Speck (cipher)
3 rounds of Speck with 2-word key schedule | |
| General | |
|---|---|
| Designers | Ray Beaulieu, Douglas Shors, Jason Smith, Stefan Treatman-Clark, Bryan Weeks, Louis Wingers NSA |
| First published | 2013 |
| Related to | Simon, Threefish |
| Cipher detail | |
| Key sizes | 64, 72, 96, 128, 144, 192 or 256 bits |
| Block sizes | 32, 48, 64, 96 or 128 bits |
| Structure | ARX |
| Rounds | 22–34 (depending on block and key size) |
| Speed | 2.6 cpb (5.7 without SSE) on Intel Xeon 5640 (Speck128/128) |
| Best public cryptanalysis | |
| No attacks are known on the full ciphers, but reduced-round versions have been attacked. Differential cryptanalysis can break about 70–75% of the rounds of most variants slightly faster than brute-force; see #Cryptanalysis. | |
Speck is a family of lightweight block ciphers publicly released by the National Security Agency (NSA) in June 2013. Speck has been optimized for performance in software implementations, while its sister algorithm, Simon, has been optimized for hardware implementations. Speck is an add–rotate–xor (ARX) cipher.
The NSA began working on the Simon and Speck ciphers in 2011. The agency anticipated some agencies in the US federal government would need a cipher that would operate well on a diverse collection of Internet of Things devices while maintaining an acceptable level of security.