Subject: [rmcat] Spencer Dawkins' Yes on draft-ietf-rmcat-sbd-11: (with COMMENT)

From: Spencer Dawkins <[email-masked]>
Date: Mon, 02 Apr 2018 07:49:03 -0700

Spencer Dawkins has entered the following ballot position for
draft-ietf-rmcat-sbd-11: Yes

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COMMENT:
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I'm somewhat confused about whether the intended scope for this mechanism is to
detect bottleneck links shared by all flows, or only what's shared by RTP media
flows. The Abstract seems clear about that, but I'm not seeing a similar
statement about scope in the Introduction, unless I'm missing it. Perhaps it's
worth repeating the statement from the Abstract in the Introduction?

I agree with the last sentence in this paragraph,

  The current Internet is unable to explicitly inform endpoints as to
   which flows share bottlenecks, so endpoints need to infer this from
   whatever information is available to them.  The mechanism described
   here currently utilizes packet loss and packet delay, but is not
   restricted to these.  As ECN becomes more prevalent it too will
   become a valuable base signal.

and I'd believe that ECN helps identify path bottlenecks, but I'm not
understanding how ECN helps identify shared bottlenecks, and I think that's the
point being made here.