Re: [quicwg/base-drafts] ACK generation recommendation (#3304)

Jana Iyengar <> Thu, 19 December 2019 03:48 UTC

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Date: Wed, 18 Dec 2019 19:48:07 -0800
From: Jana Iyengar <>
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Subject: Re: [quicwg/base-drafts] ACK generation recommendation (#3304)
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> Shouldn't that largely depend on server implementation?

Yes, specifically the congestion controller. My question was directed at @ianswett, about experiments with Chrome's strategy for a server that does Cubic. My point is that the client here (Chrome) has decided to use an ACKing strategy that works well with BBR (that's what Google servers use), but as Ian notes, that strategy may cause perf regressions for a server that speaks Cubic or Reno. Since most QUIC servers out there are unlikely to be speaking BBR (this is simply my assertion), my question was about the extent of this degradation.

I understand why this is not simple, and that is why I've opened this issue -- we have a recommendation right now in the draft that suggests that we know a good answer.

I will send out a PR shortly, which should help make this conversation more concrete.

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