Re: [quicwg/base-drafts] Explain asymmetric confirmation condition (#2881)

Marten Seemann <> Tue, 09 July 2019 08:31 UTC

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From: Marten Seemann <>
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Subject: Re: [quicwg/base-drafts] Explain asymmetric confirmation condition (#2881)
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Depending on the application this is actually quite likely, or even the common case. Assume that the client has a bit of data to send in the first flight, then this would fill up the cwnd completely. You don't even need must, just 10 packets, minus the Handshake packets in flight (which might contain a certificate chain), and their retransmissions.

> Why? The retransmitted Handshake packets aren't and in this case these are the ones that will run the CWND down. The 1-RTT PING barely counts.

The problem is not the size of the 1-RTT PING, but the fact that we might already be congestion limited once we try to send it.

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