Advanced Encryption StandardThe Advanced Encryption Standard is the result of a 3 year long public request for proposals that was started in 1997 by the NIST (National Institute Of Standards and Technology) a unit of the U.S. Commerce Department. In 1999 five finalists where chosen from over 15 submissions, namely Rijndael, Mars, RC6, Serpent and Twofish. All algorithms had to fullfill several preconditions: At the end of the standardization process, Rijndael, a cipher developed by the two Belgian cryptoanalysts Joan Daemen and Vincent Rijmen was announced the winner and became the successor of the Data Encryption Standard. Rijndael uses a variable number of rounds, depending on key/block sizes, as follows: 9 rounds if the key/block size is 128 bits 11 rounds if the key/block size is 192 bits 13 rounds if the key/block size is 256 bits Rijndael is a substitution linear transformation cipher, not requiring a Feistel network. It uses triple discrete invertible uniform transformations (layers). The technical description of the new standard was published by the NIST as FIPS PUB 197 in the year 2001.
Links: AESLounge at Graz University of Technology (find out about recent attacks on AES and different AES implementations) www.iaik.tugraz.ac.at/research/krypto/AES/ A good description of the Rijndael scheme www.eng.tau.ac.il/~yash/cryptonetsec/rijndael.htm Find out how AES works by using this applet Biography of Vincent Rijmen www.nist.gov/public_affairs/releases/biovince.htm Biography of Joan Daemen www.nist.gov/public_affairs/releases/biojoan.htm

