Twofish (cipher): Difference between revisions
imported>Sandy Harris No edit summary |
imported>Sandy Harris No edit summary |
||
| Line 10: | Line 10: | ||
is a [[block cipher]] from [[Bruce Schneier]]'s company [[Counterpane]]. It was designed as a candidate cipher for the [[AES competition]], and was a finalist though not the winner. Like all candidates, it uses 128-bit blocks and supports key sizes of 128, 192 or 256 bits. It is a 16-round [[#Feistel structure | Feistel cipher]] using four key-dependent 8*8 S-boxes. | is a [[block cipher]] from [[Bruce Schneier]]'s company [[Counterpane]]. It was designed as a candidate cipher for the [[AES competition]], and was a finalist though not the winner. Like all candidates, it uses 128-bit blocks and supports key sizes of 128, 192 or 256 bits. It is a 16-round [[#Feistel structure | Feistel cipher]] using four key-dependent 8*8 S-boxes. | ||
Except for the name, and using key-dependent S-boxes, it has little relationship to [[Blowfish (cipher)| Blowfish]]; Twofish was a new design. It uses [[ | Except for the name, and using key-dependent S-boxes, it has little relationship to [[Blowfish (cipher)| Blowfish]]; Twofish was a new design. It uses [[pseudo-Hadamard transform]]s in the round function. It has a successor named "Threefish", used in the [[Skein (hash algorithm) | Skein]] hash algorithm, a candidate in the [[Advanced Hash Standard]] contest. That is another new design. | ||
The cipher is freely available for any use. It has a home page; see [[Block_cipher/External_Links#Homepages_for_block_ciphers | external links]]. | The cipher is freely available for any use. It has a home page; see [[Block_cipher/External_Links#Homepages_for_block_ciphers | external links]]. | ||
Revision as of 23:12, 24 November 2009
Twofish [1] is a block cipher from Bruce Schneier's company Counterpane. It was designed as a candidate cipher for the AES competition, and was a finalist though not the winner. Like all candidates, it uses 128-bit blocks and supports key sizes of 128, 192 or 256 bits. It is a 16-round Feistel cipher using four key-dependent 8*8 S-boxes.
Except for the name, and using key-dependent S-boxes, it has little relationship to Blowfish; Twofish was a new design. It uses pseudo-Hadamard transforms in the round function. It has a successor named "Threefish", used in the Skein hash algorithm, a candidate in the Advanced Hash Standard contest. That is another new design.
The cipher is freely available for any use. It has a home page; see external links.
References
- ↑ Bruce Schneier, John Kelsey, Doug Whiting, David Wagner, Chris Hall, Niels Ferguson (1998), Twofish: A 128-Bit Block Cipher