Tim Cook <z99### [at] gmailcom> wrote:
> Invisible wrote:
> > Now, here's a thought. MD5 produces a 128-bit hash value. So what are 
> > the changes of two random datums having the same hash?
> > 
> > 2^128 = 3.40 * 10^38

> And yet, it's not possible to just keep a record of MD5 hashes and 
> backward-compute the file that generated it (or even a reasonably small 
> list and a note as to which one should be used) (and save an awful lot 
> of storage space).

  Well, rather obviously. An MD5 has can be used to store at most 64 bytes
of data (meaning that all possible combinations of 64 bytes can be stored
there, but no more).

-- 
                                                          - Warp

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