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Re: [TLS] Collisions (Re: Nico's suggestions - Re: Consensus Call:

Nicolas Williams <Nicolas.Williams@oracle.com> Tue, 11 May 2010 19:49 UTC

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Date: Tue, 11 May 2010 14:46:21 -0500
From: Nicolas Williams <Nicolas.Williams@oracle.com>
To: Marsh Ray <marsh@extendedsubset.com>
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Cc: "Kemp, David P." <DPKemp@missi.ncsc.mil>, tls@ietf.org
Subject: Re: [TLS] Collisions (Re: Nico's suggestions - Re: Consensus Call:
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On Tue, May 11, 2010 at 02:32:12PM -0500, Marsh Ray wrote:
> On 5/11/2010 2:09 PM, Nicolas Williams wrote:
> > 
> > Fatal errors are fatal.  But the error here isn't quite as fatal.  I
> > suppose I can agree to view as such though and then there's no real
> > problem.
> 
> 1. Caching can't be done on the first handshake (for obvious reasons)
> 
> 2. Cached info must be thrown out on any failure to successfully
> complete a handshake (for security reasons)
> 
> So how much better is this caching scheme than what you could have today
> with session resumption?

I recall this question being asked long ago.  IIRC the idea is that you
could cache a cert chain for many servers' certs -- if they all have the
same validation chain, then you don't need to get a copy of it every
time you connect to one.  Also, session resumption state does expired,
whether kept as state on the server or via tickets.

Nico
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