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

This document discusses the types of congestion control feedback using the RTP Control Protocol. The document analyzes the feedback packet sizes and content for point-to-point Voice Telephony and point-to-point Conference call. 

Since most of today's conference bridges are multi-points to multi-points or at least multi-points (users) to multi-servers, I think multi-points analysis would be more useful. Will the author consider adding them? 

As for the Consideration of the RTCP feedback (Section 2), should you also consider how far away the endpoints are?  Will network congestion and distances impact the RTCP feedback? 

Section 1 states, "It is also assumed that the congestion control feedback mechanism in RFC8888, .. are available." Question: Is the Congestion Control Feedback mechanism described in this document the same as in RRC 8888? What are the key differences? 

The Security Considerations Section content is good. 

Cheers, 
Linda Dunbar