Difference between revisions of "MD4 hash"

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An [http://www.faqs.org/rfcs/rfc1320.html MD4] hash is a unique value given as a result of a mathematical expression following the [http://www.faqs.org/rfcs/rfc1320.html MD4 algorithm] which claims to ensure data integrity.<br>
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<center>'''English''' | [[MD4_hash-de|Deutsch]]</center>
It provides a 128-bit (16 [[byte]]s, 32 hex chars) message digest from the data input (the input may be of any length) that is claimed to be unique.
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[http://www.faqs.org/rfcs/rfc1320.html MD4] was developed by [http://theory.lcs.mit.edu/~rivest Professor Ronald L. Rivest] of [http://web.mit.edu MIT] and accepted by the [http://www.rsa.com RSA] on [http://www.faqs.org/rfcs/rfc1186.html October 1990] and then redesigned on [http://www.faqs.org/rfcs/rfc1320.html April 1992].
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An '''MD4 hash''' is a unique value produced by a mathematical calculation. It provides a 128-bit (16 [[byte]]s, 32 hex chars) key from the data input which is claimed to be unique. As such, MD4 hashes are used to ensure data integrity.  
  
Both [http://www.faqs.org/rfcs/rfc1320.html MD4] and its successor [http://userpages.umbc.edu/~mabzug1/cs/md5/md5.html MD5] (which is an extension of [http://www.faqs.org/rfcs/rfc1320.html MD4]) are optimized for 32-bit machines, while its predecessor [http://www.faqs.org/rfcs/rfc1319.html MD2] was optimized for 8-bit machines.
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[[aMule]] uses MD4 hashes to ensure that no transmission errors corrupt in the files you share. Its MD4 algorithm is based on [[libcrypto|Crypto++]].
  
[http://www.faqs.org/rfcs/rfc1320.html MD4] is known to be fast, but possibly not absolutely secure. On the other hand, [http://userpages.umbc.edu/~mabzug1/cs/md5/md5.html MD5] is not as fast as the [http://www.faqs.org/rfcs/rfc1320.html MD4] algorithm, but offers much more assurance of data security.
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Important note! although ed2k hash is based on MD4, it is '''not''' MD4. the algorithm for computing ed2k hash is as follows:
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# split the file into blocks of 9728000 bytes
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# compute MD4 hash digest of each file block separately
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# concatenate the list of block digests into one big byte array
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# compute MD4 of array created in step #3. this is the ed2k hash.
  
[[aMule]] incorporates the [http://www.faqs.org/rfcs/rfc1320.html MD4] algorithm based on the [[libcrypto|Crypto++]]'s library sources (in some beta [[aMule]] v2 releases, it did actually use [[libcrypto|Crypto++]]).
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MD4 was developed by MIT professor Ronald L. Rivest. It was accepted by the RSA in October 1990.
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Both MD4, and its successor MD5, are optimized for 32-bit machines. Its predecessor MD2 was optimized for 8-bit machines. MD4 is known to be fast, but possibly not absolutely secure. On the other hand, MD5  is not as fast as MD4 but offers much more assurance of data security.
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==External links==
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* [http://www.faqs.org/rfcs/rfc1186.html RFC 1186: MD4]
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* [http://www.faqs.org/rfcs/rfc1319.html RFC 1319: MD2]
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* [http://www.faqs.org/rfcs/rfc1320.html RFC 1320: MD4]  
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* [http://theory.lcs.mit.edu/~rivest Home page of Ronald L. Rivest]
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* [http://www.rsa.com RSA]

Latest revision as of 16:13, 3 September 2007

English | Deutsch

An MD4 hash is a unique value produced by a mathematical calculation. It provides a 128-bit (16 bytes, 32 hex chars) key from the data input which is claimed to be unique. As such, MD4 hashes are used to ensure data integrity.

aMule uses MD4 hashes to ensure that no transmission errors corrupt in the files you share. Its MD4 algorithm is based on Crypto++.

Important note! although ed2k hash is based on MD4, it is not MD4. the algorithm for computing ed2k hash is as follows:

  1. split the file into blocks of 9728000 bytes
  2. compute MD4 hash digest of each file block separately
  3. concatenate the list of block digests into one big byte array
  4. compute MD4 of array created in step #3. this is the ed2k hash.

MD4 was developed by MIT professor Ronald L. Rivest. It was accepted by the RSA in October 1990.

Both MD4, and its successor MD5, are optimized for 32-bit machines. Its predecessor MD2 was optimized for 8-bit machines. MD4 is known to be fast, but possibly not absolutely secure. On the other hand, MD5 is not as fast as MD4 but offers much more assurance of data security.

External links