In the
history of cryptography, the NEMA (NEue MAschine)
("new machine"), also designated the T-D (Tasten-Druecker-Maschine) ("key-stroke machine"), was a 10-wheel
rotor machine designed by the
Swiss Army
The Swiss Armed Forces (german: Schweizer Armee, french: Armée suisse, it, Esercito svizzero, rm, Armada svizra; ) operates on land and in the air, serving as the primary armed forces of Switzerland. Under the country's militia system, re ...
during the
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
as a replacement for their
Enigma machines.
History
The Swiss became aware that their current machine, a commercial Enigma (the Swiss K), had been broken by both Allied and German
cryptanalysts.
A new design was begun between 1941 and 1943 by Captain Arthur Alder, a professor of
mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...
at the
University of Bern
The University of Bern (german: Universität Bern, french: Université de Berne, la, Universitas Bernensis) is a university in the Switzerland, Swiss capital of Bern and was founded in 1834. It is regulated and financed by the Canton of Bern. It ...
. The team which designed the machine also included Professors
Hugo Hadwiger
Hugo Hadwiger (23 December 1908 in Karlsruhe, Germany – 29 October 1981 in Bern, Switzerland) was a Swiss mathematician, known for his work in geometry, combinatorics, and cryptography.
Biography
Although born in Karlsruhe, Germany, Hadwige ...
and
Heinrich Emil Weber Heinrich may refer to:
People
* Heinrich (given name), a given name (including a list of people with the name)
* Heinrich (surname), a surname (including a list of people with the name)
*Hetty (given name), a given name (including a list of peo ...
.
[ :de:Heinrich Emil Weber]
In the spring of 1944, the first prototype had become available. After some modifications, the design was accepted in March 1945, and production of 640 machines began the following month by Zellweger AG. The first machine entered service in 1947.
NEMA was declassified on 9 July 1992, and machines were offered for sale to the public on 4 May 1994.
File:NEMA-IMG 0522.jpg, The NEMA machine was a Swiss
Swiss may refer to:
* the adjectival form of Switzerland
* Swiss people
Places
* Swiss, Missouri
* Swiss, North Carolina
*Swiss, West Virginia
* Swiss, Wisconsin
Other uses
*Swiss-system tournament, in various games and sports
*Swiss Internation ...
rotor machine, designed to replace commercial Enigma machines.
File:Cover-open-1000.jpg, NEMA uses 10 wheels, of which one is a reflector, four are normal rotors, and the remaining five are "Drive wheels", which control the stepping of the rotors and the reflector.
The machine
NEMA uses 10 wheels, of which four are normal electrical rotors with 26 contacts at each end that are scramble wired in a way unique to each rotor type; one is an electrical reflector (like the Enigma's ''Umkehrwalze'') with one set of 26 pairwise cross connected contacts; and the remaining five are "drive wheels", with mechanical
cams that control the stepping of the rotors and the reflector. The wheels are assembled on an
axle
An axle or axletree is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In the former case, bearing ...
in pairs consisting of a drive wheel and an electrical rotor.
File:NEMA-IMG 0516.jpg, The four rotor pairs and the reflector
File:NEMA-IMG 0520.jpg, The rotor lodging with the cams and first rotor
Image:F-rotor-top-1000.jpg, Top view of a NEMA rotor pair. Electrical rotor "F."
Image:Rotor-bottom-1000.jpg, Bottom view of a NEMA rotor pair. Drive rotor "18." Note the three stepping-control cams.
Image:Enigma-rotor-BP.jpg, An Enigma rotor.
File:NEMA-IMG 0526.jpg, view of the right side of the machine with the port for the removable extra lamp panel
The NEMA machine weighs about 10 kg and measures approximately 36×32×14 cm.
See also
*
Fialka
In cryptography, Fialka (M-125) is the name of a Cold War-era Soviet cipher machine. A rotor machine, the device uses 10 rotors, each with 30 contacts along with mechanical pins to control stepping. It also makes use of a punched card mechanism ...
*
Typex
*
SIGABA
In the history of cryptography, the ECM Mark II was a cipher machine used by the United States for message encryption from World War II until the 1950s. The machine was also known as the SIGABA or Converter M-134 by the Army, or CSP-888/889 by the ...
References
Further reading
* Geoff Sullivan and Frode Weierud: ''The Swiss NEMA Cipher Machine.''
Cryptologia
''Cryptologia'' is a journal in cryptography published six times per year since January 1977. Its remit is all aspects of cryptography, with a special emphasis on historical aspects of the subject. The founding editors were Brian J. Winkel, Davi ...
, 23(4), October 1999, pp310–328.
* Walter Schmid: ''Die Chiffriermaschine Nema.'' 109 pages, third edition, February 2005, Hombrechtikon ZH, Switzerland
External links
Frode Weierud's page on the NEMA– photographs and a simulator
– includes records of NEMA selling prices
– includes scanned manuals
{{DEFAULTSORT:Nema (Machine)
Rotor machines
Cryptographic hardware
Military equipment of Switzerland