Bletchley Park and The WWII German Enigma cypher machines
Fifty miles (80km) north-west of London lies Bletchley Park. In 1883, it became home to the Leon family, whose patriach was a wealthy City of London financier. It was 1938 and the threat of war loomed as Hitler invaded first Austria and then Czechoslovakia. The Government Code and Cypher School, then based in London, needed a safer home where its intelligence work could carry on unhindered by enemy air attacks. At a junction of major road, rail and teleprinter connections to all parts of the country, Bletchley Park was eminently suitable. Commanded by Alastair Denniston, the Park was given the cover name Station X, being the tenth of a large number of sites acquired by MI6 for its wartime operations.
http://www.bletchleypark.org.uk/content/hist/history.rhtm
The Enigma machine is an electro-mechanical device that relies on a series of rotating 'wheels' or ‘rotors’ to scramble plaintext messages into incoherent ciphertext. The machine's variable elements can be set in many billions of combinations, and each one will generate a completely different ciphertext message. If you know how the machine has been set up, you can type the ciphertext back in and it will unscramble the message. If you don't know the Enigma setting, the message remains indecipherable.
The German authorities believed in the absolute security of the Enigma. However, with the help of Polish mathematicians who had managed to acquire a machine prior to the outbreak of WW2, British code breakers stationed at Bletchley Park managed to exploit weaknesses in the machine and how it was used and were able to crack the Enigma code.
Bletchley Park is near Milton Keynes and is wonderful to visit to learn where the German Enigma cyphers were decoded during WWII
The Bombe; Before the war started, the Poles passed all of their information on Enigma over to the Britain and France and two mathematicians working at Bletchley Park, Alan Turing and Gordon Welchman, were able to build on this research to develop the ‘Bombe’ machine. Turing and Welchman exploited the fact that enciphered German messages often contained common words or phrases, such as general’s names or weather reports and so were able to guess short parts of the original message. These guesses were called ‘cribs’. The fact that on an Enigma machine no letter can be enciphered as itself made guessing a small part of the text even easier. It also meant that the potential number of settings that the Enigma could be in on that day was greatly reduced.
Before running the Bombe, the wiring at the back of the machine was connected in accordance with a ‘menu’ drawn up by the code breakers based on cribs. The Bombe found potential Enigma settings not by proving a particular setting, but by disproving every incorrect one in turn.
Bletchley Park is near Milton Keynes and is wonderful to visit to learn where the German Enigma cyphers were decoded during WWII
The Lorenz was an even more complex cipher machine than Enigma. Made by the Lorenz company, it was used exclusively for the most important messages passed between the German Army Field marshals and their Central High Command in Berlin.
Tommy Flowers, a brilliant Post Office Electronics Engineer designed and build ‘Colossus’, using 1,500 thermionic valves (vacuum tubes). The first Colossus machine arrived at Bletchley in December 1943. This was the world’s first practical electronic digital computers
Lorenz had to be cracked by carrying out complex statistical analyses on the intercepted messages. Colossus could read paper tape at 5,000 characters per second and the paper tape in its wheels travelled at 30 miles per hour. This meant that the huge amount of mathematical work that needed to be done could be carried out in hours, rather than weeks.
Colossus at Bletchley Park is near Milton Keynes and is wonderful to visit to learn where the German Enigma cyphers were decoded during WWII
Colossus at Bletchley Park is near Milton Keynes and is wonderful to visit to learn where the German Enigma cyphers were decoded during WWII
Bletchley Park is near Milton Keynes and is wonderful to visit to learn where the German Enigma cyphers were decoded during WWII
Bletchley Park is near Milton Keynes and is wonderful to visit to learn where the German Enigma cyphers were decoded during WWII
Bletchley Park is near Milton Keynes and is wonderful to visit to learn where the German Enigma cyphers were decoded during WWII
Bletchley Park is near Milton Keynes and is wonderful to visit to learn where the German Enigma cyphers were decoded during WWII