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Re: [TLS] TLS ECH, how much can the hint stick out?

"Salz, Rich" <rsalz@akamai.com> Mon, 14 September 2020 17:50 UTC

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From: "Salz, Rich" <rsalz@akamai.com>
To: Karthik Bhargavan <karthikeyan.bhargavan@inria.fr>, Ben Schwartz <bemasc@google.com>
CC: "tls@ietf.org" <tls@ietf.org>
Thread-Topic: [TLS] TLS ECH, how much can the hint stick out?
Thread-Index: AQHWhfO3LY/7Fxe3IU+rRAfSRwB2r6ljvr2AgAAChwCAAcISAIAC78CA
Date: Mon, 14 Sep 2020 17:50:13 +0000
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Subject: Re: [TLS] TLS ECH, how much can the hint stick out?
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  *   So, hiding whether a server supports ECH or not (which I called level 2) is a significantly higher bar than hiding whether a particular connection is using ECH or not (level 1).

  *   I would like to understand how the WG feels about this requirement and that there is consensus that we need (2) and not just (1).

I do not see Level 2 being a requirement.  (I don’t see how you could make it work but I’m not a cryptographer.)

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