Difference between revisions of "MD4 hash"

From AMule Project FAQ
Jump to: navigation, search
(reword)
Line 1: Line 1:
−
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>
+
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.  
−
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.
+
  
−
[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].
+
[[aMule]] uses MD4 hashes to ensure that no transmission errors corrupt in the files you share. Its MD4 algorithm is based on [[libcrypto|Crypto++]].
  
−
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.
+
MD4 was developed by MIT professor Ronald L. Rivest. It was accepted by the RSA in October 1990.
  
−
[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.
+
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==
−
[[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++]]).
+
* [http://www.faqs.org/rfcs/rfc1186.html RFC 1186: MD4]
−
 
+
* [http://www.faqs.org/rfcs/rfc1319.html RFC 1319: MD2]
−
NOTE : the hash used in ed2k protocol URLs in NOT MD4 !!!
+
* [http://www.faqs.org/rfcs/rfc1320.html RFC 1320: MD4]
−
It is similar but not the same. Above certain filesize (the exact value is documented somewhere) the MD4 and the ed2k hash for the same data are not the same. Anybody can check this by computing a hash of any file greater than 15 megabytes using any hash tool, like HashCalc, fsum etc.
+
* [http://theory.lcs.mit.edu/~rivest Home page of Ronald L. Rivest]
 +
* [http://www.rsa.com RSA]

Revision as of 21:28, 28 December 2006

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++.

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

Retrieved from "http://wiki.amule.org/t/index.php?title=MD4_hash&oldid=9696"