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'Bombe' Replica Code-Breaking WW2 Computer Was Used To Decipher Message Scrambled By An Enigma Machine (bbc.com)

Posted by BeauHD on from the taste-of-the-past dept.

An anonymous reader quotes a report from the BBC: Computer historians have staged a re-enactment of World War Two code-cracking at Bletchley Park. A replica code-breaking computer called a Bombe was used to decipher a message scrambled by an Enigma machine. Held at the National Museum of Computing (TNMOC), the event honored Polish help with wartime code-cracking. Enigma machines were used extensively by the German army and navy during World War Two. This prompted a massive effort by the Allies to crack the complex method they employed to scramble messages. That effort was co-ordinated via Bletchley Park and resulted in the creation of the Bombe, said Paul Kellar who helps to keep a replica machine running at the museum. Renowned mathematician Alan Turing was instrumental in the creation of the original Bombe.

For its re-enactment, TNMOC recruited a team of 12 and used a replica Bombe that, until recently, had been on display at the Bletchley Park museum next door. The electro-mechanical Bombe was designed to discover which settings the German Enigma operators used to scramble their messages. As with World War Two messages, the TNMOC team began with a hint or educated guess about the content of the message, known as a "crib," which was used to set up the Bombe. The machine then cranked through the millions of possible combinations until it came to a "good stop," said Mr Kellar. This indicated that the Bombe had found key portions of the settings used to turn readable German into gobbledygook. After that, said Mr Kellar, it was just a matter of time before the 12-strong team cracked the message.

12 of 37 comments (clear)

  1. funny story by religionofpeas · · Score: 4, Interesting

    During WW2, the Ministry of Defence searched everywhere for cryptogramists (experts in code breaking), but accidentally hired a cryptogamist (expert in algae and other spore-distributing plants), Geoffrey Tandy, whose expertise turned out to be useful in restoring a water logged codebook.

    https://en.wikipedia.org/wiki/...

    1. Re:funny story by Dutch+Gun · · Score: 2

      If you're interested in stories related to codebreaking, Code Girls is a pretty entertaining and informative read. I've read lots of war-related accounts and biographies, but this one had a different flavor, being about war-related work on the homefront, and about codebreaking women, who were not given much if any credit for the work they did in this or other fields during the war.

      --
      Irony: Agile development has too much intertia to be abandoned now.
  2. For added authenticity by skoskav · · Score: 2, Insightful

    At the end of the day, one of the team members who was a homosexual was given a cyanide pill.

    1. Re:For added authenticity by gnasher719 · · Score: 2

      At the end of the day, one of the team members who was a homosexual was given a cyanide pill.

      At the end of the day, one of team members who was gay and forced to undergo "treatment" took a cyanide pill.

    2. Re: For added authenticity by Sultan+Of+Smut · · Score: 2

      Because his government hired him to help save the country which he did. That government then forced Turing to kill himself. They saw his earlier work as a separate issue too. Now save your breath if you were going to reply with taking issue with my use of the word "forced". It's too early in the morning for the "no one forced him to do it" rhetoric.

  3. Poland Developed the Bombe by Anonymous Coward · · Score: 2, Informative

    The Bombe was originally built by Polish crypt analysts using data given to them by the French. It was able to get the daily key used by the enigma machine, of the time, fairly quickly. When Poland was in danger of falling to the invading Nazi forces they sent a bombe and the results of their work to France and England. I assume they then destroyed any evidence of their accomplishment before the Nazis arrived. England, in the form of Alan Turing et al, then used this accomplishment to eventually develop a new machine that could extract the daily key from the newer, improved enigma machine.

    The name Bombe came from the shape of the Polish machine. It looked like a type of French dessert called a "Bombe"

    1. Re:Poland Developed the Bombe by hackertourist · · Score: 3, Informative

      using data given to them by the French

      AIU it was the other way round. The Polish team developed the codebreaking method using their own resources (notably, they were able to reconstruct the rotor wiring just by analyzing coded messages). They approached the French because they wanted to share their knowledge before the country was overrun. Also, changes made by the Germans meant the problem had become more complex and vastly more machines and personnel were needed to break the new codes with any regularity - resources the Polish cypher bureau didn't have.

    2. Re:Poland Developed the Bombe by Dutch+Gun · · Score: 2

      If I recall correctly, there were several phases in the bombe design. The original Polish codebreaking efforts, including their bombe, relied on some principles that turned out in the long run to be fragile and unsustainable. That was where Turing came in. He redesigned a British bombe on more general principles, and as such, was able to continue breaking messages when the Polish method stopped working due to changes in the encryption systems.

      The Polish definitely got the ball rolling, but Turing made many key breakthroughs, and the Americans helped later with their manufacturing prowess, which was required when a four-rotor Enigma was introduced that required much faster machines, and more of them. So, all three countries created their own bombe designs, and contributed to the codebreaking effort in their own capacity.

      I'm assuming what was demonstrated at Bletchley was one of the original British Turing-designed three-rotor-capable bombes, but the article didn't make that completely clear.

      --
      Irony: Agile development has too much intertia to be abandoned now.
  4. Bombes in Washington by jmcharry · · Score: 4, Informative

    What is seldom mentioned is that the British sent the design for the Bombe to the US where hundreds were built and did the bulk of the decrypting work. This is nicely presented at the NSA museum at Ft. Meade, which also has several Enigma machines, including a pre-war commercial version, and a section of a Bombe on display.

    1. Re:Bombes in Washington by hackertourist · · Score: 2

      I recently saw a documentary that referred to this as an early version of cloud computing: Bletchley Park sent intercepted messages and menus (Bombe settings) to the US via telegraph cables, where they were run and the results returned.

  5. Cosmology vs Cosmetology by Roger+W+Moore · · Score: 2

    There is a similar story about the cosmologist Werner Israel who appeared on a television show. Unfortunately, the interviewer had prepared lots of questions about lipstick, eyeshadow etc. because she thought he was an expert in cosmetology.

  6. Amazing place by hackertourist · · Score: 2

    It's quite remarkable these people were able to build a working replica, when all Bombes were destroyed after WW2 and its design kept secret. All they had to go on was people's recollections and the odd bit smuggled out here and there.
    And then they went and did the same for the Colossus.