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Re: [quicwg/base-drafts] Update initial congestion window on MTU decrease (#3998)

Martin Thomson <notifications@github.com> Fri, 14 August 2020 01:50 UTC

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Date: Thu, 13 Aug 2020 18:50:07 -0700
From: Martin Thomson <notifications@github.com>
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Subject: Re: [quicwg/base-drafts] Update initial congestion window on MTU decrease (#3998)
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@martinthomson commented on this pull request.



> +If the maximum datagram size is decreased in order to complete the handshake,
+the initial congestion window SHOULD be recalculated with the new smaller size.
+This avoids overly large initial congestion windows.  The initial window is
+not recalculated at any other time.

So if we are forced to reset to the initial window after going idle, we can't reset the congestion controller and calculate an initial using the current path MTU?  It seems to me like you might reasonably assume that an MTU is viable for longer than a congestion window.

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