|Designers||Kaisa Nyberg and Lars Knudsen|
|Key sizes||198 bits|
|Block sizes||64 bits|
|Best public cryptanalysis|
|Jakobsen & Knudsen's higher order differential cryptanalysis breaks KN-Cipher with only 512 chosen plaintexts and 241 running time, or with 32 chosen plaintexts and 270 running time.|
In cryptography, KN-Cipher is a block cipher created by Kaisa Nyberg and Lars Knudsen in 1995. One of the first ciphers designed to be provably secure against ordinary differential cryptanalysis, KN-Cipher was later broken using higher order differential cryptanalysis.
Presented as "a prototype...compatible with DES", the algorithm has a 64-bit block size and a 6-round Feistel network structure. The round function is based on the cube operation in the finite field GF(233).
- T. Jakobsen, L.R. Knudsen (January 1997). The Interpolation Attack on Block Ciphers (PDF/PostScript). 4th International Workshop on Fast Software Encryption (FSE '97). Haifa: Springer-Verlag. pp. 28–40. Retrieved 23 January 2007.
- K. Nyberg, L.R. Knudsen (1995). "Provable Security Against a Differential Attack" (PDF/PostScript). Journal of Cryptology. 8 (1): 27–37. doi:10.1007/bf00204800. ISSN 0933-2790. Retrieved 23 January 2007.