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Document: draft-ietf-tsvwg-fecframe-ext-04
Reviewer: Christer Holmberg
Review Date: 2018-09-14
IETF LC End Date: 2018-09-24
IESG Telechat date: Not scheduled for a telechat

Summary: The document is well written, but there is an issue regarding backward compatibility that I want the authors to address.

Major issues:

Q1_MAJ:

Regarding backward compatibility, it's difficult for me to parse the second bullet in Section 1.

The text seems to assume that SDP, and RFC 6364, are used to negotiate FEC. But, RFC 6364 is only an informative reference, and I assume FEC does not even mandate SDP?

Is there a generic requirement that the endpoints must negotiate the usage of this mechanism before it is used? Or, can the mechanism be used towards an endpoint that does not support it?

Minor issues:

N/A

Nits/editorial comments: 

Q2_ED.

The document uses "extends RFC 6363" terminology in a couple of places. I suggest to use "updates" instead.

Q3_ED.

Section 1 says:

     'This document is fully backward compatible with [RFC6363] that it extends but does not replace."

I don't think you need the "extends but does not replace" part.