Subject: [AVT] [Technical Errata Reported] RFC5404 (1669)

From: RFC Errata System <[email-masked]>
Date: Mon, 26 Jan 2009 10:42:16 -0800 (PST)

The following errata report has been submitted for RFC5404,
"RTP Payload Format for G.719".

--------------------------------------
You may review the report below and at:
http://www.rfc-editor.org/errata_search.php?rfc=5404&eid=1669

--------------------------------------
Type: Technical
Reported by: Alfred Hoenes <[email-masked]>

Section: 7.1, pg.18

Original Text
-------------
   CBR:  Constant Bitrate (CBR) indicates the exact codec bitrate in
      bits per second (not including the overhead from packetization,
      RTP header, or lower layers) that the codec MUST use.  "CBR" is to
      be used when the dynamic rate cannot be supported (one case is,
      e.g., gateway to H.320).  "CBR" is mostly used for gateways to
|     circuit switch networks.  Therefore, the "CBR" is the rate not
      including any FEC as specified in Section 4.3.1.  If FEC is to be
|     used, the "b=" parameter MUST be used to allow the extra bitrate
      needed to send the redundant information.  [...]

Corrected Text
--------------
   CBR:  Constant Bitrate (CBR) indicates the exact codec bitrate in
      bits per second (not including the overhead from packetization,
      RTP header, or lower layers) that the codec MUST use.  "CBR" is to
      be used when the dynamic rate cannot be supported (one case is,
      e.g., gateway to H.320).  "CBR" is mostly used for gateways to
|     circuit switched networks.  Therefore, the "CBR" is the rate not
      including any FEC as specified in Section 4.3.1.  If FEC is to be
|     used, the "b=" SDP parameter MUST be used to allow the extra
      bitrate needed to send the redundant information.  [...]

Notes
-----
Rationale:

a)  Typo;  s/circuit switch/circuit switched/

b)  In the context of the discussion of media type parameters,
    also using the unqualified term "parameter" for an SDP parameter
    is rather confusing; for clarity, "SDP" needs to be inserted.

Instructions:
-------------
This errata is currently posted as "Reported". If necessary, please
use "Reply All" to discuss whether it should be verified or
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RFC5404 (draft-ietf-avt-rtp-g719-04)
--------------------------------------
Title               : RTP Payload Format for G.719
Publication Date    : January 2009
Author(s)           : M. Westerlund, I. Johansson
Category            : PROPOSED STANDARD
Source              : Audio/Video Transport
Area                : Real-time Applications and Infrastructure
Stream              : IETF
Verifying Party     : IESG
_______________________________________________
Audio/Video Transport Working Group
[email-masked]
https://www.ietf.org/mailman/listinfo/avt

---

From: Magnus Westerlund <[email-masked]>
Date: Tue, 27 Jan 2009 10:55:20 +0100

Hi,

I agree that the text is wrong, but it doesn't point out the correct
solution in my mind. The correct one would be so not talk about SDP
parameters at all. Instead the text should discuss the need to indicate
that the session bandwidth is different from the value the CBR parameter
provides when any type of FEC or redundancy is used.

In general I think there is little risk that anyone reading this RFC and
that they completely lack knowledge about SDP. If you do, then sure, it
is somewhat confusing. But I don't think there is any risk for any
interoperability issues due to this.

I see two possible solutions:

1. Reclassify the errata as editorial and put it in hold for update.

2. Reject this one and submit another that is intended to describe what
should be done and put that in hold for update.

Cheers

Magnus

-- 

Magnus Westerlund

IETF Transport Area Director & TSVWG Chair
----------------------------------------------------------------------
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]
----------------------------------------------------------------------
_______________________________________________
Audio/Video Transport Working Group
[email-masked]
https://www.ietf.org/mailman/listinfo/avt

---

From: RFC Editor <[email-masked]>
Date: Tue, 27 Jan 2009 12:09:09 -0800

Hi Magnus,

The ADs have the ability to edit the errata entry.  I think it would
be cleaner if you were to supply the correct text to the ADs and allow
them to update the entry, as opposed to rejecting one and creating a
new one.  Also, notes can be added to the report to explain how/why
the original entry was altered.

Please let us know if you have any questions!

Thanks!

Sandy

---

From: Magnus Westerlund <[email-masked]>
Date: Wed, 28 Jan 2009 11:29:43 +0100

AVT,

Definitely a reminder about the importance to remove some addresses when
sending email. I am well aware of the process about the Erratas, and
sending it to RFC-editor has little function unless one have a question
to them particularly.

The guidelines for how to judge the Erratas are published here:
http://www.ietf.org/IESG/STATEMENTS/iesg-statement-07-30-2008.txt

It is actually the responsible AD that performs the actions that
confirms, rejects or modifies the Errata in the RFC-editors system. As
an AD I know that you don't want to do that without the feedback from
the authors and/or WG-chairs. It is also important for any errata that
are of technical nature or have technical implication that there is
consensus about them. Thus allowing time for people provide input.

In this case I will narrow it done to one suggestion:

Edit the errata it in the following way:

1. Re-classify as Editorial

2. Add in the Note:

c) (From Authors) This text should probably not talk about SDP
parameters at all, but rather the need for external functionality that
indicates the actual bitrate of the RTP session as due to the
FEC/Redundancy the CBR value is not a good indicator of the total bitrate.

3. Put it in Hold for Document Update state.

Cheers

Magnus

RFC Editor skrev:
>> F�r�gatan 6                | Mobile +46 73 0949079

-- 

Magnus Westerlund

---

From: Magnus Westerlund <[email-masked]>
Date: Wed, 28 Jan 2009 14:07:13 +0100

Alfred � skrev:
> [[ further cutting down the distribution list ]]
> 
> Magnus,
> thanks for the update ...
> 
>> ...
>>
>> In this case I will narrow it down to one suggestion:
>>
>> Edit the errata in the following way:
>>
>> parameters at all, but rather the need for external functionality
>> that indicates the actual bitrate of the RTP session as due to the
> All three options are orthogonal and hence could in principle
> be applied independently.
> 
> After awareness has been gained now, I will not oppose to
> any part of this suggestion.
> 
> However, it should be noted that the definition of an
> "Editorial Erratum" is fuzzy; the RFC Editor once defined it as
> "could have been caught by a non-technical professional editor".
> With respect to that definition, part 1 above would be questionable
> w.r.t. the main part of the erratum (Note b)).
> 

Alfred,

Yes, I do agree that the border is fuzzy. If looking at the current
guidance on the RFC-editor page it says an editorial is:
"a spelling, grammar, punctuation, or syntax error that does not affect
the technical meaning"

So in this case I think the classification depends on who you think the
reader is. For anyone having some knowledge on the area it is classified
as editorial, but if this is your first document in the whole of RAI you
read, then yes technical.

So, anything goes in this regards. I think the Hold for Update is the
correct state as it is very unlikely that it causes confusion. If other
think that I recommend that they speak up and I will be easily swayed.

cheers

Magnus Westerlund

---

From: Alfred Hönes <[email-masked]>
Date: Wed, 28 Jan 2009 13:39:15 +0100 (MEZ)

Magnus,

Kind regards,
  Alfred.

-- 

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