Last Call Review of draft-ietf-mops-streaming-opcons-10
review-ietf-mops-streaming-opcons-10-opsdir-lc-dunbar-2022-05-06-00

I have reviewed this document as part of the Ops area directorate's ongoing
effort to review all IETF documents being processed by the IESG.  These
comments were written primarily for the benefit of the Ops area directors.
Document editors and WG chairs should treat these comments just like any other
last-call comments.

Summary: the document describes many issues associated with streaming video.
The description is very clear and it is very useful to have those problems
documented.

Some questions for the description of Section 3.2
 The first bullet describes the Media server's adjusting bandwidth in
 responding to the application-level feedback that indicates a bottleneck link
 somewhere along the path.

Question 1: is the "Link" in the sentence referring to the physical link
between two routers along the path? How can application know the all the links
along the path from the server to itself? let alone detecting which link is the
bottleneck?

 The second bullet describes the Media servers adjusting bandwidth by
 implementing some forms of congestion control that probe for bandwidth.
The conclusion says that the QoE is poorer when the two methods don't
coordinate.

Question 2: Both methods are implemented on the Media server, they should
coordinate by nature, aren't they?

Thank you very much,
Linda Dunbar