Re: [TLS] Justification

Michael D'Errico <mike-list@pobox.com> Wed, 12 May 2010 17:51 UTC

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Date: Wed, 12 May 2010 10:26:39 -0700
From: Michael D'Errico <mike-list@pobox.com>
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To: Adam Langley <agl@google.com>
References: <20100510221531.GC9429@oracle.com> <4BE9B0BC.2000101@extendedsubset.com> <20100511194620.GU9429@oracle.com> <4BE9B856.40000@extendedsubset.com> <20100511200728.GW9429@oracle.com> <4BE9CC88.6040103@extendedsubset.com> <87aas5sbzy.fsf@mocca.josefsson.org> <4BEAC145.60607@pobox.com> <n2va84d7bc61005120811o737c2011i27f9d40e88417539@mail.gmail.com> <004901caf1ea$783e23a0$68ba6ae0$@briansmith.org> <p2xa84d7bc61005120858v2ce68cf7xe6ddf559faf4d4b0@mail.gmail.com>
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Cc: tls@ietf.org
Subject: Re: [TLS] Justification
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Adam Langley wrote:
 > This is very close to the three packet limit.

What is this three packet limit you speak of?

Mike




Adam Langley wrote:
> On Wed, May 12, 2010 at 11:47 AM, Brian Smith <brian@briansmith.org> wrote:
>> I don't think that a caching mechanism based on hashing the OCSP responses is going to be optimal for this. A different caching mechanism that allows the client to ask specifically for only *newer* (not just *different*) OCSP responses would be much better.
> 
> The specific case that I'm worried about is a client connecting to a
> server for which the previously cached OCSP responses have expired.
> 
> As an example, consider a server which returns two certificates: 806
> and 807 bytes long. The OCSP responses for these certs are 1085 bytes
> long. So the total return is 3783 bytes, not including the overhead of
> the ServerHello etc. This is very close to the three packet limit.
> 
> 
> AGL