[quicwg/base-drafts] Remove Requirement of an Acknowledgement per Round Trip (#3030)

Nick Banks <notifications@github.com> Fri, 13 September 2019 16:31 UTC

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Date: Fri, 13 Sep 2019 09:31:07 -0700
From: Nick Banks <notifications@github.com>
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Subject: [quicwg/base-drafts] Remove Requirement of an Acknowledgement per Round Trip (#3030)
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The spec gives no reason (that I can see) as to why an ACK frame must be sent at least once per round trip (assuming there are ack-eliciting packets to acknowledge), effectively overwriting the ACK delay logic when the RTT is very small. If the RTT is smaller than the platform's timer granularity, this isn't really even possible.

I propose to remove this requirement. If the WG instead feels that we should keep this requirement, then there should be a reasoning for it; and probably an update to the PTO calculation as well.

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