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Genevieve Grotjan unraveled enemy codes during World War II (2018)

44 points by Hooke 7y ago

Taniwha 7y ago
This is a great read ..... We hear a lot about smart Allied code breakers breaking German and Japanese code - anyone know what the Allies' codes were like? were they broken?
- willvarfar 7y ago
  The biggest thing hindering the Germans was organizational - they had lots of units that competed with each other. A good list of their success https://en.wikipedia.org/wiki/German_code_breaking_in_World_War_II https://en.wikipedia.org/wiki/German_code_breaking_in_World_... The Germans weren't the only ones with internal division sapping effectiveness; on the eve of Pearl Harbor the US managed to crack the Japanese diplomatic cipher. However, two teams, nominally organised and housed together but still vying with one another, tried to own it exclusively. To keep things fair, the navy team and the army team took turns cracking it. There was a lot of heat about who knew what when later. As the Germans approached Moscow, the British Embassy evacuated. Years later, a bug was discovered cemented into the roof of the cipher room, presumed to have been planted while the embassy was evacuated. So clearly, despite the present danger on the outskirts, some people in Moscow were thinking of the future wars... My notes on who broke Enigma when and where https://williame.github.io/post/145745642718.html https://williame.github.io/post/145745642718.html Someone who doesn't get as much attention as Alan Turing and Gordon Welchman is W. T. Tutte. His feat of breaking the Fish cipher is perhaps the greatest mental gymnastics ever? An unsung hero during this period was Arne Beurling in Sweden. I came across the T52 in a museum in Stockholm and was completely surprised. Its a variant of the Fish cipher and the Arne broke it just like Tutte did in England. I'd have to look it up but perhaps Arne was first? Amazing too. https://en.wikipedia.org/wiki/Arne_Beurling https://en.wikipedia.org/wiki/Arne_Beurling I'd love to hear about things I've missed!
  - raxxorrax 7y ago
    Neat summary. I wonder how many encrypted texts they actually got to be able to come up with a decryption technique. Cannot imagine it being too many.
- jjtheblunt 7y ago
  One example is https://en.wikipedia.org/wiki/Code_talker https://en.wikipedia.org/wiki/Code_talker
- Isamu 7y ago
  SIGSALY was an unbreakable voice scrambler that relied on early digital techniques, pretty interesting: https://spectrum.ieee.org/geek-life/hands-on/rebuilding-a-piece-of-the-first-digital-voice-scrambler https://spectrum.ieee.org/geek-life/hands-on/rebuilding-a-pi... IIRC, it was unbreakable because it amounted to a one-time-pad that was shared between the transmitter and receiver.
melling 7y ago
A couple of highly rated books mentioned in the article: Code Girls: https://www.amazon.com/Code-Girls-Untold-American-Breakers/dp/0316439894/ref=nodl_ https://www.amazon.com/Code-Girls-Untold-American-Breakers/d... The Woman Who Smashed Codes: https://www.amazon.com/Woman-Who-Smashed-Codes-Outwitted/dp/0062430483/ref=nodl_ https://www.amazon.com/Woman-Who-Smashed-Codes-Outwitted/dp/...
- Moshe_Cohen 7y ago
  I'm curious what kind of person could see titles like those without groaning.
  - melling 7y ago
    I think publishers make authors do that. I wouldn’t read this book for years because of the silly title: “You Can Be a Stock Market Genius" https://www.amazon.com/You-Can-Stock-Market-Genius/dp/0684840073/ref=nodl_ https://www.amazon.com/You-Can-Stock-Market-Genius/dp/068484...
    - bryanrasmussen 7y ago
      So I take it you did read it finally? What did it do for you?
      - melling 7y ago
        I kept seeing the author mentioned. He’s a famous value investor. https://en.wikipedia.org/wiki/Joel_Greenblatt https://en.wikipedia.org/wiki/Joel_Greenblatt “ In 1985, Greenblatt started a hedge fund, Gotham Capital, with $7 million, most of which was provided by junk-bond king Michael Milken.[4] Robert Goldstein joined Gotham Capital in 1989.[1] Through his firm Gotham Capital, Greenblatt presided over an annualized return of 50% ("after all expenses" but "before general partner's incentive allocation" fees) or 30% (net of fees[5]) from 1985 to 1994 by investing in ""special situations" like spinoffs and other corporate restructurings".[6][7] In January 1995 Gotham returned all capital of outside partners (approximately $500 million).”
_n_b_ 7y ago
This article also led me to this very cool summary of how the PURPLE code actually worked: https://cryptocellar.org/pubs/PurpleRevealed.pdf https://cryptocellar.org/pubs/PurpleRevealed.pdf

44 points by Hooke 7y ago

This is a great read ..... We hear a lot about smart Allied code breakers breaking German and Japanese code - anyone know what the Allies' codes were like? were they broken?

willvarfar 7y ago
The biggest thing hindering the Germans was organizational - they had lots of units that competed with each other. A good list of their success https://en.wikipedia.org/wiki/German_code_breaking_in_World_War_II https://en.wikipedia.org/wiki/German_code_breaking_in_World_... The Germans weren't the only ones with internal division sapping effectiveness; on the eve of Pearl Harbor the US managed to crack the Japanese diplomatic cipher. However, two teams, nominally organised and housed together but still vying with one another, tried to own it exclusively. To keep things fair, the navy team and the army team took turns cracking it. There was a lot of heat about who knew what when later. As the Germans approached Moscow, the British Embassy evacuated. Years later, a bug was discovered cemented into the roof of the cipher room, presumed to have been planted while the embassy was evacuated. So clearly, despite the present danger on the outskirts, some people in Moscow were thinking of the future wars... My notes on who broke Enigma when and where https://williame.github.io/post/145745642718.html https://williame.github.io/post/145745642718.html Someone who doesn't get as much attention as Alan Turing and Gordon Welchman is W. T. Tutte. His feat of breaking the Fish cipher is perhaps the greatest mental gymnastics ever? An unsung hero during this period was Arne Beurling in Sweden. I came across the T52 in a museum in Stockholm and was completely surprised. Its a variant of the Fish cipher and the Arne broke it just like Tutte did in England. I'd have to look it up but perhaps Arne was first? Amazing too. https://en.wikipedia.org/wiki/Arne_Beurling https://en.wikipedia.org/wiki/Arne_Beurling I'd love to hear about things I've missed!
- raxxorrax 7y ago
  Neat summary. I wonder how many encrypted texts they actually got to be able to come up with a decryption technique. Cannot imagine it being too many.
jjtheblunt 7y ago
One example is https://en.wikipedia.org/wiki/Code_talker https://en.wikipedia.org/wiki/Code_talker
Isamu 7y ago
SIGSALY was an unbreakable voice scrambler that relied on early digital techniques, pretty interesting: https://spectrum.ieee.org/geek-life/hands-on/rebuilding-a-piece-of-the-first-digital-voice-scrambler https://spectrum.ieee.org/geek-life/hands-on/rebuilding-a-pi... IIRC, it was unbreakable because it amounted to a one-time-pad that was shared between the transmitter and receiver.

melling 7y ago

A couple of highly rated books mentioned in the article: Code Girls: https://www.amazon.com/Code-Girls-Untold-American-Breakers/dp/0316439894/ref=nodl_ https://www.amazon.com/Code-Girls-Untold-American-Breakers/d... The Woman Who Smashed Codes: https://www.amazon.com/Woman-Who-Smashed-Codes-Outwitted/dp/0062430483/ref=nodl_ https://www.amazon.com/Woman-Who-Smashed-Codes-Outwitted/dp/...

Moshe_Cohen 7y ago
I'm curious what kind of person could see titles like those without groaning.
- melling 7y ago
  I think publishers make authors do that. I wouldn’t read this book for years because of the silly title: “You Can Be a Stock Market Genius" https://www.amazon.com/You-Can-Stock-Market-Genius/dp/0684840073/ref=nodl_ https://www.amazon.com/You-Can-Stock-Market-Genius/dp/068484...
  - bryanrasmussen 7y ago
    So I take it you did read it finally? What did it do for you?
    - melling 7y ago
      I kept seeing the author mentioned. He’s a famous value investor. https://en.wikipedia.org/wiki/Joel_Greenblatt https://en.wikipedia.org/wiki/Joel_Greenblatt “ In 1985, Greenblatt started a hedge fund, Gotham Capital, with $7 million, most of which was provided by junk-bond king Michael Milken.[4] Robert Goldstein joined Gotham Capital in 1989.[1] Through his firm Gotham Capital, Greenblatt presided over an annualized return of 50% ("after all expenses" but "before general partner's incentive allocation" fees) or 30% (net of fees[5]) from 1985 to 1994 by investing in ""special situations" like spinoffs and other corporate restructurings".[6][7] In January 1995 Gotham returned all capital of outside partners (approximately $500 million).”

_n_b_ 7y ago

This article also led me to this very cool summary of how the PURPLE code actually worked: https://cryptocellar.org/pubs/PurpleRevealed.pdf https://cryptocellar.org/pubs/PurpleRevealed.pdf