New Images of Colossus Released
GCHQ has released new images of the WWII Colossus code-breaking computer, celebrating the machine’s eightieth anniversary (birthday?).
News article.
Entries Tagged "history of cryptography"
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Mary Queen of Scots Letters Decrypted
This is a neat piece of historical research.
The team of computer scientist George Lasry, pianist Norbert Biermann and astrophysicist Satoshi Tomokiyo—all keen cryptographers—initially thought the batch of encoded documents related to Italy, because that was how they were filed at the Bibliothèque Nationale de France.
However, they quickly realised the letters were in French. Many verb and adjectival forms being feminine, regular mention of captivity, and recurring names—such as Walsingham—all put them on the trail of Mary. Sir Francis Walsingham was Queen Elizabeth’s spymaster.
The code was a simple replacement system in which symbols stand either for letters, or for common words and names. But it would still have taken centuries to crunch all the possibilities, so the team used an algorithm that homed in on likely solutions.
EDITED TO ADD (2/13): More news.
Charles V of Spain Secret Code Cracked
Diplomatic code cracked after 500 years:
In painstaking work backed by computers, Pierrot found “distinct families” of about 120 symbols used by Charles V. “Whole words are encrypted with a single symbol” and the emperor replaced vowels coming after consonants with marks, she said, an inspiration probably coming from Arabic.
In another obstacle, he used meaningless symbols to mislead any adversary trying to decipher the message.
The breakthrough came in June when Pierrot managed to make out a phrase in the letter, and the team then cracked the code with the help of Camille Desenclos, a historian. “It was painstaking and long work but there was really a breakthrough that happened in one day, where all of a sudden we had the right hypothesis,” she said.
Gus Simmons’s Memoir
Gus Simmons is an early pioneer in cryptography and computer security. I know him best for his work on authentication and covert channels, specifically as related to nuclear treaty verification. His work is cited extensively in Applied Cryptography.
He has written a memoir of growing up dirt-poor in 1930s rural West Virginia. I’m in the middle of reading it, and it’s fascinating.
History of the HX-63 Rotor Machine
Jon D. Paul has written the fascinating story of the HX-63, a super-complicated electromechanical rotor cipher machine made by Crypto AG.
More Military Cryptanalytics, Part III
Late last year, the NSA declassified and released a redacted version of Lambros D. Callimahos’s Military Cryptanalytics, Part III. We just got most of the index. It’s hard to believe that there are any real secrets left in this 44-year-old volume.
Newly Declassified NSA Document on Cryptography in the 1970s
This is a newly unclassified NSA history of its reaction to academic cryptography in the 1970s: “NSA Comes Out of the Closet: The Debate over Public Cryptography in the Inman Era,” Cryptographic Quarterly, Spring 1996, author still classified.
The Story of Colossus
Nice video of a talk by Chris Shore on the history of Colossus.
Military Cryptanalytics, Part III
The NSA has just declassified and released a redacted version of Military Cryptanalytics, Part III, by Lambros D. Callimahos, October 1977.
Parts I and II, by Lambros D. Callimahos and William F. Friedman, were released decades ago—I believe repeatedly, in increasingly unredacted form—and published by the late Wayne Griswold Barker’s Agean Park Press. I own them in hardcover.
Like Parts I and II, Part III is primarily concerned with pre-computer ciphers. At this point, the document only has historical interest. If there is any lesson for today, it’s that modern cryptanalysis is possible primarily because people make mistakes
The monograph took a while to become public. The cover page says that the initial FOIA request was made in July 2012: eight and a half years ago.
And there’s more books to come. Page 1 starts off:
This text constitutes the third of six basic texts on the science of cryptanalytics. The first two texts together have covered most of the necessary fundamentals of cryptanalytics; this and the remaining three texts will be devoted to more specialized and more advanced aspects of the science.
Presumably, volumes IV, V, and VI are still hidden inside the classified libraries of the NSA.
And from page ii:
Chapters IV-XI are revisions of seven of my monographs in the NSA Technical Literature Series, viz: Monograph No. 19, “The Cryptanalysis of Ciphertext and Plaintext Autokey Systems”; Monograph No. 20, “The Analysis of Systems Employing Long or Continuous Keys”; Monograph No. 21, “The Analysis of Cylindrical Cipher Devices and Strip Cipher Systems”; Monograph No. 22, “The Analysis of Systems Employing Geared Disk Cryptomechanisms”; Monograph No.23, “Fundamentals of Key Analysis”; Monograph No. 15, “An Introduction to Teleprinter Key Analysis”; and Monograph No. 18, “Ars Conjectandi: The Fundamentals of Cryptodiagnosis.”
This points to a whole series of still-classified monographs whose titles we do not even know.
EDITED TO ADD: I have been informed by a reliable source that Parts 4 through 6 were never completed. There may be fragments and notes, but no finished works.
Sidebar photo of Bruce Schneier by Joe MacInnis.