Subject: Re: [avtext] WGLC for draft-ietf-avtext-multiple-clock-rates-08

From: Magnus Westerlund <[email-masked]>
Date: Tue, 2 Apr 2013 11:50:56 +0200

Hi,

I have reviewed the draft and thinks it is in principle ready for
publication. Although it could be possibly be improved by the below
suggested changes:

Section 1:

Slight confusion in the usage of "payload format", "payload type" and
payload

OLD:

   The clock rate is a parameter of the payload format.  It is often
   defined as been the same as the sampling rate but it is not always
   the case (see e.g. the G722 and MPA audio codecs [RFC3551]).

   An RTP sender can switch between different payloads during the
   lifetime of an RTP session and because clock rates are defined by
   payload types, it is possible that the clock rate also varies during
   an RTP session.

NEW:

   The clock rate is a parameter of the payload format as identified in
RTP and RTCP by its payload type value.  It is often
   defined as been the same as the sampling rate but it is not always
   the case (see e.g. the G722 and MPA audio codecs [RFC3551]).

   An RTP sender can switch between different payload formats during the
   lifetime of an RTP session and because clock rates are defined by
   payload format, it is possible that the clock rate also varies during
   an RTP session.

2. Section 4.2:
No reference to Table 4.
OLD:

   Note that in all the formulas, capture_start is the first instant the
   new timestamp rate is used.

NEW:

   Note that in all the formulas, capture_start is the first instant the
   new timestamp rate is used. The output of the above method is
   exemplified in Table 4.

Appendix A.

Each Table should have some indication for what they reference, like

Table 2 - Monotonic Timestamps
Table 3 - Non-monotonic timestamps
Table 4 - Recommended method for RTP Sender (without RTCP)

Cheers

Magnus

On 2013-03-27 22:15, Jonathan Lennox wrote:
> (As WG cochair)
> 
> This is to announce a working group last call for draft-ietf-avtext-multiple-clock-rates-08:
> 
> https://datatracker.ietf.org/doc/draft-ietf-avtext-multiple-clock-rates/
> 
> Please respond to the list by April 17 2013 (i.e. 3 weeks time) with any comments.
> 
> This is intended as a standards track RFC, updating RFC 3550.
> 
> It is helpful to attempt to categorise the type of your comment (including severity) and also to assist to provide any replacement text you feel is necessary.
> 
> If you review the document and have no comments, please tell the chairs that you have reviewed it. This is always useful information in assessing the degree of WG review and consensus behind the document.
> 
> 
> --
> Jonathan Lennox
> [email-masked]
> 
> 
> _______________________________________________
> avtext mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/avtext
> 
> 

-- 

Magnus Westerlund

----------------------------------------------------------------------
Multimedia Technologies, Ericsson Research EAB/TVM
----------------------------------------------------------------------
Ericsson AB                | Phone  +46 10 7148287
Färögatan 6                | Mobile +46 73 0949079
SE-164 80 Stockholm, Sweden| mailto: [email-masked]
----------------------------------------------------------------------

---

From: Colin Perkins <[email-masked]>
Date: Mon, 22 Apr 2013 15:37:40 +0100

> If you review the document and have no comments, please tell the chairs that you have reviewed it. This is always useful information in assessing the degree of WG review and consensus behind the do…

Apologies for the late review. I looked at -09, and think it is ready for publication.

-- 
Colin Perkins
http://csperkins.org/