Are fragments of hashes collision-resistent?

Posted by Mark on Stack Overflow See other posts from Stack Overflow or by Mark
Published on 2010-05-01T03:42:24Z Indexed on 2010/05/01 3:47 UTC
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Let me see if someone would mind clearing up this elementary point about md5 and hashing. If you only use the first 4 bytes of an md5 hash, would that mean theoretically only 1 in 255^4 chance of collision. iow is that the intention with it (and other hash algorithms) - that you only have to use a small portion of the returned hash (say the hash is of a file of some size).

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