Timeline BC ~ 1900 BC: Egyptian writers use non-standard Hieroglyphs in inscriptions of a royal tomb; supposedly this is not the first but the first documented example of written cryptography 1500 an enciphered formula for the production of pottery is done in Mesopotamia parts of the Hebrew writing of Jeremiah's words are written down in "atbash", which is nothing else than a reverse alphabet and one of the first famous methods of enciphering 4th century Aeneas Tacticus invents a form of beacons, by introducing a sort of water-clock 487 the Spartans introduce the so called "skytale" for sending short secret messages to and from the battle field 170 Polybius develops a system to convert letters into numerical characters, an invention called the Polybius Chequerboard. 50-60 Julius Caesar develops an enciphering method, later called the Caesar Cipher, shifting each letter of the alphabet an amount which is fixed before. Like atbash this is a monoalphabetic substitution.

TEXTBLOCK 1/1 // URL: http://world-information.org/wio/infostructure/100437611776/100438659084

RSA The best known of the two-key cryptosystems developed in the mid-1980s is the Rivest-Shamir-Adleman (RSA) cryptoalgorithm, which was first published in April, 1977. Since that time, the algorithm has been employed in the most widely-used Internet electronic communications encryption program, Pretty Good Privacy (PGP). It is also employed in both the Netscape Navigator and Microsoft Explorer web browsing programs in their implementations of the Secure Sockets Layer (SSL), and by Mastercard and VISA in the Secure Electronic Transactions (SET) protocol for credit card transactions.

INDEXCARD, 1/1