cryptography Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or ''-logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adve ...

, Square (sometimes written SQUARE) is a

block cipher In cryptography, a block cipher is a deterministic algorithm operating on fixed-length groups of bits, called ''blocks''. Block ciphers are specified cryptographic primitive, elementary components in the design of many cryptographic protocols and ...

invented by

Joan Daemen Joan Daemen (; born 1965) is a Belgian cryptographer who co-designed with Vincent Rijmen the Rijndael cipher, which was selected as the Advanced Encryption Standard (AES) in 2001. More recently, he co-designed the Keccak cryptographic hash, wh ...

and

Vincent Rijmen Vincent Rijmen (; born 16 October 1970) is a Belgian cryptographer and one of the two designers of the Rijndael, the Advanced Encryption Standard. Rijmen is also the co-designer of the WHIRLPOOL cryptographic hash function, and the block cip ...

. The design, published in 1997, is a forerunner to Rijndael, which has been adopted as the

Advanced Encryption Standard The Advanced Encryption Standard (AES), also known by its original name Rijndael (), is a specification for the encryption of electronic data established by the U.S. National Institute of Standards and Technology (NIST) in 2001. AES is a variant ...

. Square was introduced together with a new form of cryptanalysis discovered by

Lars Knudsen Lars Ramkilde Knudsen (born 21 February 1962) is a Danish researcher in cryptography, particularly interested in the design and analysis of block ciphers, hash functions and message authentication codes (MACs). Academic After some early work i ...

, called the " Square attack". The structure of Square is a

substitution–permutation network In cryptography, an SP-network, or substitution–permutation network (SPN), is a series of linked mathematical operations used in block cipher algorithms such as AES (Rijndael), 3-Way, Kalyna, Kuznyechik, PRESENT, SAFER, SHARK, and Square. S ...

with eight rounds, operating on 128-bit blocks and using a 128-bit key. Square is not patented.

References

External links

SCAN's entry for Square
Block ciphers {{crypto-stub