Re: [quicwg/base-drafts] ECN "not quite enough" (#4022)

Gorry Fairhurst <> Thu, 20 August 2020 07:59 UTC

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Date: Thu, 20 Aug 2020 00:59:18 -0700
From: Gorry Fairhurst <>
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Subject: Re: [quicwg/base-drafts] ECN "not quite enough" (#4022)
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No. I think this is not the same understanding of what it means to say "verify support for ECN". What I see as validation, is the act of setting a CE code point and seeing this echoed by the remote endpoint. To me this can be done at the sending endpoint and the resulting ECN feedback can safely ignored from a CC perspective when it refers to the packet was intentionally CE-marked.

(This does not confirm the devices on path observe or remark, simply that if a known CE-mark is inserted by the sender, this is in fact observed by the receiver and generates a response to the sender. I agree that knowledge whether the path updates ECT-marks is not a part of the spec.)

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