Also a block cipher algorithm designed by Dr. Joan Daemen, Dr. Lars Knudsen, and Dr. Vincent Rijmen, that formed the basis for the design of the NIST AES algorithm Rijndael. The algorithm is so named because the transformations involved consider each 128-bit block the cipher operates on as a 4 byte by 4 byte square. This same construction is also used in Rijndael. It has a block and key size of both 128 bits, and was designed from the outset to be resistant to both differential cryptanalysis and linear cryptanalysis, however a dedicated chosen plaintext attack specific to the cipher's construction was found that breaks it if 6 or less rounds are performed. It is recommended to use the cipher with at least 8 rounds.