Re: [TLS] I-D Action: draft-ietf-tls-ticketrequests-02.txt

Viktor Dukhovni <ietf-dane@dukhovni.org> Thu, 03 October 2019 03:44 UTC

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From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Subject: Re: [TLS] I-D Action: draft-ietf-tls-ticketrequests-02.txt
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> On Oct 2, 2019, at 11:20 PM, Christopher Wood <caw@heapingbits.net> wrote:
> 
> Asking for one upon resumption seems reasonable to me. Thanks to you and Viktor for bringing up this case!

Thanks!  Much appreciated.

My other point, which I probably obscured in too many words, is
that a client that prefers to re-use existing tickets, would
normally want to ask for 0 new tickets, but this should not
necessarily preclude the server from issuing one *as needed*
(STEK rollover, ...).

So there is a difference between a signal that tickets
are simply not wanted, vs. wanted only *as needed*.

Do you have any thoughts on how a client might signal this?

The use-case is clients and servers that don't make use of
early-data, and don't need to avoid traffic analysis.  For
example, MTA-to-MTA traffic, where the client even identifies
in clear text with "EHLO".  Here ticket reuse is the norm,
and renewal is only needed as tickets age.

[ I hope I managed an suitably concise description this time... ]

-- 
-- 
	Viktor.