In cryptography

Cryptography

Cryptography is the practice and study of techniques for secure communication in the presence of third parties...

, decorrelation theory is a system developed by Serge Vaudenay

Serge Vaudenay

Serge Vaudenay is a well-known French cryptographer.Serge Vaudenay entered the École Normale Supérieure in Paris as a normalien student in 1989. In 1992, he passed the agrégation in mathematics. He did his PhD at the computer science laboratory of École Normale Supérieure, and defended it in 1995...

 for designing block cipher

Block cipher

In cryptography, a block cipher is a symmetric key cipher operating on fixed-length groups of bits, called blocks, with an unvarying transformation. A block cipher encryption algorithm might take a 128-bit block of plaintext as input, and output a corresponding 128-bit block of ciphertext...

s to be provably secure

Provable security

In cryptography, a system has provable security if its security requirements can be stated formally in an adversarial model, as opposed to heuristically, with clear assumptions that the adversary has access to the system as well as enough computational resources...

 against differential cryptanalysis

Differential cryptanalysis

Differential cryptanalysis is a general form of cryptanalysis applicable primarily to block ciphers, but also to stream ciphers and cryptographic hash functions. In the broadest sense, it is the study of how differences in an input can affect the resultant difference at the output...

, linear cryptanalysis

Linear cryptanalysis

In cryptography, linear cryptanalysis is a general form of cryptanalysis based on finding affine approximations to the action of a cipher. Attacks have been developed for block ciphers and stream ciphers...

, and even undiscovered cryptanalytic attacks meeting certain broad criteria. Ciphers designed using these principles include COCONUT98

COCONUT98

In cryptography, COCONUT98 is a block cipher designed by Serge Vaudenay in 1998...

 and the AES candidate

Advanced Encryption Standard process

The Advanced Encryption Standard , the block cipher ratified as a standard by National Institute of Standards and Technology of the United States , was chosen using a process markedly more open and transparent than its predecessor, the aging Data Encryption Standard...

 DFC

DFC (cipher)

In cryptography, DFC is a block cipher which wascreated in 1998 by a group of researchers from École Normale Supérieure, CNRS, and France Télécom and submitted to the AES competition.Like other AES candidates, DFC operates on blocks of 128 bits, using a key of 128, 192, or 256 bits...

, both of which have been shown to be vulnerable to some forms of cryptanalysis not covered by the theory.

External links

• Introduction to Decorrelation Theory Online manual by Serge Vaudenay