Re: [aqm] Question re draft-baker-aqm-recommendations recomendation #2

Linda Dunbar <linda.dunbar@huawei.com> Mon, 29 April 2013 14:46 UTC

Return-Path: <linda.dunbar@huawei.com>
X-Original-To: aqm@ietfa.amsl.com
Delivered-To: aqm@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 76EB621F9E31 for <aqm@ietfa.amsl.com>; Mon, 29 Apr 2013 07:46:59 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -6.372
X-Spam-Level:
X-Spam-Status: No, score=-6.372 tagged_above=-999 required=5 tests=[BAYES_00=-2.599, RCVD_IN_DNSWL_MED=-4, SARE_SUB_OBFU_Q1=0.227]
Received: from mail.ietf.org ([12.22.58.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id gzdMh3muC5hc for <aqm@ietfa.amsl.com>; Mon, 29 Apr 2013 07:46:59 -0700 (PDT)
Received: from lhrrgout.huawei.com (lhrrgout.huawei.com [194.213.3.17]) by ietfa.amsl.com (Postfix) with ESMTP id 120D321F9E2C for <aqm@ietf.org>; Mon, 29 Apr 2013 07:46:57 -0700 (PDT)
Received: from 172.18.7.190 (EHLO lhreml203-edg.china.huawei.com) ([172.18.7.190]) by lhrrg02-dlp.huawei.com (MOS 4.3.5-GA FastPath queued) with ESMTP id AQX30562; Mon, 29 Apr 2013 14:46:56 +0000 (GMT)
Received: from LHREML405-HUB.china.huawei.com (10.201.5.242) by lhreml203-edg.huawei.com (172.18.7.221) with Microsoft SMTP Server (TLS) id 14.1.323.7; Mon, 29 Apr 2013 15:46:07 +0100
Received: from DFWEML405-HUB.china.huawei.com (10.193.5.102) by lhreml405-hub.china.huawei.com (10.201.5.242) with Microsoft SMTP Server (TLS) id 14.1.323.7; Mon, 29 Apr 2013 15:46:52 +0100
Received: from DFWEML509-MBX.china.huawei.com ([169.254.11.204]) by dfweml405-hub.china.huawei.com ([10.193.5.102]) with mapi id 14.01.0323.007; Mon, 29 Apr 2013 07:46:45 -0700
From: Linda Dunbar <linda.dunbar@huawei.com>
To: "Fred Baker (fred)" <fred@cisco.com>, "aqm@ietf.org" <aqm@ietf.org>
Thread-Topic: Question re draft-baker-aqm-recommendations recomendation #2
Thread-Index: AQHOROHZhsCdSNtJ20a8tgniU6d8dpjtQ7NQ
Date: Mon, 29 Apr 2013 14:46:44 +0000
Message-ID: <4A95BA014132FF49AE685FAB4B9F17F645B1521D@dfweml509-mbx.china.huawei.com>
References: <8C48B86A895913448548E6D15DA7553B82A5E5@xmb-rcd-x09.cisco.com>
In-Reply-To: <8C48B86A895913448548E6D15DA7553B82A5E5@xmb-rcd-x09.cisco.com>
Accept-Language: en-US, zh-CN
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-originating-ip: [10.192.11.224]
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-CFilter-Loop: Reflected
Subject: Re: [aqm] Question re draft-baker-aqm-recommendations recomendation #2
X-BeenThere: aqm@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: "Discussion list for active queue management and flow isolation." <aqm.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/aqm>, <mailto:aqm-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/aqm>
List-Post: <mailto:aqm@ietf.org>
List-Help: <mailto:aqm-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/aqm>, <mailto:aqm-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 29 Apr 2013 14:46:59 -0000

Generally agree with signaling to an endpoint using both dropping and ECN, except ECN marking may not be possible in MPLS networks because MPLS ECN uses EXP bits that are used to mark Priority in many deployed networks. 

I think that it is important to emphasize that ECN marking for end points to notify source nodes don't work well in very large networks. 

Since today's network is tunnels over tunnels (multiple layers of tunnels, e.g. MPLS over PW),  the tunnel scoped ECN marking can work well if the outmost tunnel doesn't go over too many hops and subsequent tunnels control the ingress rate. 
 

Linda Dunbar

> -----Original Message-----
> From: aqm-bounces@ietf.org [mailto:aqm-bounces@ietf.org] On Behalf Of
> Fred Baker (fred)
> Sent: Monday, April 29, 2013 9:00 AM
> To: aqm@ietf.org
> Subject: [aqm] Question re draft-baker-aqm-recommendations
> recomendation #2
> 
> Do we generally agree with the recommendation of
> http://tools.ietf.org/html/draft-baker-aqm-recommendation-01#section-
> 4.2? This is the question of signaling to an endpoint using both
> dropping and ECN.
> 
> 
> _______________________________________________
> aqm mailing list
> aqm@ietf.org
> https://www.ietf.org/mailman/listinfo/aqm