The most formidable weapon against errors of every kind is Reason - Thomas Paine
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Tunny machine is rebuilt at Bletchley Park
ON AUGUST 30, 1941, a German military teleprinter operator asked to retransmit a message to Vienna did so without changing the settings on his Lorenz S42 cipher machine. Worse, from a security point of view, he abbreviated the odd word, thus shifting all the letters in the rest of the message.
It was a fateful error that, thanks to an epic feat of deduction, changed the course of the Second World War and led to the birth of digital computing. The Lorenz machine, which the British called Tunny, is not as famous as the legendary Enigma machine that was cracked by Britain's Bletchley Park codebreakers, but it ought to be. It was more complex and gave a higher-level view because it was used to transmit messages from the Fuhrer to his generals in the field. Crack the Lorenz machine (pictured below) and you could eavesdrop on Hitler himself.
Bletchley Park guessed that the Lorenz cipher machine encrypted messages sent in standard five-bit binary teleprinter code by adding a masking stream, but it had no idea how this was generated. Sending two messages with the same settings was what codebreakers called a depth; by subtracting one message from the other you could separate out the masking. The codebreakers could spot a depth because at this stage in the war the Germans started each message with a 12-letter string that Bletchley Park rightly guessed gave the machine settings. The fact that the Vienna depth involved two nearly identical messages made it easier to crack and Bletchley managed to decrypt about 4,000 characters. But this would be little help deciphering other messages.
A chemistry graduate called Bill Tutte, drafted in from Cambridge because of his skill in solving puzzles, realized that more could be gleaned from that scrap of decrypted text - much more.
Astonishingly, in a two-month brainstorm he deduced the logical structure of the Lorentz, which used 12 twelve wheels with respectively 43, 47, 51, 53, 59, 37,61, 41, 31, 29, 26 and 23 positions. Two were motor wheels that spasmodically altered the position of the rest. Its rules for the binary addition were such that if you added the masking code at the receiving end you got the original message. This was done by giving the Lorentz receiving machine the same settings as the sending machine.
Even the most advanced Enigma machine had only four wheels with 26 positions, plus a 26-socket plug board.
Tags: Security
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Marvellous article and photo. The Tunny work and other breakthroughs at Bletchley Park shortened the war by at least two years and perhaps stopped the Americans nuking Berlin.
Time for me to revisit #bpark to see this new machine!
If things had been as clear cut as you imply, would there have been any need for Bletchley Park? Do yourself a favour - look up Alan Turing.
CODE HACKERS DIDNT WIN THE WAR, THE WAR WAS WON BY SOLDIERS WITH GUNS. THESE GUYS HELPED OUR SIDE GET SOME ADVANTAGE BY INTERCEPTING SOME OF HITLERS INSTRUCTIONS.
WAR IS ABHORRENT AND THE GOOD NEWS IS THESE FOLKS FIGURED OUT A WAY TO CONTRIBUTE AND KEEP THEIR HANDS CLEAN.
TODAY, WE ARE MAKING ROBOTS TO DO THE DIRTY WORK.
I do hope that they've been recognised by the crown for saving the realm?
Winnie made a most famous comment about the RAF that could also be aptly applied to your Bletchley Boffins. "...Never has so much been owed by so many to so few." What is even more astonishing is that the established military actually gave credance to this varied bunch.
They saved lives, not only British and Allied but Axis as well.
They also created moral conundrums that continue to plague the Intelligence community today. Of course I'm referring to Coventry. Even if it did not happen exactly as history says, there is a lesson there.
I find the whole of the Bletchley Park story extremely fascinating.
This article is about the breaking of the Tunny/Lorenz machine, which was more complex than the Enigma. Of course the Poles made a great contribution on Enigma, but it was only a start on what had to be done. That took a lot of brilliant people working throughout the war, and most of them (like the Poles) got nothing like the recognition they deserved because of the post-war secrecy about the project.
"In January 1940, the British cryptanalyst Alan Turing spent several days at PC Bruno conferring with his Polish colleagues. He had brought the Poles Zygalski sheets that had been produced at Bletchley Park by John Jeffreys using Polish-supplied information, but which were not working. It turned out that the wirings in Enigma rotors IV and V that Rejewski had worked out, had been copied down wrongly.[46] Correcting this error allowed the Poles to make, on 17 January 1940, the first break into wartime Enigma traffic—that from 28 October 1939.[47]" http://en.wikipedia.org/wiki/Biuro_Szyfr%C3%B3w
"The Poles' gift, to their western Allies, of Enigma decryption, five weeks before the outbreak of World War II, came not a moment too soon. Former Bletchley Park mathematician-cryptologist Gordon Welchman has written: "Ultra [the British Enigma-decryption operation] would never have gotten off the ground if we had not learned from the Poles, in the nick of time, the details both of the German military ... Enigma machine, and of the operating procedures that were in use."[34] After the war, Britain's Prime Minister Winston Churchill was to tell King George VI: "It was thanks to Ultra that we won the war."[35] Allied Supreme Commander Dwight D. Eisenhower, at war's end, described Enigma decryption as having been a "decisive contribution to the Allied war effort."[36]"
http://en.wikipedia.org/wiki/Biuro_Szyfr%C3%B3w
"legendary Enigma machine that was cracked by Britain's Bletchley Park codebreakers" - WHAT? Enigma was cracked by POLISH codebreakers before the WWII. You can find this information even on wikipedia: "n December 1932, the Polish Cipher Bureau first broke Germany's Enigma ciphers. Five weeks before the outbreak of World War II, on 25 July 1939, in Warsaw, the Polish Cipher Bureau gave Enigma-decryption techniques and equipment to French and British military intelligence.[3][4] Thanks to this,[5] during the war, allied codebreakers were able to decrypt a vast number of messages that had been enciphered using the Enigma. The intelligence gleaned from this source, codenamed "Ultra" by the British, was a substantial aid to the Allied war effort.[6]" http://en.wikipedia.org/wiki/Enigma_machine