International Data Encryption Algorithm

Abstract: In this paper, we describe the Advanced Encryption Standard (AES), which has been approved after an international competition by the National Institute of Standards and Technology.

Abstract: We propose a new block cipher as a candidate for the Advanced Encryption Standard. Its design is highly conservative, yet still allows a very efficient implementation. It uses S-boxes similar to those of DES in a new structure that simultaneously allows a more rapid avalanche, a more efficient bitslice implementation, and an easy analysis that enables us to demonstrate its security against all known types of attack. With a 128-bit block size and a 256-bit key, it is as fast as DES on the market leading Intel Pentium/MMX platforms (and at least as fast on many others); yet we believe it to be more secure than three-key triple-DES.

Abstract: Double encryption has been suggested to strengthen the Federal Data Encryption Standard (DES). A recent proposal suggests that using two 56-bit keys but enciphering 3 times (encrypt with a first key, decrypt with a second key, then encrypt with the first key again) increases security over simple double encryption. This paper shows that although either technique significantly improves security over single encryption, the new technique does not significantly increase security over simple double encryption. Cryptanalysis of the 112-bit key requires about 256 operations and words of memory, using a chosen plaintext attack. While DES is used as an example, the technique is applicable to any similar cipher.

Abstract: In October 2000, the National Institute of Standards and Technology (NIST) announced that the Rijndael algorithm had been selected to be the new Advanced Encryption Standard (AES). NIST's announcement concluded a three and a half year search process in which fifteen candidate algorithms from twelve countries were evaluated on the basis of security, computational efficiency, algorithm simplicity, and flexibility. The AES will become a Federal Information Processing Standard (FIPS), thereby replacing the aging and obsolete Data Encryption Standard (DES) as the cryptographic algorithm employed by US Government agencies and the private sector to encrypt sensitive information.