Re: [quicwg/base-drafts] Negotiate use of timestamps in ACK frame (#774)

janaiyengar <notifications@github.com> Tue, 19 September 2017 21:34 UTC

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Subject: Re: [quicwg/base-drafts] Negotiate use of timestamps in ACK frame (#774)
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Per-packet timestamps *may* be useful, which is why it makes sense to make them negotiable. Christian lists some use cases above, and we are planning to use it the BBR congestion controller to separate forward path delay variance from reverse-path. This is useful for delay-based congestion controllers in general.

Ian's point about receiving congestion control information "in sequence" instead of all at once has convinced me that having a separate frame would actually hurt, so I'm on board with having it be part of the ACK frame.

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