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'Bombe' Replica Code-Breaking WW2 Computer Was Used To Decipher Message Scrambled By An Enigma Machine (bbc.com)
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.
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.
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/...
At the end of the day, one of the team members who was a homosexual was given a cyanide pill.
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"
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.
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.
Not a bu-, a Bombe!
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.
"Gobbledygook" sounds like a new name for a new cipher suite :)
It was easy 70 years ago because there was always a 'Heil Hitler' at the end of each message, so it must be much easier today.
...this decrypter is the Bombe!
You should never set a bombe in a crib. The explosion will almost certainly wake the baby.
They achieved it before the war and constructed the first prototype of the bomb. Alan Turing gained this groundbreaking knowledge from them during his visit in Warsaw (just before the outbreak of war). He implemented the acquired solution using British technical resources and significantly reduced the computation time. https://www.warhistoryonline.c...