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

Marsh Ray <marsh@extendedsubset.com> Tue, 11 May 2010 20:05 UTC

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Date: Tue, 11 May 2010 15:04:38 -0500
From: Marsh Ray <marsh@extendedsubset.com>
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To: Nicolas Williams <Nicolas.Williams@oracle.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 5/11/2010 2:46 PM, Nicolas Williams wrote:
> On Tue, May 11, 2010 at 02:32:12PM -0500, Marsh Ray wrote:
>> 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

Isn't one of the implications of the choice of a non-collision-resistant
hash that you must use a completely separate cache for each hostname?

> -- 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.



- Marsh

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