I have reviewed draft-ietf-codec-oggopus-10 as part of the Operational directorate's ongoing effort to review all IETF documents being processed by the IESG.  These comments were written with the intent of improving the operational aspects of the IETF drafts. Comments that are not addressed in last call may be included in AD reviews during the IESG review.  Document editors and WG chairs should treat these comments just like any other last call comments. This memo defines an encapsulation for the Opus interactive speech and audio codec. Documents of this type, how to encapsulate some information for transport over other protocols, rarely have direct operational impacts, and this ID is not an exception.  I found the document to be clearly written (modulo some of the sections on output gain and downmixing, which are likely clearer to someone working in the field than they are to me) So I judge the document to be ready for publication. That said, I wonder if it would be possible to as a OAM-like ability to support "in-band" condition information - for example by adding an OAM channel to the channel mapping function (i.e. the "Opus Channel Mapping Families" registry) where the definition would be that the channel is for the use of OAM services and is otherwise passed unmodified.    Having the ability to have real time "what the customer is seeing" RTCP like, but with more expansion abilities, feedback could be quite helpful operations-wise Scott