# MD4

MD4 (English Message-Digest Algorithm 4) is a published 1990 by Ronald L. Rivest cryptographic hash function. It was developed with the aim to run on 32 -bit machines very quickly and easy to be implemented simultaneously. Of course, should the basic requirements remain on hash functions. MD4 produces a hash value with a length of 128 bits.

However, it soon became apparent that the process is uncertain. Is particularly problematic the lack of crashworthiness turned out. In Crypto Bytes Journal of the RSA, a method was published, which could produce identical messages within an hour to two to a sign that gave the same hash value. Rivest himself confirmed the uncertainty in RFC 1321: The MD5 Message-Digest Algorithm, so that even RSA advises against the use of this message digest. MD4 was licensed as public domain, whereupon due probably is that the principle used has become the basis of further hash functions.

## MD4 hashes

The 128 -bit MD4 hashes (English and "message - digests " ) will normally be listed as a 32- digit hexadecimal number. The following example shows a 59 -byte ASCII input and the corresponding MD4 hash:

Md4 ( " quick brown fox completely dilapidated taxi across Bavaria ") = 3270fd28f1b28cd219bb946bd372fc00 A small change in the message generates almost certainly a completely different hash. With Frank instead Franz gives:

Md4 ( " Frank chases in the completely dilapidated taxi across Bavaria ") = c95704f5b2928c67a0970a576cebc589 The hash of a zero-length string is:

MD4 ("") = 31d6cfe0d16ae931b73c59d7e0c089c0 Example of a collision:

839c7a4d7a92cb5678a5d5b9eea5a7573c8a74deb366c3dc20a083b69f5d2a3bb3719dc69891e9f95e809fd7e8b23ba6318edd45e51fe39708bf9427e9c3e8b9 839c7a4d7a92cbd678a5d529eea5a7573c8a74deb366c3dc20a083b69f5d2a3bb3719dc69891e9f95e809fd7e8b23ba6318edc45e51fe39708bf9427e9c3e8b9 ^ ^ ^ These strings differ on the marked with '^' bodies. Two hex digits define one byte of the 64 -byte MD4 input. They both deliver the hash value:

4d7e6a1defa93d2dde05b45d864c429b see also

- Message-Digest Algorithm 2
- Message-Digest Algorithm 5