[rtcweb] WGLC review of draft-ietf-rtcweb-rtp-usage-13

Ben Campbell <ben@nostrum.com> Fri, 09 May 2014 21:56 UTC

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Date: Fri, 9 May 2014 16:56:12 -0500
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Subject: [rtcweb] WGLC review of draft-ietf-rtcweb-rtp-usage-13
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This draft seems well constructed. I don't have much in the way of technical comments, but do have a few extremely minor/editorial comments:




-- 4.1, 2nd to last bullet:

Can there be a reference for " RTCP timer reconsideration "

-- 4.3, last paragraph: "RTP receivers MUST follow the recommendations in Section 4.3 of [RFC7160] in order to support ..."

I assume that you mean that receivers MUST support the recommendations because they need to support multiple clock rates. A strained interpretation could assume that, if they want to support multiple clock rates, they MUST support..."

-- 4.5, first paragraph: " ... support for multiplexing RTP data packets and RTCP control packets on a single transport-layer flow for each RTP session is REQUIRED, provided it is negotiated in the signalling channel ..."

I assume the intent is that support...is REQUIRED, but only _used_ if negotiated? As written, it seems to say _support_ is both REQUIRED and negotiated. 

(A similar construction occurs in 4.6, 2nd paragraph)

-- 5.2.2, last paragraph:

If I understand 6904 correctly, you signal the use of encryption for each header you want to encrypt, right? If so, then how is "explicitly disabled through ... signalling" different than "not signalled"? If it's the same thing, then this comes perilously close saying "... RECOMMENDED that the encryption be used ... unless you don't want to." 

 (I have no objection to the "explicitly disabled through the API" )

-- Figures 1 and 2:

Any chance of centering these?

-- 12.1.3:

How does (or will) DART fit in here? Seems like it might have something to say, but I'm not sure how the timing relates.