> discussion, although it appears to me that you're already made up your
> mind.  

I'd prefer to say I have little interest in a technology which, by
design, will retrieve a completely different chunk of data than what was
written, with no notice whatsoever.  BTW, before you bring out tape
errors again, I posted long ago why this argument was not comparable.

No point in beating the poor Birthday Paradox to death; you've
completely missed the point there.  It doesn't matter that the same
values come up more often than our intuition suggests--which is the
_only_ lesson of BP--what matters is if you use a shorthand to track the
values which can't tell that Feb 7 and Dec 28 are different values
because you put them in the same hash bucket and therefore think that
everything that bucket is Feb 7, you retrieve the wrong data.

Here's all a thinking person responsible for data needs to consider:

An 8KB chunk of data can have 2^65536 possible values.  Representing
that 8KB of data in 160 bits means that each of the 2^160 possible
checksum/hash/fingerprint values MUST represent, on average, 2^65376
*different* 8KB chunks of data.  

If that doesn't concern you, well, it's safe to say I won't be hiring
you as my backup admin.  Or as my technology consultant, since you
should know from earlier postings that spoofing your favorite 160-bit
hashing algorithm with reasonable-looking fake data is now old hat.  The
exploit itself should concern us, not to mention that it also
illustrates that similar data which yields the same hash is not the
once-in-the-lifetime-of-the-universe oddity you portray.

Everything mentioned here was covered in the original postings a month
ago.  Unless there's something new, I'm done with this.


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