Secret Services & Patents: The Enigma Machine

The patent I chose to represent my blog is the one about the Enigma Machine, because in the field of Cryptography is the first form of mechanization of this long process of encrypting messages, for its internal complexity, involving both mechanical and electronic circuits, that makes it a real artwork. The images below are taken from the first Enigma-related Patent, the one presented by Arthur Scherbius the 23 February 1918 and released the 8 July 1925.

 

 Later in time other patents were filed, most of them proposing implementations to the original machine: for example the possibility to use tubes fulfilled with water instead of electric wires, or to change the letter circuit with a multi-switches pannel (number of possible swaps incresing in time from 6 to 10), to remove rotors and  trade their places (UKW), to add a ring that make the rotor, on which it is applied, to do an additional movement after a key-press....

There are also two evolutions of the machine: the Enigma A and the Zahlwerk Enigma (or Enigma G), respectively filed on March, 26th, 1924 and on November, 9th, 1928. There were more developpements of the machine depending on the branch of the German army in which it was used.





Following: a family tree of the Enigma evolution created by Paul Reuvers & Frode Weierud (second link between sources for further informations) and here on the right the legend to better understand how it has been organized by the autors.
Enjoy...

Continues....

Sources:
http://www.cryptomuseum.com/crypto/enigma/patents/
http://www.cryptomuseum.com/crypto/enigma/tree.htm