Enigma-A

The Enigma-A (also written Enigma A and also called "The Small Military Machine" ) is an early model of the Enigma rotor key machine and at the same time the first so-called "incandescent lamp cipher machine " .

history

A reversing roller (similar to the VHF B used in later models in the picture) is used for the first time on the Enigma A.

In the long history of the different Enigma models , the Enigma-A, introduced in 1924, was the third model chronologically (see also: family tree of the Enigma under web links ). In contrast to its two forerunners, the “writing Enigma cipher machines”, namely the so-called “ trading machine” from 1923 and the “ writing Enigma ” from 1924, it was the first to use light bulbs for output rather than type levers . This made it possible for the first time to make the machine much lighter, more compact and more manageable than the comparatively bulky and difficult to transport previous models. The Enigma-A was thus the first of the later so successful "incandescent lamp cipher machines " and with only 500 ℛℳ also significantly cheaper than the comparatively expensive trading machine  (approx. 8000 ℛℳ).

To operate the light bulbs, the Enigma-A contained a built-in 4.5 volt battery . In contrast to its predecessors and also its successors, it had a cryptographic heart of only three rotating rollers (also known as rotors), of which only two were through-going rotors. The reverse cylinder (VHF) appeared for the first time as a cryptographic innovation , an invention by Willi Korn (see also: Enigma patents ), an employee of the Chiffriermaschinen-Aktiengesellschaft (ChiMaAG), i.e. the factory that opened on July 9, 1923 in Berlin ( W 35 , Steglitzerstr. 2, today Pohlstrasse , Berlin-Tiergarten ) and in which the Enigma was developed and manufactured.

What is striking about the Enigma-A is the arrangement of the 26 keys and lamps in only two (instead of three) rows in the following way:

 A   B   C   D   E   F   G   H   I   J   K   L   M
 N   O   P   Q   R   S   T   U   V   W   X   Y   Z

The weight and dimensions (L × W × H) were about 5 kg and 270 mm × 230 mm × 130 mm, respectively. No surviving copy is known.

literature

• Anders Wik: The First Classical Enigmas - Swedish Views on Enigma Development 1924–1930. Proceedings of the 1st International Conference on Historical Cryptology, PDF; 12.5 MB 2018, pp. 83-88.

Web links

• Electric key cipher. German patent DE407804, January 18, 1924, PDF
• "Enigma A" bulb cipher, accessed on February 20, 2019.
• Enigma A in the Crypto Museum (English) accessed on February 20, 2019.
• Enigma Family Tree . Enigma Family Tree, accessed February 20, 2019.

Individual evidence

1. ↑ "Enigma A" bulb cipher, accessed on February 20, 2019.
2. ↑ Enigma A in the Crypto Museum (English) accessed February 20, 2019.
3. ↑ Louis Kruh, Cipher Deavours: The commercial Enigma - Beginnings of machine cryptography . In: Cryptologia , Rose-Hulman Institute of Technology, Taylor & Francis, Philadelphia PA 26.2002,1 (January), p. 2. ISSN  0161-1194 apprendre-en-ligne.net (PDF; 0.8 MB) accessed 3. March 2016.
4. ↑ Enigma A in the Crypto Museum (English) accessed on February 20, 2019.