Subject: [straw] Mirja Kühlewind's No Objection on draft-ietf-straw-b2bua-rtcp-15: (with COMMENT)

From: "Mirja Kuehlewind" <[email-masked]>
Date: Tue, 22 Nov 2016 10:56:35 -0800

Mirja Kühlewind has entered the following ballot position for
draft-ietf-straw-b2bua-rtcp-15: No Objection

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COMMENT:
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High level comment:
This document mainly talks about cases where the SSRC or the RTP seq# is
changed. Are they no other fields that could be changed as well? Would
there need to be additional guidance (in 3.2) then, or are SSRC and seq#
more special then other fields? And why would a relay change those
fields? Wouldn't it be appropriate to give the guidance somewhere that
those fields SHOULD NOT be changed!?!

Smaller comments:

section 3.1:
"Apart from the
   mentioned attributes, B2BUAs SHOULD forward all other SDP attributes
   they don't have a reason not to forward, in order to avoid breaking
   additional functionality endpoints may be relying on."
Shouldn't that be a MUST (with all the exceptions given already)...?

"...a B2BUA MAY rewrite CNAME items if any potential collision
   is detected..."
And why is that a MAY? Shouldn't this be a SHOULD at least?