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

Jana Iyengar <notifications@github.com> Wed, 18 September 2019 02:20 UTC

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Subject: Re: [quicwg/base-drafts] Retransmitting an ACK frame warning (#3049)
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janaiyengar commented on this pull request.



> @@ -3183,7 +3183,8 @@ containing that information is acknowledged.
 
 * 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}}.
+  {{sending-ack-frames}}.  Retransmitting an ACK frame can result in an

This para is not great. That second sentence totally doesn't belong here. Suggested rewrite:

"ACK frames carry the most recent set of acknowledgements and the current Ack Delay estimate. Retransmitting an old ACK frame with stale Ack Delay can cause the peer to generate an inflated RTT sample."

Then in 13.2.1 (sending-ack-frames), add this as the first paragraph:
"ACK frames SHOULD acknowledge both ack-eliciting and non-ack-eliciting packets that have been received but not yet acknowledged."

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