[vox-tech] shell script challenge - Now MD5sum erratia

Micah Cowan vox-tech@lists.lugod.org
Thu, 8 Aug 2002 11:53:37 -0700


GNU Linux writes:
 > Found a very interesting page on md5sum. It's:
 > 
 > http://hills.ccsf.org/~jharri01/project.html
 > 
 > "So why does MD5 seem so secure? Because 128 bits allows you to have
 > 2128=340,282,366,920,938,463,463,374,607,431,768,211,456 different
 > possible MD5 codes"
 > 
 > Lots of good reading for insomniacs.

It still shouldn't be relied upon, however, that two identical MD5
checksums are sufficient evidence that the corresponding files are
identical; I've heard more than one person claim to have encountered
identical MD5 sums for different files, and its certainly not
impossible, just improbable.

But it's a heluva lot better than running diff from one file to every
other file - a factorial-time operation! :)

-Micah