Re: [quicwg/base-drafts] Retransmitting ACK frames can inflate RTT (#3048)

ianswett <> Wed, 18 September 2019 01:49 UTC

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Subject: Re: [quicwg/base-drafts] Retransmitting ACK frames can inflate RTT (#3048)
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ianswett commented on this pull request.

> @@ -291,6 +291,13 @@ are received within an RTT.  As suggested in {{?RFC6298}}, doing so might result
 in inadequate history in smoothed_rtt and rttvar.  Ensuring that RTT estimates
 retain sufficient history is an open research question.
+### Retransmitted ACK frames
+Section 13.3 of {{QUIC-TRANSPORT}} recommends sending the most recent set of
+acknowledgements in ACK frames, but if ACK frames are retransmitted, an inflated

I originally wrote that, but it's likely to be inflated anyway, particularly if max_ack_delay is < RTT.

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