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Re: [hybi] Computation part of handshake

Dave Cridland <dave@cridland.net> Fri, 25 February 2011 21:49 UTC

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Date: Fri, 25 Feb 2011 21:50:25 +0000
From: Dave Cridland <dave@cridland.net>
To: Silvio Ventres <silvio.ventres@gmail.com>, "Salvatore.Loreto@ericsson.com" <Salvatore.Loreto@ericsson.com>, Server-Initiated HTTP <hybi@ietf.org>, "jhildebr@cisco.com" <jhildebr@cisco.com>, Willy Tarreau <w@1wt.eu>
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Subject: Re: [hybi] Computation part of handshake
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On Fri Feb 25 17:34:54 2011, Silvio Ventres wrote:
> The question is, why use hashing at all ?
> Use some simple math, why add complexity ?

Just thought I'd pick up on this.

It's just a very common method of taking an input and producing an  
output that is both verifiable and very unlikely to clash (ie,  
collide) with an output for a different input, even if the inputs are  
similar.

It's *really* hard to find "simple math" that gets even close to  
this, and hashes are very widely implemented even on hardware, and as  
such a useful building block. In addition, one hash operation is  
pretty cheap, these days.

Dave.
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