Re: [quicwg/base-drafts] Ignoring ACK delay can result in wrong RTT calculations (#3350)

Jana Iyengar <> Wed, 15 January 2020 22:26 UTC

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Date: Wed, 15 Jan 2020 14:26:43 -0800
From: Jana Iyengar <>
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Subject: Re: [quicwg/base-drafts] Ignoring ACK delay can result in wrong RTT calculations (#3350)
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Our principle was that an endpoint should not use an RTT sample that is smaller than any RTT it has _directly_ measured.

What is in the draft, as Ian pointed out, is the conservative approach that protects the endpoint from poor reporting of ack delay. A poor min_rtt will lead you astray but that is because the endpoint does not have direct observation of a smaller RTT. Until it does, it is better to be conservative.

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