Message-ID: <4008509B.2060707@techsource.com>
Date: Fri, 16 Jan 2004 15:59:07 -0500
From: Timothy Miller <miller@techsource.com>
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To: Valdis.Kletnieks@vt.edu
CC: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [OT] Redundancy eliminating file systems, breaking MD5, donating
 money to OSDL
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Valdis.Kletnieks@vt.edu wrote:
> On Fri, 16 Jan 2004 15:22:39 EST, Timothy Miller <miller@techsource.com>  said:
> 
> 
>>Think about it!  If we had a filesystem that actually DID this, and it 
>>was in the Linux kernel, it would spread far and wide.  It's bound to 
>>happen that someone will identify a collision.  We then report that to 
>>the committee offering the reward and then donate it to OSDL to help 
>>Linux development.
> 
> 
> Actually, it's *not* "bound to happen".  Figure out the number of blocks you'd
> need to have even a 1% chance of a birthday collision in a 2**128 space.
> 
> And you'd need that many disk blocks on *a single system*.
> 
> Then figure out the chances of a collision on a small machine that only has 20
> or 30 terabytes (yes, in this case terabytes is small).

Certainly.  No one machine is going to find it in a reasonable period. 
OTOH, if a million machines were doing it, it increases the chances by 
just that much.

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