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Here is a list of past presentations at ICCH. The most recent presentation is at the top. Click on each listing to reveal more information below, including the speaker, presentation description and to access recordings.
Note: Effort has been made to ensure that the information on each presentation is accurate and up-to-date. To suggest a correction please contact the ICCH webmaster Patrick Hayes at .
Many old encryption methods are still hard to break today. For instance, cryptanalyzing a short 19th century Playfair cipher is far from trivial. WW2 Enigma messages, spy ciphers from the Cold War, and manual methods used by criminals such as the Zodiac Killer can also be challenging, especially when the ciphertexts are short. On the other hand, techniques for breaking historical ciphers have recently made considerable progress. Computer-based cryptanalysis methods such as hill climbing and simulated annealing have been successfully applied to break original WWII Enigma messages, as well as one of the world's most famous unsolved codes, a 1970 ciphertext sent by the Zodiac Killer. The record in solving short Playfair messages has improved: whereas many years ago the shortest Playfair ciphertext that could be cracked required a minimum of 60 letters, now messages as short as 26 letters have been solved. However, many other historical ciphertexts are still unbroken to date. This presentation will introduce the most important historical ciphers, and modern techniques to break them.
October 18, 2021
Here is a list of past presentations at ICCH. The most recent presentation is at the top. Click on each listing to reveal more information below, including the speaker, as well as the presentation date and description. Presentation recordings are available separately, in the ICCH Portal.
To view upcoming ICCH presentations, click here.
Note: Effort has been made to ensure that the information on each presentation is accurate and up-to-date. To suggest a correction please contact the ICCH webmaster Patrick Hayes at info@cryptologichistory.org.
Many old encryption methods are still hard to break today. For instance, cryptanalyzing a short 19th century Playfair cipher is far from trivial. WW2 Enigma messages, spy ciphers from the Cold War, and manual methods used by criminals such as the Zodiac Killer can also be challenging, especially when the ciphertexts are short. On the other hand, techniques for breaking historical ciphers have recently made considerable progress. Computer-based cryptanalysis methods such as hill climbing and simulated annealing have been successfully applied to break original WWII Enigma messages, as well as one of the world's most famous unsolved codes, a 1970 ciphertext sent by the Zodiac Killer. The record in solving short Playfair messages has improved: whereas many years ago the shortest Playfair ciphertext that could be cracked required a minimum of 60 letters, now messages as short as 26 letters have been solved. However, many other historical ciphertexts are still unbroken to date. This presentation will introduce the most important historical ciphers, and modern techniques to break them.
October 18, 2021
