Re: [quicwg/base-drafts] Pacing when under-utilizing the Congestion Window (#2686)

Gorry Fairhurst <> Wed, 22 May 2019 14:52 UTC

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Date: Wed, 22 May 2019 14:52:54 +0000
From: Gorry Fairhurst <>
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Subject: Re: [quicwg/base-drafts] Pacing when under-utilizing the Congestion Window (#2686)
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I'm not advocating a max burst size of 4 (although I do believe this is safe, other sizes larger may also be safe), however my thought was that the draft infers IW as a safe size to burst - I don't know that this is always true - especially if we look to the future use of a larger IW. You could (I think you do) argue that IW is an upper bound to this safe burst size without pacing.

I will try just a little more: 
• I think we **should** limit the cwnd when coming out of an app-limited period. 
• I think we should limit a burst <= some size or that pacing is needed, or if not then it MUST (!) reduce to a safe IW.

Does that help?

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