Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fast-Track" draft posted

Simon Josefsson <simon@josefsson.org> Tue, 02 February 2010 13:19 UTC

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From: Simon Josefsson <simon@josefsson.org>
To: "Brian Smith" <brian@briansmith.org>
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Date: Tue, 02 Feb 2010 14:19:48 +0100
In-Reply-To: <001901caa3e4$c0363750$40a2a5f0$@org> (Brian Smith's message of "Tue, 2 Feb 2010 02:50:15 -0600")
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Cc: tls@ietf.org
Subject: Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fast-Track" draft posted
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"Brian Smith" <brian@briansmith.org>; writes:

> I am very interested in the ideas that motivate the cached info extension.

Stefan can speak for his reasons, but I see significant advantage in
being able to cache the list of trusted CA certs that is sent from
server to client.  For whatever reasons (which likely include poor
server configuration), I've seen TLS handshakes in the wild that are as
large as 30-40kb which cause some operational pains.

The server certificate _chain_ (note that it is the entire chain that is
cached, not just the server certificate) also has potential of being
large (and growing over time, it seems, as more and more interesting
X.509 extensions are added).

I'm not sure how this relates to the rest of your e-mail though...

/Simon