Re: [quicwg/base-drafts] Eliminating the fixed minimum RTO (#1017)

Subodh Iyengar <notifications@github.com> Fri, 15 December 2017 20:27 UTC

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Date: Fri, 15 Dec 2017 20:27:07 +0000
From: Subodh Iyengar <notifications@github.com>
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Subject: Re: [quicwg/base-drafts] Eliminating the fixed minimum RTO (#1017)
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Strongly agree with this proposal. 

I think communicating MAD is very important to replace this. There could be a case that a sender decided to set their RTO too low due to a receiver delaying ACKs. I anticipate that this might happen right after the handshake because handshake packets would be acked usually immediately thus setting RTO close to the RTT, however after handshake the receiver might start delaying acks for regular data. 

Another case is if a spurious RTO triggers an ACK from the receiver QUIC would only get an RTT sample from the ack of the RTO instead of getting the sample from the original packet. So it seems important to include ack delay into the RTO computations.

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