Re: [quicwg/base-drafts] Changing the Default QUIC ACK Policy (#3529)

Gorry Fairhurst <> Mon, 01 June 2020 15:38 UTC

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Date: Mon, 01 Jun 2020 08:38:57 -0700
From: Gorry Fairhurst <>
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Subject: Re: [quicwg/base-drafts] Changing the Default QUIC ACK Policy (#3529)
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Thanks kazuho, 1/8 or 1/4 cwnd seems reasonable, as does using Ack 2 for the first part of slow start ... that closed to what we proposed. And yes there will anyway be cases where any default does not work.

If QUIC decides to retain Ack 2, can we at least capture that Ack 2 with QUIC doesn't have the same return path performance as Ack 2 with TCP - so that people know that less frequent Acts are something to think about from the start?

I'm doing a talk in PANRG this week, and have decided to talk-through this topic (I was already going to talk about things related to return paths). That'll give people a view of some data - and a little thought about the implications this has for QUIC, and whether there is an incentive for network device to thin QUIC to restore performance.

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