In cryptography

Cryptography

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

, higher-order differential cryptanalysis is a generalization of 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...

, an attack against 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. Developed in 1994 by Lars Knudsen

Lars Knudsen

Lars Ramkilde Knudsen is a Danish researcher in cryptography, particularly interested in the design and analysis of block ciphers, hash functions and message authentication codes .-Academic:...

, the technique has been applied to a number of ciphers. Whereas ordinary differential cryptanalysis analyzes the differences between two texts, the higher-order variant considers differences between differences, etc. It has been shown to be more powerful than a first-order attack in some cases (see KN-Cipher).