Virtual Lorenz

The Lorenz SZ40/42 cipher attachment

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Virtual Lorenz is an online Virtual simulation of the Lorenz SZ40, SZ42A and SZ42B - the range of teleprinter cipher attachment machine developed by C. Lorenz AG in Berlin during World War II.

The Lorenz was code named "Tunny" by Bletchley Park and it's workings were top secret. It was an amazing achievement that John Tiltman initially managed to retrieve a section of Lorenz key text from a duplicate message sent in error by the Germans while Bill Tutte took this data and successfully began the process of working out the entire structure of the cipher machine without ever seeing it!

Bill Tutte continued on to work out mathmatically how to decode the messages being sent and it was from this work that Tommy Flowers built the first computers, the Colossus, which helped break many messages for the remainder of the war.