Paul Bernstein (cryptologist)

Paul Alfred Bernstein (born December 14, 1891 in Debschwitz ; † August 1, 1976 in Esslingen am Neckar ) was a German engineer and cryptologist who contributed to the design of the Enigma rotor key machine during the first half of the 20th century of the Second World War to encrypt the communications of the German Wehrmacht .

Life

The “trading machine” invented by Arthur Scherbius (1923) did not yet have rings

Little is known about Bernstein's life. He was born as the son of Albin Bernstein and his wife Berta, geb. von Dulz, born and was of Protestant religion . On July 20, 1918, he married Wally Anna Maria Rummelandt (* 1894) in Berlin. There he was a development engineer at Chiffriermaschinen AG (ChiMaAG) in Berlin in the 1920s . The company was founded on July 9, 1923 in order to manufacture and further develop the Enigma rotor cipher machine invented by Arthur Scherbius (1878–1929) in 1918 .

Shortly after Scherbius' basic patent application "Encryption apparatus" (No. 416219) of February 23, 1918 and the subsequent "Encryption apparatus" (No. 425147) of September 26, 1920, Paul Bernstein filed several patent applications, which were granted in early 1924 in quick succession. Contrary to what has been widely published, however, he did not invent the "locking ring" (the later ring positions ), but this was done solely by his colleague Willi Korn , as can be seen from patent US1905593, in which only his name is given as the inventor.

Paul Bernstein, however, invented the "irregular rotor increment". In the patent granted on March 26, 1924, the inventor is named: "Paul Bernstein in Charlottenburg ".

According to his description of the invention (Patent No. 429122) there were four cipher rollers and an additional four toothed drive wheels with gaps, which ensured that the cipher rollers were indexed irregularly, with the following configuration:

11 positions with 5 teeth and 6 gaps
15 positions with 9 teeth and 6 gaps
17 positions with 11 teeth and 6 gaps
19 positions with 11 teeth and 8 gaps

The transmission realized in this way with four gears and the relatively prime positions resulted in a period of 11 · 15 · 17 · 19 = 53,295. Compared with the period of the trading machine of 26 ⁴ or 456,976 possible positions of the four cipher rollers, the German cryptologist - Professor Friedrich Bauer described it as “almost a progressive cipher”. This was a cryptographic strength of the trading machine that later models (from Enigma-A ) were missing.

Paul Bernstein left ChiMaAG in 1925. The Berlin notary's registry records under no. 203 of July 4, 1925 that his power of attorney has expired, and notes: "The same [Paul Bernstein] has left the company." survived the war and died at the age of 84 in Esslingen am Neckar.

Patents

Cipher machine. German patent DE411126, August 18, 1923, PDF
Electric key cipher. German patent DE407804, January 18, 1924, PDF
Electric encryption and decryption machine. German patent DE425566, February 28, 1924, PDF
Cipher machine with a plurality of cipher rollers which cause the characters to be interchanged. German patent DE429122, March 26, 1924, PDF
Electric Cipher Writing Machine. U.S. Patent US1777425, October 7, 1930, PDF

literature

Friedrich L. Bauer : Deciphered Secrets. Methods and maxims of cryptology. 3rd, revised and expanded edition. Springer, Berlin a. a. 2000, ISBN 3-540-67931-6 .
David Kahn : The Code Breakers - The Story of Secret Writing . Macmillan USA, Reissue 1974, ISBN 0-02-560460-0 .
Anders Wik: The First Classical Enigmas - Swedish Views on Enigma Development 1924–1930. Proceedings of the 1st Conference on Historical Cryptology (HistoCrypt), Uppsala 2018, pp. 83-88, PDF , accessed February 18, 2019.

Web links

Crypto Museum Paul Bernstein and the " Writing Enigma " (English)

Individual evidence

↑ Marriage certificate No. 444/1918, Berlin registry office, July 20, 1918.
↑ Certificate No. 546/1976, registry office Esslingen am Neckar
↑ Marriage certificate No. 444/1918, Berlin registry office, July 20, 1918.
↑ Louis Kruh, Cipher Deavours: The commercial Enigma - Beginnings of machine cryptography . Cryptologia, Rose-Hulman Institute of Technology, Taylor & Francis, Philadelphia PA 26.2002,1 (January), p. 2. ISSN 0161-1194 , accessed February 18, 2019. PDF; 0.8 MB
↑ Friedrich L. Bauer: Deciphered secrets. Methods and maxims of cryptology. 3rd, revised and expanded edition. Springer, Berlin a. a. 2000, p. 117.
^ Colleen Carper: Bletchley's Secret War - British Code Breaking in the Batlle of the Atlantic. Ashbrook Statesmanship Thesis, 2009, p. 3, PDF
↑ Louis Kruh, Cipher Deavours: The Commercial Enigma - Beginnings of Machine Cryptography . Cryptologia, Vol.XXVI, No. 1, January 2002, p. 11. apprendre-en-ligne.net (PDF; 0.8 MB), accessed on February 18, 2019.
↑ US1905593 Coding Machine. 5 claims Application date November 12, 1929 and in Germany November 16, 1928 (PDF; 487 kB). Granted April 25, 1933. Applicant: Willi Korn of Berlin-Friedenau, Germany, accessed June 5, 2019.
↑ Friedrich L. Bauer: Deciphered secrets. Methods and maxims of cryptology. 3rd, revised and expanded edition. Springer, Berlin a. a. 2000, p. 140.
↑ Cipher machine with a plurality of cipher rollers which interchange the characters. German patent DE429122, March 26, 1924, PDF , accessed on February 18, 2019.
↑ Friedrich L. Bauer: Deciphered secrets. Methods and maxims of cryptology. 3rd, revised and expanded edition. Springer, Berlin a. a. 2000, p. 140.

personal data
SURNAME	Bernstein, Paul
ALTERNATIVE NAMES	Bernstein, Paul Alfred (full name)
BRIEF DESCRIPTION	German cryptologist
DATE OF BIRTH	December 14, 1891
PLACE OF BIRTH	Debschwitz
DATE OF DEATH	1976
Place of death	Esslingen am Neckar

[1] Marriage certificate No. 444/1918, Berlin registry office, July 20, 1918.

[2] Certificate No. 546/1976, registry office Esslingen am Neckar

[3] Marriage certificate No. 444/1918, Berlin registry office, July 20, 1918.

[4] Louis Kruh, Cipher Deavours: The commercial Enigma - Beginnings of machine cryptography . Cryptologia, Rose-Hulman Institute of Technology, Taylor & Francis, Philadelphia PA 26.2002,1 (January), p. 2. ISSN 0161-1194 , accessed February 18, 2019. PDF; 0.8 MB

[5] Friedrich L. Bauer: Deciphered secrets. Methods and maxims of cryptology. 3rd, revised and expanded edition. Springer, Berlin a. a. 2000, p. 117.

[6] Colleen Carper: Bletchley's Secret War - British Code Breaking in the Batlle of the Atlantic. Ashbrook Statesmanship Thesis, 2009, p. 3, PDF

[7] Louis Kruh, Cipher Deavours: The Commercial Enigma - Beginnings of Machine Cryptography . Cryptologia, Vol.XXVI, No. 1, January 2002, p. 11. apprendre-en-ligne.net (PDF; 0.8 MB), accessed on February 18, 2019.

[8] US1905593 Coding Machine. 5 claims Application date November 12, 1929 and in Germany November 16, 1928 (PDF; 487 kB). Granted April 25, 1933. Applicant: Willi Korn of Berlin-Friedenau, Germany, accessed June 5, 2019.

[9] Friedrich L. Bauer: Deciphered secrets. Methods and maxims of cryptology. 3rd, revised and expanded edition. Springer, Berlin a. a. 2000, p. 140.

[10] Cipher machine with a plurality of cipher rollers which interchange the characters. German patent DE429122, March 26, 1924, PDF , accessed on February 18, 2019.

[11] Friedrich L. Bauer: Deciphered secrets. Methods and maxims of cryptology. 3rd, revised and expanded edition. Springer, Berlin a. a. 2000, p. 140.