The History of Cryptography

  • 1900 BCE

    Non-Standard use of hieroglyphs

    An Egyptian scribe used non-standard hieroglyphs in an inscription. This has been considered to be the first documented example of written cryptography.
  • 1500 BCE

    Enciphered formula for pottery glazes

    A Mesopotamian tablet is used that contains an enciphered formula for the making of glazes for pottery.
  • 50 BCE

    Caesar's Cipher

    Caesar's Cipher
    Julius Caesar used a simple substitution cipher with the normal alphabet, by shifting the letters by a few letter places, in government communication. We now call this method the Caesar cipher.
  • Jan 1, 1226

    Political cryptography appears in Venice Archives

    A political cryptography appeared in the archives of Venice, wherein dots or crosses replaced the vowels in a few scattered words.
  • Jan 1, 1379

    Gabrieli di Lavinde creates a cipher

    Gabrieli di Lavinde at the request of Clement VII, compiled a combination substitution alphabet and small code. It is believed this is the first example of the nomenclator. This particular code/cipher was to remain in general use among diplomats and some civilians for the next 450 years. Although there were stronger ciphers being invented in the meantime, it is believed this use can be attributed to its relative convenience.
  • Jan 1, 1466

    Leon Battista Alberti invents polyalphabetic cipher

    Leon Battista Alberti invents polyalphabetic cipher
    Leon Battista Alberti invented and published the first polyalphabetic cipher, designing a cipher disk, now commonly referred to as the Captain Midnight Decoder Badge, to simplify the process. This type of cipher was apparently not broken until the 1800's. Alberti also wrote extensively on the state of the art in ciphers, besides his own invention.
  • Jan 1, 1518

    Johannes Trithemius publishes "Polygraphia"

    Johannes Trithemius publishes "Polygraphia"
    Johannes Trithemius wrote the first printed book on cryptology. He invented a steganographic cipher wherein each letter was represented as a word taken from a succession of columns. He also described polyalphabetic ciphers in the now standard form of rectangular substitution tables. He introduced the notion of changing alphabets with each letter.
  • Sir Francis Bacon introduces a bilateral cipher

    Sir Francis Bacon introduces a bilateral cipher
    Sir Francis Bacon described a cipher, which now bears his name. He created a bilateral cipher which is known today as a 5-bit binary encoding. He advanced it as a steganographic device by using variation in type face to carry each bit of the encoding.
  • Thomas Jefferson invents his wheel cipher

    Thomas Jefferson invents his wheel cipher
    Thomas Jefferson, invented his wheel cipher. This was re-invented in several forms later and used in WW-II by the US Navy as the Strip Cipher. Jefferson's wheel cipher consisted of thirty-six cylindrical wooden pieces, each threaded onto an iron spindle. The letters of the alphabet were inscribed on the edge of each wheel in a random order. By turning these wheels, words could be scrambled and unscrambled.
  • Gilbert S. Vernam invented a cipher machine

    Gilbert S. Vernam, whle working for AT&T, invented a practical polyalphabetic cipher machine capable of using a key which is totally random and never repeats. This is the only provably secure cipher, as far as we know. The machine was offered to the Government for use in WW-I but it was rejected. It was put on the commercial market in 1920.
  • Japanese Purple machine was invented

    Japanese Purple machine was invented
    The Japanese Purple machine was invented in response to revelations by Herbert O. Yardley and broken by a team headed by William Frederick Friedman. The Purple machine used telephone stepping relays instead of rotors. The US Army SIS was able to break the cipher used for the six letters before it was able to break the one used for the 20 others.
  • The Lucifer cipher

    The Lucifer cipher
    Dr. Horst Feistel led a research project at the IBM Watson Research Lab in the 1960's which developed the Lucifer cipher. This later inspired the US DES and other product ciphers, creating a family labeled ``Feistel ciphers''. The Lucifer cipher is one of the earliest civilian used block ciphers.
  • DES comes to life

    A design by IBM, based on the Lucifer cipher was born in 1976. With changes (including both S-box improvements and reduction of key size) by the US NSA, it was chosen to be the U.S. Data Encryption Standard(now known as DES). It has since found worldwide acceptance, largely because it has shown itself strong against 20+ years of attacks. Even some who believe it is past its useful life use it as a component still.
  • Diffie and Hellman published ``New Directions in Cryptography''

    Whitfield Diffie and Martin Hellman published ``New Directions in Cryptography'', introducing the idea of public key cryptography. They also put forth the idea of authentication by powers of a one way function, now used in the S/Key challenge/response utility.
  • International Data Encryption Algorithm is born

    International Data Encryption Algorithm is born
    Xuejia Lai and James Massey, in Switzerland ,published ``A Proposal for a New Block Encryption Standard'', a proposed International Data Encryption Algorithm (IDEA), designed to replace DES. IDEA uses a 128-bit key and employs operations which are convenient for general purpose computers, therefore making software implementations more efficient.
  • Pretty Good Privacy is created

    Pretty Good Privacy is created
    Phil Zimmermann released his first version of PGP (Pretty Good Privacy) in response to the threat by the FBI to demand access to the cleartext of the communications of citizens. PGP offered high security to the general public. PGP is especially notable because it was released as freeware and has become a worldwide standard, while its competitors of the time remain generally unknown.
  • US Government relaxes restrictions on exportation of cryptography

    U.S. Government announce restrictions on export of cryptography are relaxed, although they were not removed entirely. This allowed many US companies to stop the long running process of having to create both US and international copies of their software.
  • RSA algorithm released to public domain

    RSA Security Inc. released their RSA algorithm into the public domain, a few days in advance of their U.S. Patent 4,405,829 expiring. Following the relaxation of the U.S. government export restrictions, this removed one of the last barriers to the worldwide distribution of a great deal of software based on cryptographic systems
  • Users attack with keys to the AACS system

    Users swamped with copies of a 128-bit key to the AACS system used to protect HD DVD and Blu-ray video discs. The user revolt was a response to Digg's decision, later reversed, to remove the keys. This was done, largely, due to demands from the motion picture industry that cited the U.S. DMCA anti-circumvention provisions.
  • Playstation 3's security is attacked

    Playstation 3's security is attacked
    The master key for High-bandwidth Digital Content Protection (HDCP) and the private signing key for the Sony PlayStation 3 game console are recovered and published using separate cryptoanalytic attacks. The fail0verflow group of hackers, revealed the initial exploit at the Chaos Communication Congress in Berlin, in December 2010.