Cryptography/Timeline of Notable Events

The desire to keep stored or send information secret dates back into antiquity. As society developed so did the application of cryptography. Below is a timeline of notable events related to cryptography.

  • 3500s - The Sumerians develop cuneiform writing and the Egyptians develop hieroglyphic writing.
  • 1500s - The Phoenicians develop an alphabet
  • 600-500 - Hebrew scholars make use of simple monoalphabetic substitution ciphers (such as the Atbash cipher)
  • c. 400 - Spartan use of scytale (alleged)
  • c. 400BCE - Herodotus reports use of steganography in reports to Greece from Persia (tatoo on shaved head)
  • 100-0 - Notable Roman ciphers such as the Caeser cipher.

1 - 1799 CE

  • ca 1000 - Frequency analysis leading to techniques for breaking monoalphabetic substitution ciphers. It was probably developed among the Arabs, and was likely motivated by textual analysis of the Koran.
  • 1450 - The Chinese develop wooden block movable type printing
  • 1450-1520 - The Voynich manuscript, an example of a possibly encrypted illustrated book, is written.
  • 1466 - Leone Battista Alberti invents polyalphabetic cipher, also the first known mechanical cipher machine
  • 1518 - Johannes Trithemius' book on cryptology
  • 1553 - Belaso invents the (misnamed) Vigenère cipher
  • 1585 - Vigenère's book on ciphers
  • 1641 - Wilkins' Mercury (English book on cryptography)
  • 1586 - Cryptanalysis used by spy master Sir Francis Walsingham to implicate Mary Queen of Scots in the Babington Plot to murder Queen Elizabeth I of England. Queen Mary was eventually executed.
  • 1614 - Scotsman John Napier (1550-1617) published a paper outlining his discovery of the logarithm. Napier also invented an ingenious system of moveable rods (referred to as Napier's Rods or Napier's bones) which were a precursor of the slide rule. These were based on logarithms and allowed the operator to multiply, divide and calculate square and cube roots by moving the rods around and placing them in specially constructed boards.
  • 1793 - Claude Chappe establishes the first long-distance semaphore "telegraph" line
  • 1795 - Thomas Jefferson invents the Jefferson disk cipher, reinvented over 100 years later by Etienne Bazeries and widely used a a tactical cypher by the US Army.


  • 1809-14 George Scovell's work on Napoleonic ciphers during the Peninsular War
  • 1831 - Joseph Henry proposes and builds an electric telegraph
  • 1835 - Samuel Morse develops the Morse code.
  • c. 1854 - Babbage's method for breaking polyalphabetic cyphers (pub 1863 by Kasiski); the first known break of a polyaphabetic cypher. Done for the English during the Crimean War, a general attack on Vigenère's autokey cipher (the 'unbreakable cypher' of its time) as well as the much weaker cypher that is today termed "the Vigenère cypher". The advance was kept secret and was, in essence, reinvented somewhat later by the Prussian Friedrich Kasiski, after whom it is named.
  • 1854 - Wheatstone invents Playfair cipher
  • 1883 - Auguste Kerckhoffs publishes La Cryptographie militare, containing his celebrated "laws" of cryptography
  • 1885 - Beale ciphers published
  • 1894 - The Dreyfus Affair in France involves the use of cryptography, and its misuse, re: false documents.

1900 - 1949

  • c 1915 - William Friedman applies statistics to cryptanalysis ( coincidence counting, etc.)
  • 1917 - Gilbert Vernam develops first practical implementation of a teletype cipher, now known as a stream cipher and, later, with Mauborgne the one-time pad
  • 1917 - Zimmermann telegram intercepted and decrypted, advancing U.S. entry into World War I
  • 1919 - Weimar Germany Foreign Office adopts (a manual) one-time pad for some traffic
  • 1919 - Hebern invents/patents first rotor machine design -- Damm, Scherbius and Koch follow with patents the same year
  • 1921 - Washington Naval Conference - U.S. negotiating team aided by decryption of Japanese diplomatic telegrams
  • c. 1924 - MI8 (Yardley, et al.) provide breaks of assorted traffic in support of US position at Washington Naval Conference
  • c. 1932 - first break of German Army Enigma machine by Rejewski in Poland
  • 1929 - U.S. Secretary of State Henry L. Stimson shuts down State Department cryptanalysis "Black Chamber", saying "Gentlemen do not read each other's mail."
  • 1931 - The American Black Chamber by Herbert O. Yardley is published, revealing much about American cryptography
  • 1940 - break of Japan's Purple machine cipher by SIS team
  • December 7, 1941 - U.S. Naval base at Pearl Harbor surprised by Japanese attack, despite U.S. breaks into several Japanese cyphers. U.S. enters World War II
  • June 1942 - Battle of Midway. Partial break into Dec 41 edition of JN-25 leads to successful ambush of Japanese carriers and to the momentum killing victory.
  • April 1943 - Admiral Yamamoto, architect of Pearl Harbor attack, is assassinated by U.S. forces who know his itinerary from decrypted messages
  • April 1943 - Max Newman, Wynn-Williams, and their team (including Alan Turing) at the secret Government Code and Cypher School ('Station X'), Bletchley Park, Bletchley, England, complete the "Heath Robinson". This is a specialized machine for cypher-breaking, not a general-purpose calculator or computer.
  • December 1943 - The Colossus was built, by Dr Thomas Flowers at The Post Office Research Laboratories in London, to crack the German Lorenz cipher (SZ42). Colossus was used at Bletchley Park during WW II - as a successor to April's 'Robinson's. Although 10 were eventually built, unfortunately they were destroyed immediately after they had finished their work - it was so advanced that there was to be no possibility of its design falling into the wrong hands. The Colossus design was the first electronic digital computer and was somewhat programmable. A epoch in machine capability.
  • 1944 - patent application filed on SIGABA code machine used by U.S. in WW II. Kept secret, finally issued in 2001
  • 1946 - VENONA's first break into Soviet espionage traffic from early 1940s
  • 1948 - Claude Shannon writes a paper that establishes the mathematical basis of information theory
  • 1949 - Shannon's Communication Theory of Secrecy Systems pub in Bell Labs Technical Journal, based on work done during WWII.

1950 - 1999

  • 1951 - U.S. National Security Agency founded, subsuming the US Army and US Navy 'girls school' departments
  • 1968 - John Anthony Walker walks into the Soviet Union's embassy in Washington and sells information on KL-7 cipher machine. The Walker spy ring operates until 1985
  • 1964 - David Kahn's The Codebreakers is published
  • June 8, 1967 - USS Liberty incident in which a U.S. SIGINT ship is attacked by Israel, apparently by mistake, though some continue to dispute this
  • January 23, 1968 - USS Pueblo, another SIGINT ship, is captured by North Korea
  • 1969 - The first hosts of ARPANET, Internet's ancestor, are connected
  • 1974? - Horst Feistel develops the Feistel network block cipher design at IBM
  • 1976 - the Data Encryption Standard was published as an official Federal Information Processing Standard (FIPS) for the US
  • 1976 - Diffie and Hellman publish New Directions in Cryptography article
  • 1977- RSA public key encryption invented at MIT
  • 1981 - Richard Feynman proposes quantum computers. The main application he had in mind was the simulation of quantum systems, but he also mentioned the possibility of solving other problems.
  • 1986 In the wake of an increasing number of break-ins to government and corporate computers, the US Congress passes the Computer Fraud and Abuse Act, which makes it a crime to break into computer systems. The law, however, does not cover juveniles.
  • 1988 - First optical chip developed, it uses light instead of electricity to increase processing speed.
  • 1989 - Tim Berners-Lee and Robert Cailliau built the prototype system which became the World Wide Web at CERN
  • 1991 - Phil Zimmermann releases the public key encryption program PGP along with its source code, which quickly appears on the Internet.
  • 1992 - Release of the movie Sneakers (film)|Sneakers, in which security experts are blackmailed into stealing a universal decoder for encryption systems (no such decoder is known, likely because it is impossible).
  • 1994 - 1st ed of Bruce Schneier's Applied Cryptography is published
  • 1994 - Secure Sockets Layer (SSL) encryption protocol released by Netscape
  • 1994 - Peter Shor devises an algorithm which lets quantum computers determine the factorization of large integers quickly. This is the first interesting problem for which quantum computers promise a significant speed-up, and it therefore generates a lot of interest in quantum computers.
  • 1994 - DNA computing proof of concept on toy traveling salesman problem; a method for input/output still to be determined.
  • 1994 - Russian crackers siphon $10 million from Citibank and transfer the money to bank accounts around the world. Vladimir Levin, the 30-year-old ringleader, uses his work laptop after hours to transfer the funds to accounts in Finland and Israel. Levin stands trial in the United States and is sentenced to three years in prison. Authorities recover all but $400,000 of the stolen money.
  • 1994 - Formerly proprietary trade secret, but not patented, RC4 cipher algorithm is published on the Internet
  • 1994 - first RSA Factoring Challenge from 1977 is decrypted as The Magic Words are Squeamish Ossifrage
  • 1995 - NSA publishes the SHA1 hash algorithm as part of its Digital Signature Standard; SHA0 had a flaw corrected by SHA1
  • 1997 - Ciphersaber, an encryption system based on RC4 that is simple enough to be reconstructed from memory, is published on Usenet
  • 1998 - RIPE project releases final report
  • October 1998 - Digital Millennium Copyright Act (DMCA) becomes law in U.S., criminalizing production and dissemination of technology that can circumvent measures taken to protect copyright
  • October 1999 - DeCSS, a computer program capable of decrypting content on a DVD, is published on the Internet
  • 1999: Bruce Schneier develops the Solitaire cipher, a way to allow field agents to communicate securely without having to rely on electronics or having to carry incriminating tools like a one-time pad. Unlike all previous manual encryption techniques -- except the one-time pad -- this one is resistant to automated cryptanalysis. It is published in Neal Stephenson's Cryptonomicon (2000).

2000 and beyond

  • January 14, 2000 - U.S. Government announce restrictions on export of cryptography are relaxed (although not removed). This allows many US companies to stop the long running, and rather ridiculous process of having to create US and international copies of their software.
  • March 2000 - President Clinton says he doesn't use e-mail to communicate with his daughter, Chelsea Clinton, at college because he doesn't think the medium is secure.
  • September 6, 2000 - RSA Security Inc. released their RSA algorithm into the public domain, a few days in advance of their US patent 4405829 expiring. Following the relaxation of the U.S. government export restrictions, this removed one of the last barriers to the world-wide distribution of much software based on cryptographic systems. It should be noted that the IDEA algorithm is still under patent and also that government restrictions still apply in some places.
  • 2000 - U.K. Regulation of Investigatory Powers Act 2000|Regulation of Investigatory Powers Act requires anyone to supply their cryptographic key to a duly authorized person on request
  • 2001 - Belgian Rijndael algorithm selected as the U.S. Advanced Encryption Standard after a 5 year public search process by National Institute for Standards and Technology (NIST)
  • September 11, 2001 - U.S. response to terrorist attacks hampered by Communication during the September 11, 2001 attacks|lack of secure communications
  • November 2001 - Microsoft and its allies vow to end "full disclosure" of security vulnerabilities by replacing it with "responsible" disclosure guidelines.
  • 2002 - NESSIE project releases final report / selections
  • 2003 - CRYPTREC project releases 2003 report / recommendations
  • 2004 - the hash MD5 is shown to be vulnerable to practical collision attack
  • 2005 - potential for attacks on SHA1 demonstrated
  • 2005 - agents from the U.S. FBI demonstrate their ability to crack WEP using publicly available tools
  • 2007 - NIST announces w:NIST hash function competition
  • 2012 - proclamation of a winner of the w:NIST hash function competition is scheduled
  • 2015 - year by which NIST suggests that 80-bit keys for symmetric key cyphers be phased out. Asymmetric key cyphers require longer keys which have different vulnerability parameters.