STURGEON Cryptographic machine

Geheimschreiber

Although the ENIGMA remains the best know German cryptographic machine of World War II, in the early 1940's the German military introduced several new cryptographic teletypewriters known under the name Geheimschreiber - sometimes translated as "private secretary", sometimes as "secret writer".

These machines offered on-line encryption and decryption, that is plain test could be typed directly into the machine, automatically converted to encrypted text, and sent directly to the transmitter. In addtion to security, these "secret writers" provided the Germans with the ability to encrypt large volumes of test at high speed.

Learning that the Germans had named an early version of these machines SWORDFISH, the British and Americans bestowed nicknames associated with fish on the machines and the communications links in which they were used. The two most famous are TUNNY and STURGEON.

Just as they developed the Bombe to assist decryption of ENIGMA , the British developed data processing to attack the fish family of machine ciphers. (I must add: This was a whale of a job!) This led to the construction of the COLOSSUS which British historian F. H. Hinsley is "justly claimed as a pioneer programmable electronic digital computer."

STURGEON Siemens and Halske T52

The German Air Force began using the Siemens T-52 in 1942. The British nicknamed the machine STURGEON. Prototypes of this machine were developed at the request of the German Navy and were first manufactured in 1932.

Like the TUNNY machine, the STURGEON provided the German military with on-line cryptographic encryption decryption with high speed for large volumes of messages. The STURGEON added encryption capability to a standard teleprinter, although some models of STURGEON were later adapted for direct radio transmission.

Source: National Cryptologic Museum 13 February 2009 with some hyperlinks added

Interesting T52 link www.quadibloc.com/crypto/te0302.htm

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