(12/12) World War II Mind of a Code Breaker

World War II Videos
During the two years of the war, British cryptologists decoded German communications with limited success. Older codes, used for low security messages, were readily identified and broken by the Bletchley Park team. Some newer codes were broken mathematically, but decoding and translating these messages by hand proved an arduous task. By the time messages were fully understood, the information they contained was often outdated. Compounding the problem, these intercepts contained very little useful intelligence information. Since the mid-1930s, the German government had used complex cipher machines to disguise their most important communications.
The first great code breaking triumph at Bletchley Park came on August 30, 1941. A British "Y Station," one of the military listening stations that intercepted German communications, picked up a depth, a repeat transmission that used the same settings on the cipher machine. This intercept was forwarded to Bletchley Park. Cryptologists identified as "fish," the nickname for a message produced by the illusive Geheimschreiber cipher machine. Within two months, the Bletchley Park team broke the high-level German code.
To facilitate the processing of "fish" intercepts, Bletchley Park engineers borrowed an idea from plans the Polish intelligence service gave Britain before the war. They constructed a machine that aided the deciphering of intercepts, nicknamed a "bombe" because of the low, roaring noise it made while operating. The "bombe" constructed to decipher Geheimschreiber transmissions did help cryptographers to process intercepts more rapidly, but the machine required the exact synchronization of two paper tapes for printing. The tapes often broke, and the machine had to be reset. In addition, the start setting to process each intercept, the original cipher settings used by the Germans to send the message, had to be calculated by British cryptologists by hand. The process was still too complex to yield decoded intercepts ready for immediate translation to be useful to intelligence and military personnel.
Most of Germany's high-level military messages were encoded using a cipher machine called Enigma. The complex code used not only a cipher, but also an overlaying encryption to disguise the original text. The series of rotor wheels on the Enigma teleprinter gave the machine an extraordinary number of code combinations. The Germans were so confidant that the machine code was so nearly infinite in possibilities that it could never be broken. However, various intelligence services in neighboring nations had made considerable progress breaking Enigma even before the outbreak of the war. In Britain, efforts to break Enigma were known as Operation Ultra.
In the months preceding the German invasion of Poland in 1939, Polish intelligence passed on to British intelligence information on their efforts to break Enigma. Most helpful was the information Polish spies gathered on how the cipher machine operated, including sketches of the teleprinter and some of its components. With the information, Bletchley Park cryptologists found two key weak links in the Enigma code. Enigma code prohibited that any letter be encrypted as itself, and German standards of communication dictated that the same phrase begin all transmissions. Exploiting these two weaknesses, British cryptologists unraveled the Enigma code mathematically in late 1940.
Even though cryptologists could read portions of Enigma transmissions, they encountered the same delay of accessing intercepted information as they had with other codes. Another bombe was constructed that could process Enigma codes, expediting code breaking. However, cryptologists and engineers at Bletchley Park realized that another mechanical solution was needed to fully exploit German intercepts. To this end, two Bletchley Park engineers invented Colossus, the first electronic, programmable machine in 1943. Colossus not only decoded messages, but also broke through the overlaying cipher, producing a ready to translate copy of the intercept in the original German. With Colossus, Bletchley Park could decipher German communications before the intended recipients. Translated intercepts were immediately passed on to intelligence and military officials, making Bletchley Park central to the Allied war effort.

Category:

Education

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• World
• War
• II
• Enigma
• Bletchley
• Park
• British
• German
• Poland
• Polish
• Colossus
• Alan
• Turing

[LockCarge]

Good Documentary! Much better than the other inaccurate one. I've actually seen this before, as originally I think it was a BBC Timewatch episode, but maybe i'm mistaken.

Never-the-less, good video!

[2bn442RCT]

This was produced in USA for a PBS series tilted "Nova." I think it's so funny how the arrogant German Whermacht got burned by these people.

[stuartthegrant]

Very intresting films. All of them.

[2bn442RCT]

Yes my father who is Scottish enjoyed them very much and recorded them for me several years ago!

[postrea]

thanks for uploading this video....and thank you very much for all the people who had worked in Bletchley Park ...your work and your lives had been worthy for you had saved lives and you had shortened the war...may your souls rest in peace and happiness ....Winston Churchill and to the geniuses Charles Babbage, Alan Turing, Tommy Flowers...and to all who had died in the war

[rgbk73]

Yeah, just imagine working day and night for years just looking at code trying to make sense of it all. You could probably only dream about codes and text, with just the letters, lots of letters. At first not knowing why, then not knowing how and then not knowing when you'll break the code, with constant pressure to do your best. It must've been a strange experience.

[Wesley95501]

I just finish watching this video, now I'm going to watch the rise of the enigma too the minute I'm posting these comment.

[gulparviz]

:(....... weeping on the end documentary. thanks for the videos.

now i m gona watch [code breaker] the rise of enigma

[ms101289]

@mjeshaw thanks, i didn't understand all words acoustically, but knew i would like it

[monica20112]

My Mum worked with Tommy Flowers in the late 1930s. She was just a telephonist at Dollis Hill research station, but she never, EVER discussed what she did. She had to leave when she married - British policy then. If you got married, you left your job. How strange!

[Eurofighter19]

Superb documentary.

[km6xz]

@km6xz con't ....but seeing videos like this, and US school text books it appears that the average American has no idea that the USSR was even in the war, nor that John Wayne did not win it singlehandedly.

[km6xz]

@km6xz con't ....and Churchill had few bargaining chips. Besides neither country had the technology or manpower in uniform and trained to be able to mix it up with German at the time. Later in the war, both the USSR and USA certainly did, but that was after Germany had lost much of its strength. Some estimates put the military strength and readiness of Germany and its Axis Powers was down to 18% of what it had been by D-Day, most of that lost by having a 40 to 1 kill ratio on the E.F

[km6xz]

@washcloud I may have expressed poorly. The war was extended inadvertantly by the western Allies not sharing important intelligence and essentially waiting the USSR out while they wore down the Nazi's by attrition. If there was an equal effort, on 2-3 front 10s of millions of lives would have been spared. Roosevelt was in no position politically to bring the US into another war, the country was not solid behind Western Europe until Pearl Harbor.

[washcloud]

@km6xz I'm not quite sure I got the point you were trying to make, but if it was that USSR was the most important party of the combined forces that brought the Nazis to their knees, I do agree.

[km6xz]

@washcloud From the initial advantage in tactics and technology there really was no other outcome than Hitler overrunning Europe which he did with relative easy, and isolate England in what bubbles along as a sideshow for him, requiring limited resources, while the mass of his might was directed towards the Eastern Front. Films and popular notions project a much more dominate role of the western front than reality. 25,000,000 Soviet citizens died in that front, that also stopped Hitler