Re: [tcpm] Thank you for the QUIC session in tcpm

Yuchung Cheng <> Fri, 09 November 2018 00:38 UTC

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From: Yuchung Cheng <>
Date: Thu, 8 Nov 2018 16:37:55 -0800
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To: Bob Briscoe <>
Cc: Jana Iyengar <>, Ian Swett <>, tcpm IETF list <>
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Subject: Re: [tcpm] Thank you for the QUIC session in tcpm
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On Thu, Nov 8, 2018 at 3:14 AM, Bob Briscoe <> wrote:
> I just wanted to thank Jana for explaining QUIC loss recovery to us (and QUIC CC as far as it goes).
> And thank you Jana, Ian, the chairs of both WGs (and anyone else involved) for setting it up.
> If one is not full-time on QUIC, it's very difficult to keep up with all the changes. But now we have a checkpoint to start from, I feel I will not be wasting people's time if I try to get involved - at least I only might say something un-QUIC occasionally, rather than nearly always. This has allowed people who understand how TCP cold be improved to help with QUIC, when working on QUIC isn't their day job.
> Again, Thank you.
I like particularly that QUIC only reduces cwnd to 1 after the loss is
confirmed not upon RTO fires. It should be very feasible for TCP (at
least Linux) w/ TCP timestamps. It'll save a lot of spurious cwnd

Also IMHO TCP w/ quality timestamps are almost as good as QUIC
pkt-ids. Google internally uses usec. We wish we could upstream it but
RFC needs to be updated.

> Bob
> --
> ________________________________________________________________
> Bob Briscoe                     
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