Re: [quicwg/base-drafts] Define under-utilizing the congestion window (#2675)

Jana Iyengar <> Fri, 17 May 2019 01:42 UTC

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From: Jana Iyengar <>
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Subject: Re: [quicwg/base-drafts] Define under-utilizing the congestion window (#2675)
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janaiyengar commented on this pull request.

> @@ -848,9 +850,10 @@ and not fully utilize the congestion window due to this delay. A sender
 should not consider itself application limited if it would have fully
 utilized the congestion window without pacing delay.
-Bursting more than an intial window's worth of data into the network might
-cause short-term congestion and losses. Implemementations SHOULD either use
-pacing or reduce their congestion window to limit such bursts.
+Sending multiple packets into the network without any delay between them
+creates a burst of load that might cause short-term congestion and losses.

>  The existing text says you SHOULD not burst more than an initial window into the network(ever), with nothing specific to coming out of quiescence.

Yes, I think this is the problem. I believe the intent here was to say that a sender SHOULD NOT do more than IW as an upper limit on bursts without recommending that as the correct limit for any bursting.

We can either specify that _all_ bursts should be limited to IW, irrespective of how much data is in the network already, or that bursts coming out of quiescence should be limited to IW. While I'm not sure how to change this text here, I'm trying to steer clear of saying something overly broad. (I'll suggest some text).

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