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

Christian Huitema <notifications@github.com> Mon, 17 December 2018 06:55 UTC

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Subject: Re: [quicwg/base-drafts] kInitialRtt of 100 msec is too aggressive (#2184)
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@martinthomson I don't know what the practical maximum is, I don't have access to telemetry data for that. I would pick 1 second by default, or maybe 1.2 sec for 2 geo-sat hops. I don't particularly worry about having too many packets in flight, I just want to ensure that in the worst case the node has a chance to receive the response to at least the first retransmission before giving up. So I guess if the total wait time is about 1.5 sec we can be fine. Based on what @marten-seemann said, the 100 initial RTT results in a schedule of retransmissions at 200, 600, 1400 and 3000 ms, giving up 6.2 sec after the initial attempt. This seems like plenty. A bit slow, actually.

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