley revealed US decryptions of enciphered communications sent by the Japanese Ministry of Foreign Affairs, in exchange for cash.

David Kahn Exhibit at National Cryptologic Museum (PHILLIES)

On January 23, 2024, the ACA and the cryptographic world lost a giant, David Kahn, who died at the age of 93. The former ACA President and Scholar-in-Residence at the NSA’s Center for Cryptologic History, donated many of his cryptographic tools and possessions to the National Cryptologic Museum. The Museum created a temporary exhibit honoring Kahn’s life, displaying Kahn’s possessions from April 29 – August 31, 2024. ACA Vice President PHILLIES had the pleasure of visiting the exhibit, and presents photos of the interesting items on display.

Elizebeth Smith Friedman: America’s First Female Cryptanalyst (WIRMZ)

In this historical retrospective, WIRMZ reveals the work done in obscurity by Elizebeth Smith Friedman, the wife of famed US Cryptanalyst William Friedman. WIRMZ discusses how Elizebeth Smith Friedman became involved in cryptanalysis, her support to William Friedman, research journals written in anonymity, and paints an amazing light on an incredible woman who provided unflagging support to the U.S. Government through her innovative techniques.

Ornamentals (H2O)

In this presentation, H2O describes various types of Ornamentals he has designed.

Risk Analysis of Submarine Cables in the Western Pacific (LANAKI)

Long-time ACA member LANAKI gives a thorough presentation detailing the locations of undersea cables in the Pacific Ocean, and China’s ownership of cables with the possibility of disruption to communications used by these cables. He provides a risk assessment of cables routed through various locations in the Pacific and their importance to the countries involved.

Encrypted Newspaper Ads in the 19th Century, and
Breaking Historical Ciphertexts with Modern Means (NOLA KAYE, CRYPTOBLOGGER, UNDA)

This doubleheader of talks provides an update on the Collinson ciphers first introduced at the 2023 ACA Convention. Our trio of speakers then discuss using hill climbing and other modern methods to attack old unknown cipher messages, with various rates of success.

Recovering K3 Keywords (DARING FLAIR)

ACA President DARING FLAIR presents a technique he uses to recover the keyword in K3 ciphers, providing a step-by-step example. He also shows how having a 13-letter shift in the plain and cipher alphabets can be advantageous as well as disadvantageous to the solver.

Dictionary Codes (PHILLIES)

This presentation discussed Harry Hantman, a fugitive who escaped from Washington, DC in 1973 and was on the lam until finally apprehended by US Marshals in 1993. Hantman communicated with his family using a dictionary code. ACA Vice President PHILLIES takes his 2018 presentation at the ACA Convention in Asheville, updating it with information revealed in a new book authored by the US Marshal who finally apprehended Hantman.