Re: How to shorten output of a hash function?

Kristian Gjøsteen <kristiag+news@xxxxxxxxxxxx> writes:
Phil Carmody <thefatphil_demunged@xxxxxxxxxxx> wrote:
If it doesn't appear to be a PRF it's not a hash, IMHO.

That opinion is wrong. Sorry.

(Ok, I'll explain: VSH is clearly a hash function. Chaum-van
Heijst-Pfitzmann as well. Neither look very much like random
functions.)

I've got to admit that, on princple, I don't like the idea of
anything which has a <<O(2^(n/2)) work factor to find collisions
for an n-bit hash to be worthy of the title 'n-bit hash'.

Very Sub-exponential Hash, I think you'll find...

Phil
--
The fact that a believer is happier than a sceptic is no more to the
point than the fact that a drunken man is happier than a sober one.
The happiness of credulity is a cheap and dangerous quality.
-- George Bernard Shaw (1856-1950), Preface to Androcles and the Lion
.

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