Re: [xrblock] SDP Directorate review of draft-ietf-xrblock-rtcp-xr-discard

Jonathan Lennox <jonathan@vidyo.com> Tue, 18 December 2012 15:18 UTC

Return-Path: <jonathan@vidyo.com>
X-Original-To: xrblock@ietfa.amsl.com
Delivered-To: xrblock@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 8D27D21F8A2F; Tue, 18 Dec 2012 07:18:23 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.47
X-Spam-Level:
X-Spam-Status: No, score=-2.47 tagged_above=-999 required=5 tests=[AWL=0.129, BAYES_00=-2.599]
Received: from mail.ietf.org ([64.170.98.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id avbXS4+mII9u; Tue, 18 Dec 2012 07:18:23 -0800 (PST)
Received: from mxout.myoutlookonline.com (mxout.myoutlookonline.com [64.95.72.243]) by ietfa.amsl.com (Postfix) with ESMTP id D6ACE21F892E; Tue, 18 Dec 2012 07:18:22 -0800 (PST)
Received: from mxout.myoutlookonline.com (localhost [127.0.0.1]) by mxout.myoutlookonline.com (Postfix) with ESMTP id 039A24169C8; Tue, 18 Dec 2012 04:16:54 -0500 (EST)
X-Virus-Scanned: by SpamTitan at mail.lan
Received: from HUB015.mail.lan (unknown [10.110.2.1]) by mxout.myoutlookonline.com (Postfix) with ESMTP id 245F24169E4; Tue, 18 Dec 2012 04:16:53 -0500 (EST)
Received: from BE235.mail.lan ([10.110.32.235]) by HUB015.mail.lan ([10.110.17.15]) with mapi; Tue, 18 Dec 2012 10:18:18 -0500
From: Jonathan Lennox <jonathan@vidyo.com>
To: Qin Wu <bill.wu@huawei.com>, Glen Zorn <gwz@net-zen.net>
Date: Tue, 18 Dec 2012 10:18:12 -0500
Thread-Topic: SDP Directorate review of draft-ietf-xrblock-rtcp-xr-discard
Thread-Index: Ac3cxkH92ClQKy5JQAuJd73gbsI7bwAbGDzQ
Message-ID: <C3759687E4991243A1A0BD44EAC823034DFB915EF7@BE235.mail.lan>
References: <C3759687E4991243A1A0BD44EAC823034DFB915B07@BE235.mail.lan> <50CFCBF9.3070301@net-zen.net> <A4AC6E76F05F423DA11BFB0DCE52FE0C@china.huawei.com>
In-Reply-To: <A4AC6E76F05F423DA11BFB0DCE52FE0C@china.huawei.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
acceptlanguage: en-US
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-Mailman-Approved-At: Tue, 18 Dec 2012 07:27:41 -0800
Cc: "xrblock@ietf.org" <xrblock@ietf.org>, "draft-ietf-xrblock-rtcp-xr-discard@tools.ietf.org" <draft-ietf-xrblock-rtcp-xr-discard@tools.ietf.org>, "mmusic@ietf.org" <mmusic@ietf.org>, "gwz@net-zen.net" <gwz@net-zen.net>
Subject: Re: [xrblock] SDP Directorate review of draft-ietf-xrblock-rtcp-xr-discard
X-BeenThere: xrblock@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: Metric Blocks for use with RTCP's Extended Report Framework working group discussion list <xrblock.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/xrblock>, <mailto:xrblock-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/xrblock>
List-Post: <mailto:xrblock@ietf.org>
List-Help: <mailto:xrblock-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/xrblock>, <mailto:xrblock-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 18 Dec 2012 15:18:23 -0000

Yes, that text addition seems reasonable to me.

For people experienced with XRBlocks, Glen's point that this isn't confusing is taken; but I think this addition would be helpful for those (like me) who are coming to this somewhat cold.

Sorry for the typo in the RFC number.

-----Original Message-----
From: Qin Wu [mailto:bill.wu@huawei.com] 
Sent: Monday, December 17, 2012 9:20 PM
To: Glen Zorn; Jonathan Lennox
Cc: mmusic@ietf.org; draft-ietf-xrblock-rtcp-xr-discard@tools.ietf.org; gwz@net-zen.net; xrblock@ietf.org
Subject: Re: SDP Directorate review of draft-ietf-xrblock-rtcp-xr-discard

I guess the reference "RFC3711 section 5" Jonathan mentioned should be corrected as "RFC3611 section 5".
If my understanding is correct, what Jonathan suggested is to have the following change:
OLD TEXT:
"
   RFC 3611 defines the use of SDP (Session Description Protocol)
   [RFC4566] for signaling the use of RTCP XR blocks.  XR blocks MAY be
   used without prior signaling.

"
NEW TEXT:
"
   RFC 3611 defines the use of SDP (Session Description Protocol)
   [RFC4566] for signaling the use of RTCP XR blocks.  However XR blocks MAY be
   used without prior signaling (see section 5 of RFC3611).
"
Please correct me if I am wrong.

Regards!
-Qin
----- Original Message ----- 
From: "Glen Zorn" <gwz@net-zen.net>
To: "Jonathan Lennox" <jonathan@vidyo.com>
Cc: <mmusic@ietf.org>; <draft-ietf-xrblock-rtcp-xr-discard@tools.ietf.org>; <gwz@net-zen.net>
Sent: Tuesday, December 18, 2012 9:50 AM
Subject: Re: SDP Directorate review of draft-ietf-xrblock-rtcp-xr-discard


> On 12/17/2012 10:49 PM, Jonathan Lennox wrote:
> 
>> I have been asked to perform  the SDP Directorate review for
> > draft-ietf-xrblock-rtcp-xr-discard. I reviewed the -10 version of the
> > document.
> >
> >
> >
> > Syntactically, the SDP usage in this document seems fine. It is a
> > simple and correct usage of an extension point defined in RFC 3711.
> >
> >
> >
> > However, the statement in Section 4 that "XR blocks MAY be used
> > without explicit signaling" is confusing, as it implies that the
> > entire SDP section is entirely optional. This document should at
> > least reference Section 5 of RFC 3711, which gives guidance as to
> > when SDP signaling of the use of XR blocks is recommended.
> >
> 
> I'm not sure why this is confusing (aside from fact that RFC 3711 is 
> itself confusing: it says "although the use of SDP signaling for XR 
> blocks may be optional, if used, it MUST be used as defined here". /May/ 
> be optional?  Optionality seems pretty black and white to me ;-).  That 
> said, however, it does seem to be relatively clear that the usage of SDP 
> /is/ optional & along with it the section on SDP in this and other 
> similar drafts.  What am I missing?
> 
> ...
>