Re: [quicwg/base-drafts] Retransmitting an ACK frame warning (#3049)

ianswett <> Thu, 24 October 2019 01:34 UTC

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Date: Wed, 23 Oct 2019 18:34:47 -0700
From: ianswett <>
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Subject: Re: [quicwg/base-drafts] Retransmitting an ACK frame warning (#3049)
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ianswett commented on this pull request.

> @@ -3181,9 +3181,10 @@ containing that information is acknowledged.
   unless the endpoint has sent a RESET_STREAM for that stream.  Once an endpoint
   sends a RESET_STREAM frame, no further STREAM frames are needed.
-* The most recent set of acknowledgments are sent in ACK frames.  An ACK frame
-  SHOULD contain all unacknowledged acknowledgments, as described in
-  {{sending-ack-frames}}.
+* ACK frames are sent containing the most recent set of acknowledgements and
+  Ack Delay, as described in {{sending-ack-frames}}. Retransmitting an old ACK
+  frame with stale Ack Delay can cause the peer to generate an inflated RTT
+  sample.

I took part of this, but the first statement is incorrect: ACK frames do not have to contain the highest packet number that has been processed(there was an issue about this).

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