Cryptanalysis of the Enigma bombes were, however, very fast and the most successful. They were extensively used by Bletchley Park over teleprinter links (using the Combined Cipher Machine) to OP-20-G for both 3-rotor and 4-rotor jobs. Although the German army, SS, police, and railway all used Enigma with similar procedures, it was the "Luftwaffe" (Air Force) that was the first and most fruitful source of Ultra intelligence during the war. The messages were decrypted in Hut 6 at Bletchley Park and turned into intelligence reports in Hut 3. The network code-named ‘Red’ at Bletchley Park was broken regularly and quickly from 22 May 1940
Cryptanalysis of the Enigma death in February 1943, was the solving, in 1941, of the "Abwehr" Enigma. Intercepts of traffic which had an 8-letter indicator sequence before the usual 5-letter groups led to the suspicion that a 4-rotor machine was being used. The assumption was correctly made that the indicator consisted of a 4-letter message key enciphered twice. The machine itself was similar to a Model G Enigma, with three conventional rotors, though it did not have a plug board. The principal difference to the model G was that it was equipped with a reflector that was advanced by the stepping mechanism once it