In cryptography, N-hash is a cryptographic hash function based on the FEAL round function, and is now considered insecure. It was proposed in 1990 in an article by Miyaguchi, Ohta, and Iwata; weaknesses were published the following year.
N-hash has a 128-bit hash size. A message is divided into 128-bit blocks, and each block is combined with the hash value computed so far using the g compression function. g contains eight rounds, each of which uses an F function, similar to the one used by FEAL.
Eli Biham and Adi Shamir (1991) applied the technique of differential cryptanalysis to N-hash, and showed that collisions could be generated faster than by a birthday attack for N-hash variants with even up to 12 rounds.
- S. Miyaguchi, K. Ohta, and M. Iwata (November 1990). "128-bit hash function (N-hash)". NTT Review. 2 (6): 128–132.CS1 maint: uses authors parameter (link)
- Eli Biham, Adi Shamir (1991). "Differential Cryptanalysis of Feal and N-Hash". EUROCRYPT. Lecture Notes in Computer Science. 547: 1–16. doi:10.1007/3-540-46416-6_1. ISBN 978-3-540-54620-7.CS1 maint: uses authors parameter (link)