Re: [tsvwg] [Ecn-sane] Comments on L4S drafts

Sebastian Moeller <moeller0@gmx.de> Fri, 19 July 2019 22:04 UTC

Return-Path: <moeller0@gmx.de>
X-Original-To: tsvwg@ietfa.amsl.com
Delivered-To: tsvwg@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 8D3BC120071 for <tsvwg@ietfa.amsl.com>; Fri, 19 Jul 2019 15:04:13 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.349
X-Spam-Level:
X-Spam-Status: No, score=-2.349 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, FREEMAIL_ENVFROM_END_DIGIT=0.25, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=gmx.net
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 mrV2hJw2ly_f for <tsvwg@ietfa.amsl.com>; Fri, 19 Jul 2019 15:04:10 -0700 (PDT)
Received: from mout.gmx.net (mout.gmx.net [212.227.17.20]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 5B4E1120018 for <tsvwg@ietf.org>; Fri, 19 Jul 2019 15:04:10 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1563573839; bh=YUOplZXpjJZ64FkSw5t4xxTSJQ8BdA+RTPEv5bSoHXQ=; h=X-UI-Sender-Class:Subject:From:In-Reply-To:Date:Cc:References:To; b=kcwBH/j7aoVzCU7pgWvYJ3pz1URojp49VtQW3ICQ1oTGeUaEjMufFwfgeubjRfxSC SFi83G43MVvvx8Pe4p1uzRHrr/zMhjqLlaDsAZDvkWusjYhdX91E1p7CBIxCxKLax/ +/86y8EUib23+ZiHM7wcdcYQSxKlBf/Azh0iT8xw=
X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c
Received: from hms-beagle2.lan ([77.185.86.147]) by mail.gmx.com (mrgmx105 [212.227.17.168]) with ESMTPSA (Nemesis) id 1MQMuX-1i27d0125R-00MOC2; Sat, 20 Jul 2019 00:03:59 +0200
Content-Type: text/plain; charset="us-ascii"
Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.11\))
From: Sebastian Moeller <moeller0@gmx.de>
In-Reply-To: <803D9CA8-220E-4F98-9B8E-6CE2916C3100@gmail.com>
Date: Sat, 20 Jul 2019 00:03:57 +0200
Cc: "Black, David" <David.Black@dell.com>, "tsvwg@ietf.org" <tsvwg@ietf.org>, "ecn-sane@lists.bufferbloat.net" <ecn-sane@lists.bufferbloat.net>, Dave Taht <dave@taht.net>, "De Schepper, Koen (Nokia - BE/Antwerp)" <koen.de_schepper@nokia-bell-labs.com>
Content-Transfer-Encoding: quoted-printable
Message-Id: <0079BC6B-4792-48ED-90D3-D9A69407F316@gmx.de>
References: <364514D5-07F2-4388-A2CD-35ED1AE38405@akamai.com> <4aff6353-eb0d-b0b8-942d-9c92753f074e@bobbriscoe.net> <D13294C4-105C-4F58-A762-6911A21A18C6@akamai.com> <CAH8sseSQaCbknok--hf=DgwzCs3OnnkKjPy5bdLgnzjq7-+c_w@mail.gmail.com> <ce4b1e2d-3bc8-265c-6bcd-5a26b4dd89e9@bobbriscoe.net> <1238A446-6E05-4A55-8B3B-878C8F39FC75@gmail.com> <AM4PR07MB3459B1173917DAFBCEB25511B9FA0@AM4PR07MB3459.eurprd07.prod.outlook.com> <17B33B39-D25A-432C-9037-3A4835CCC0E1@gmail.com> <AM4PR07MB345956F52D92759F24FFAA13B9F50@AM4PR07MB3459.eurprd07.prod.outlook.com> <52F85CFC-B7CF-4C7A-88B8-AE0879B3CCFE@gmail.com> <AM4PR07MB3459B471C4D7ADAE4CF713F3B9F60@AM4PR07MB3459.eurprd07.prod.outlook.com> <D231681B-1E57-44E1-992A-E8CC423926B6@akamai.com> <AM4PR07MB34592A10E2625C2C32B9893EB9F00@AM4PR07MB3459.eurprd07.prod.outlook.com> <A6F05DD3-D276-4893-9B15-F48E3018A129@gmx.de> <AM4PR07MB3459487C8A79B1152E132CE1B9CB0@AM4PR07MB3459.eurprd07.prod.outlook.com> <87ef2myqzv.fsf@taht.net> <a85d38ba-98ac-e43e-7610-658f4d03e0f4@mti-systems.com> <CE03DB3D7B45C245BCA0D243277949363062879C@MX307CL04.corp.emc.com> <803D9CA8-220E-4F98-9B8E-6CE2916C3100@gmail.com>
To: Jonathan Morton <chromatix99@gmail.com>
X-Mailer: Apple Mail (2.3445.104.11)
X-Provags-ID: V03:K1:okjs3RPvoZ2KB+bCMlQ8AIRMjprGKYbGR+S+QOZqxnPrd3gWwmW uNjNtOWDK0l6BWDmv6KFAte6rFBVjA9BbybAWT70gI8PpsLbQTFHLUdv4MzKT98UkhRF13o DpSUilfeSg60ccLopqk09Z0hUxTpJYFb84UKSHoPp/cY8jgjMcO2CRPq1+jNX0+65vFq/sw 1poOPpie2bXFetUz9o7XA==
X-UI-Out-Filterresults: notjunk:1;V03:K0:LRzIrVf6SSw=:Ubj0umJyXLdl2owbtUimnv 9S12qFuVPUDHyC37IKKBMReXa08VO6ApuXh+RDD49oaTlRYcJDKwpNBkkhD0ze1aWnCTQDe11 XIRFVOWZwSzSvhXJTuCFoMQwYbp3uO+HJK361hOVIgMLuAE6nSh5VZSgb5oeYmLm4CDzbLcGB UZ7CDh5F8EJnpHR9eteiYH88ac8NSBsuF1M6yXhnoJq3r7Jwjuec/kdj1ydrQytRiX0q8ZH0X 6rLHSWjB3ni6JjyETftA6n9r+0kITKWjxe8fb4c3O1STazTluCV/RFkSIzbWikZQfXHWHGGUo 8ocxvPCCqlmh4jMgd12OytvCBsOtjJ97M3bAvWYM2eataQxac20aSANh2NSrr7BC/TYtigPBb SPx+AO7iSf+yevnWBjJS/6b7X6J9RAOVO3R8de/VZvAxh+C6t6dedFiDu4GbEy2AqfU0J/MGy tPs7YwCzEPm7q60TIgsnw7j1HBYIlheDKn+ta4Q/GeQV6yQ5XkGmZsNSE8Nq9/4WJBT3wJAbj aGeKNJ5OIlT37KhZrP4OUzMv1wuOIB7nrfzMZxk9bdOOknSe29FyGC2E8QJW5KqhIctr09eYe ObclzZiMiim3IRAWhTCAFwOI6JHfSKOj8n5smExhpOJMnu4FJb6iHNyp+pEvIVJrJGj2TEZ1I 7/zsCDVloJZKB5x4+dMspC6pZGekSblaB7OpImfuM8nkiLmEp9zGYSTA1FNEzwcSDM4CPPYdO N6mxD8jVtv+3U48sMc1QsAMDOldVcEcXp5ftLyixJh54Onv9gY/4liQgE8qmAVai6mPEBy+HA kYBA8U1puXSyswe6HMH4mHx3lTr0MSVIJ2KuOwYymbAwgBrV3Cn6EyCzqCAMu69pC2Hk51uW2 jCrRuwpuDuUzvcpYRsbxN62fG8ntUq9/WP5xKxryJqT7GVWCMcSx15npr4AW28GcKIlNaWw3q NRb06Dp5B56WP+B7caoFB5twF9d61fD3o2MY6Mj0wOQ7c+5wHmEZxZ2rh+IEJo4iRGGO44TFv nTK6ClnAOgjeLHmo7ZQL6yo95Iik27HYMkHILbhvE5C+90yxGe1Kt331+jJLAQyl2pt+KgaoC hX5fuBFz19Id1o=
Archived-At: <https://mailarchive.ietf.org/arch/msg/tsvwg/T5E3Gm_4RaqenC88L2giGY3Rfk4>
Subject: Re: [tsvwg] [Ecn-sane] Comments on L4S drafts
X-BeenThere: tsvwg@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Transport Area Working Group <tsvwg.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/tsvwg>, <mailto:tsvwg-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/tsvwg/>
List-Post: <mailto:tsvwg@ietf.org>
List-Help: <mailto:tsvwg-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/tsvwg>, <mailto:tsvwg-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 19 Jul 2019 22:04:13 -0000

Hi Jonathan,



> On Jul 19, 2019, at 22:44, Jonathan Morton <chromatix99@gmail.com> wrote:
> 
>> On 19 Jul, 2019, at 4:06 pm, Black, David <David.Black@dell.com> wrote:
>> 
>> To be clear on what I have in mind:
>> 	o Unacceptable: All traffic marked with ECT(1) goes into the L4S queue, independent of what DSCP it is marked with.
>> 	o Acceptable:  There's an operator-configurable list of DSCPs that support an L4S service - traffic marked with ECT(1) goes into the L4S queue if and only if that traffic is also marked with a DSCP that is on the operator's DSCPs-for-L4S list.
> 
> I take it, in the latter case, that this increases the cases in which L4S endpoints would need to detect that they are not receiving L4S signals, but RFC-3168 signals.  The current lack of such a mechanism therefore remains concerning.  For comparison, SCE inherently retains such a mechanism by putting the RFC-3168 and high-fidelity signals on different ECN codepoints.
> 
> So I'm pleased to hear that the L4S team will be at the hackathon with a demo setup.  Hopefully we will be able to obtain comparative test results, using the same test scripts as we use on SCE, and also insert an RFC-3168 single queue AQM into their network to demonstrate what actually happens in that case.  I think that the results will be illuminating for all concerned.

	What I really would like to see, how L4S endpoints will deal with post-bottleneck ingress shaping by an RFC3168 -compliant FQ-AQM. I know the experts here deems this not even a theoretical concern, but I really really want to see data, that L4S flows will not crowd out the more reactive RFC3168 flows in that situation. This is the set-up quite a number of latency sensitive end-users actually use to "debloat" the internet and it would be nice to have real data showing that this is not a concern.

Best Regards
	Sebastian



> 
> - Jonathan Morton
> _______________________________________________
> Ecn-sane mailing list
> Ecn-sane@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/ecn-sane