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Re: [quicwg/base-drafts] kInitialRtt of 100 msec is too aggressive (#2184)

ianswett <notifications@github.com> Mon, 17 December 2018 16:22 UTC

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Subject: Re: [quicwg/base-drafts] kInitialRtt of 100 msec is too aggressive (#2184)
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Chrome currently uses a 4 second timeout on the client if it hasn't received anything back.  That's fairly long , but 1 second is certainly to short based on what I know.  That being said, RTTs >1s are only really common on 2g, so one could use a much shorter timeout if you knew more about the network.

@mikkelfj As Marten pointed out, the current retransmission schedule is 200, 600, 1400 and 3000 ms, etc, so US/Europe connections only incur a spurious retransmit if the RTT is >200ms or there's loss.

So like Jana, I think 100ms is reasonable, but I think we should add some more text about predicting RTT based on past network measurements, even if they're not on resumed connections.

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