Ancient Cryptology Ancient Cryptology Early cryptology emerged between

Ancient Cryptology

Ancient Cryptology -Early cryptology emerged between 3500 and 2000 B. C. with the work of Mesopotamian, Egyptian, Chinese and Indians. -Ancient Egyptians encrypted some of their hieroglyphic writings -The tomb of Khnumhotep II is the oldest known text to deliberately transform its writings to impart dignity and authority - Hebrews used Atbash which is used to designate a letter-forletter replacement process. It is a simple substitution cipher. http: //williamstallings. com/Extras/Security-Notes/lectures/classical. html

Scytale and Polybius Square � The Spartans in 400 B. C. used cryptographic system called scytale. � It is cylinder shaped with leather wrapped around it with a written message • In the 5 th century, Greeks used enciphered warnings about planned surprise attacks � The Greek historian Polybius introduced the Polybius’ checkerboard. � Uses a form of substitution that pairs of numbers substitute letters

Caesar and Alberti’s Involvements �Caesar is well-known in two instances of enciphering: � first documented cipher for military purposes in the Gallic Wars. �Caesar Shift Cipher which replaced each letter with the letter three places further down the alphabet � Battista Alberti invented a cipher wheel. � It was the first polyalphabetic substitution. http: //www. shodor. org/interactivate/activities/Caesar. C ipher/

First Cryptanalysts �The first cryptanalysts were born among the Arabs around the 8 th century �Islam extremists concealed their writings from the orthodox through encipherment � The Subh al-a ‘sha is an Arab encyclopedia detailing all Arabic knowledge of cryptology

Avant-garde � In Europe during the Renaissance, cryptography was becoming a routine diplomatic tool � Cryptanalysis was moving into the West during the 15 th century time � By the 18 th century the telegraph was invented. During the Civil War U. S. Military Telegraph Corps used route ciphers. � Many cryptanalysists invented different ciphers between the 15 th and 18 th century periods: � Giovanni Battista Porta (1535 -1615) invented the earliest digraphic cipher. � Blaise de Vigenere (1523 -1596) invented the first acceptable autokey cipher system. Also the Vigenere Square. � Francis Bacon (1561 -1626) invented the Bilateral cipher. � Thomas Jefferson (1743 -1826) invented the wheel cipher. � Charles Wheatstone invented the digraphic cipher (playfair cipher).

Bibliography �http: //williamstallings. com/Extras/Security- Notes/lectures/classical. html �The code book: the Science of Secrecy from Ancient Egypt to Quantum Cryptography, by Simon Singh, 1999, Anchor Books �http: //www. ieeeghn. org/wiki/index. php/Cryptogra phy �Invitation to Cryptology, By Thomas Barr �http: //www. answers. com/topic/cryptology-history