Subject: [TLS] Mirja Kühlewind's No Objection on draft-ietf-tls-sni-encryption-05: (with COMMENT)

From: Mirja Kühlewind via Datatracker <[email-masked]>
Date: Mon, 09 Sep 2019 09:07:06 -0700

Mirja Kühlewind has entered the following ballot position for
draft-ietf-tls-sni-encryption-05: No Objection

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COMMENT:
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Thanks for clearly writing down attacks and requirements in this document.

One small technical comment on this sentence:
Sec 2.3: "Per-stream
   QoS can be provided by a combination of packet marking and end-to-end
   agreements."
If this sentence is meant to mean use of DSCP, I don't think this is true, as
DSCP is usually not available end-to-end but most often gets changed or
bleached somewhere on the path.

And two editorial comments:

Sec 2.1: "The SNI was defined to facilitate management of servers, though the
   developers of middleboxes soon found out that they could take
   advantage of the information."
"soon found out" does sound a bit story-telling like to me. I recommend a more
objective phrasing like: "The SNI was defined to facilitate management of
servers, though other usages by middleboxes also take
   advantage of the information."
or something similar...

Also sec 2.1: "The SNI is probably also included in the general collection of
   metadata by pervasive surveillance actors."
This sentence is phrased a bit speculatively and at the same kind seems
inherently true as a "pervasive surveillance actor" usually just collect all
available data/traffic... I guess the more interesting question would be if and
how this information is used. Anyway I recommend some rephrasing like: "The SNI
could also be utilised by the general collection of
   metadata by pervasive surveillance actors."