Re: Is MD5 outdated ?

From: David Taylor (davidt-news_at_yadt.co.uk)
Date: 10/06/03 

Date: Sun, 5 Oct 2003 23:17:26 +0000 (UTC)

Mxsmanic <mxsmanic@hotmail.com> wrote on Mon, 06 Oct 2003 00:42:54 +0200:
[..snip..]
>
> I'm surprised that you argue with it, though, since it is logically
> inevitable. When the hash is a random function of the message, any
> change in the hash--including a single-bit change--will typically
> correspond to a change of about 50% of the bits in the message. And
> conversely, any change in the message--including a single-bit
> change--will typically correspond to a change of about 50% of the bits
> in the hash.

Your statement contradicts itself. If a single-bit change of the message
results in a change typically changes 50% of the bits in the hash, how can
"any change in the hash" (say 50% of the bits changing) typically
correspond to a change of about 50% of the bits in the message? 

-- 
David Taylor
davidt-news@yadt.co.uk
"The future just ain't what it used to be."

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