AES

AES

The AES is the Advanced Encryption Standard. The AES is intended to be issued as a FIPS which is an acronym for the National Institute of Standards and Technology, a division of the U.S. Department of Commerce standard and will replace DES. Most now agree that this venerable cipher is approaching the end of its useful life; DES has not been reaffirmed as a federal standard. In January 1997 the AES initiative was announced and in September 1997 the public was invited to propose suitable block ciphers as candidates for the AES.

Some candidates for the AES

There is considerable interest in the AES initiative and 15 candidates were accepted for consideration in the first round. Among these were close variants of some of the more popular and trusted algorithms currently available, such as RC5, CAST, and SAFER-SK. One of the reasons for close variants being proposed rather than the original ciphers is that one of the criteria for the AES submission is the ability to support 128-bit blocks of plaintext. Most ciphers were developed with an eye to providing a drop-in replacement for DES and, as a result, were often limited to having a 64-bit block size.

Among the fifteen candidates, five candidates have qualified for a second round. Here is a short presentation of the five candidates.They are MARS, RC6, Rijndael, Serpent, Twofish.

The schedule for the AES

It would be surprising if the process for choosing something as important as a block cipher standard for the next 20-30 years (which is the intended lifetime of the AES) were not long and involved. June 15, 1998 was the last day to submit an algorithm. Following that, there was a period of review before five candidates (MARS, RC6, Rijndael, Serpent, Twofish) was chosen for further, more involved scrutiny. From these five, it is intended that the AES will be chosen. It is anticipated that the process will be completed by the year 2001.