Twofish
Sign in to saveIn cryptography, Twofish is a symmetric key block cipher with a block size of 128 bits and key sizes up to 256 bits. It was one of the five finalists of the Advanced Encryption Standard contest, but it was not selected for standardization. Twofish is related to the earlier block cipher Blowfish.
Key facts
- Block cipher.name
- Twofish
- Block cipher.image
- 320px|center
- Block cipher.caption
- The Twofish algorithm
- Block cipher.designers
- Bruce Schneier
- Block cipher.publish date
- 1998
- Block cipher.derived from
- Blowfish, SAFER, Square
- Block cipher.related to
- Threefish
- Block cipher.certification
- AES finalist
- Block cipher.key size
- 128, 192 or 256 bits
- Block cipher.block size
- 128 bits
- Block cipher.structure
- Feistel network
- Block cipher.rounds
- 16
- Block cipher.cryptanalysis
- Truncated differential cryptanalysis requiring roughly 251 chosen plaintexts. Impossible differential attack that breaks 6 rounds out of 16 of the 256-bit key version using 2256 steps.
via Wikipedia infobox
Article
6 sectionsContents
- Performance
- Cryptanalysis
- See also
- References
- Articles
- External links
In cryptography, Twofish is a symmetric key block cipher with a block size of 128 bits and key sizes up to 256 bits. It was one of the five finalists of the Advanced Encryption Standard contest, but it was not selected for standardization. Twofish is related to the earlier block cipher Blowfish.
Twofish's distinctive features are the use of pre-computed key-dependent S-boxes, and a relatively complex key schedule. One half of an n-bit key is used as the actual encryption key and the other half of the n-bit key is used to modify the encryption algorithm (key-dependent S-boxes). Twofish borrows some elements from other designs; for example, the pseudo-Hadamard transform (PHT) from the SAFER family of ciphers. Twofish has a Feistel structure like DES. Twofish also employs a Maximum Distance Separable matrix.