IETF Logo Mail Archive

Re: [payload] draft-ietf-payload-flexible-fec-scheme-14 notes

"Roni Even (A)" <roni.even@huawei.com> Mon, 07 January 2019 11:30 UTC

Return-Path: <roni.even@huawei.com>
X-Original-To: payload@ietfa.amsl.com
Delivered-To: payload@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 174BF130EA2; Mon, 7 Jan 2019 03:30:54 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.59
X-Spam-Level:
X-Spam-Status: No, score=-2.59 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001, T_KAM_HTML_FONT_INVALID=0.01] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 95rt72qq2pJp; Mon, 7 Jan 2019 03:30:51 -0800 (PST)
Received: from huawei.com (lhrrgout.huawei.com [185.176.76.210]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 8E08C130E9F; Mon, 7 Jan 2019 03:30:51 -0800 (PST)
Received: from lhreml705-cah.china.huawei.com (unknown [172.18.7.107]) by Forcepoint Email with ESMTP id 76CE032B6608E5641A7F; Mon, 7 Jan 2019 11:30:48 +0000 (GMT)
Received: from DGGEMM424-HUB.china.huawei.com (10.1.198.41) by lhreml705-cah.china.huawei.com (10.201.108.46) with Microsoft SMTP Server (TLS) id 14.3.408.0; Mon, 7 Jan 2019 11:30:47 +0000
Received: from DGGEMM526-MBX.china.huawei.com ([169.254.8.137]) by dggemm424-hub.china.huawei.com ([10.1.198.41]) with mapi id 14.03.0415.000; Mon, 7 Jan 2019 19:30:43 +0800
From: "Roni Even (A)" <roni.even@huawei.com>
To: Magnus Westerlund <magnus.westerlund@ericsson.com>, Giridhar Mandyam <mandyam@qti.qualcomm.com>, "draft-ietf-payload-flexible-fec-scheme.all@ietf.org" <draft-ietf-payload-flexible-fec-scheme.all@ietf.org>, "payload@ietf.org" <payload@ietf.org>, Ben Campbell <ben@nostrum.com>
Thread-Topic: [payload] draft-ietf-payload-flexible-fec-scheme-14 notes
Thread-Index: AdSjpbyCoL1+LHhrRfypJF1xMdVwaQC1k/xA
Date: Mon, 07 Jan 2019 11:30:42 +0000
Message-ID: <6E58094ECC8D8344914996DAD28F1CCD18C99631@dggemm526-mbx.china.huawei.com>
References: <c98b67a013d94d1d9fe62504153b83b6@NASANEXM01C.na.qualcomm.com> <DB7PR07MB4988ED389E5D133A6806E6B895890@DB7PR07MB4988.eurprd07.prod.outlook.com>
In-Reply-To: <DB7PR07MB4988ED389E5D133A6806E6B895890@DB7PR07MB4988.eurprd07.prod.outlook.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-originating-ip: [10.200.202.77]
Content-Type: multipart/alternative; boundary="_000_6E58094ECC8D8344914996DAD28F1CCD18C99631dggemm526mbxchi_"
MIME-Version: 1.0
X-CFilter-Loop: Reflected
Archived-At: <https://mailarchive.ietf.org/arch/msg/payload/UF1S2p4CTDd2cJ_qfaBoiOCZ8mU>
Subject: Re: [payload] draft-ietf-payload-flexible-fec-scheme-14 notes
X-BeenThere: payload@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Audio/Video Transport Payloads working group discussion list <payload.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/payload>, <mailto:payload-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/payload/>
List-Post: <mailto:payload@ietf.org>
List-Help: <mailto:payload-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/payload>, <mailto:payload-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 07 Jan 2019 11:30:54 -0000

Hi Magnus,
This also what I thought specially the case of multiple sources.
Roni Even as Individual

From: Magnus Westerlund [mailto:magnus.westerlund@ericsson.com]
Sent: Monday, January 07, 2019 12:26 PM
To: Giridhar Mandyam; draft-ietf-payload-flexible-fec-scheme.all@ietf.org; payload@ietf.org; Ben Campbell
Subject: Re: [payload] draft-ietf-payload-flexible-fec-scheme-14 notes

Hi,

In regard to the below.

On 2019-01-03 21:50, Giridhar Mandyam wrote:

There are a couple of substantive changes based on AD review (versus version -13) of which the group should be aware:


  1.  Sec. 4.2.1.  Under the description of the SSRC field, the following requirement was previously a SHOULD:  ""The repair streams' SSRC's CNAME MUST be identical to the CNAME of the source RTP stream(s) that this repair stream protects."



There was actually a reason for this SHOULD. That should likely have been written out explicitly. In case of a RTP middlebox adding FEC to one or more streams it forwards towards to a downstream receiver or other middlebox then it can't use the CNAME of the source stream if there are multiple ones from different sources. Secondly, even if it forwards only from one, that SSRC sending the FEC stream probably shouldn't be required to give the impression that it is the source entity doing this. In some cases RTP middleboxes are considering doing this on behalf of the original source, but not always.

Thus, I am opposed to make this change. I rather add an exception statement after the SHOULD.

The repair streams' SSRC's CNAME SHOULD be identical to the CNAME of the source RTP stream(s) that this repair stream protects. An FEC stream that protects multiple source RTP streams with different CNAMEs uses the CNAME associated with entity generating the FEC stream or the CNAME of the entity on whose behalf it perform the protection operation.



Cheers



Magnus Westerlund



----------------------------------------------------------------------

Network Architecture & Protocols, Ericsson Research

----------------------------------------------------------------------

Ericsson AB                 | Phone  +46 10 7148287

Torshamnsgatan 23           | Mobile +46 73 0949079

SE-164 80 Stockholm, Sweden | mailto: magnus.westerlund@ericsson.com<mailto:magnus.westerlund@ericsson.com>

----------------------------------------------------------------------

v2.23.0 | Report a Bug | By Email