[TriLUG] MD5 silly question

[Brian Henning]

Hi y'all,
  I'll readily admit that MD5 is quite FM to me yet, but this particular
thing struck me as odd...  I have a php script which uses the php md5(...)
function, and a Java app that uses the MD5 functionality of the
java.security.MessageDigest class.  When I create a hash (of a password
string, in this case) using the php script and compare it to the hash of the
same string created by the Java app, they're not the same.  I always sort of
thought a hash was a hash, and as long as the input was the same, the output
would be the same...  Would someone mind giving me just a brief explanation
(I'm not asking for anything in-depth here) of why two different MD5
programs (for lack of a better word) would generate different hashes for the
same input?  Could it be something like salting?

Thanks!
~Brian

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Brian A. Henning
Strutmasters.com
866.597.2397
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