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

Dave Taht <dave@taht.net> Sat, 20 July 2019 21:03 UTC

Return-Path: <dave@taht.net>
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 31A151201CA for <tsvwg@ietfa.amsl.com>; Sat, 20 Jul 2019 14:03:06 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.899
X-Spam-Level:
X-Spam-Status: No, score=-1.899 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] 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 T0CsBNYgi80O for <tsvwg@ietfa.amsl.com>; Sat, 20 Jul 2019 14:03:04 -0700 (PDT)
Received: from mail.taht.net (mail.taht.net [176.58.107.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id E17CD1201A0 for <tsvwg@ietf.org>; Sat, 20 Jul 2019 14:03:03 -0700 (PDT)
Received: from dancer.taht.net (unknown [IPv6:2603:3024:1536:86f0:eea8:6bff:fefe:9a2]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.taht.net (Postfix) with ESMTPSA id 9E4FD221EC; Sat, 20 Jul 2019 21:03:00 +0000 (UTC)
From: Dave Taht <dave@taht.net>
To: Sebastian Moeller <moeller0@gmx.de>
Cc: Jonathan Morton <chromatix99@gmail.com>, "Black, David" <David.Black@dell.com>, "tsvwg@ietf.org" <tsvwg@ietf.org>, "ecn-sane@lists.bufferbloat.net" <ecn-sane@lists.bufferbloat.net>, "De Schepper, Koen (Nokia - BE/Antwerp)" <koen.de_schepper@nokia-bell-labs.com>
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> <0079BC6B-4792-48ED-90D3-D9A69407F316@gmx.de>
Date: Sat, 20 Jul 2019 14:02:48 -0700
In-Reply-To: <0079BC6B-4792-48ED-90D3-D9A69407F316@gmx.de> (Sebastian Moeller's message of "Sat, 20 Jul 2019 00:03:57 +0200")
Message-ID: <871rykzafb.fsf@taht.net>
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux)
MIME-Version: 1.0
Content-Type: text/plain
Archived-At: <https://mailarchive.ietf.org/arch/msg/tsvwg/A2Hg3Wcs6SQ284SwwaFQe54lW-M>
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: Sat, 20 Jul 2019 21:03:06 -0000

Sebastian Moeller <moeller0@gmx.de> writes:

> 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.

+10

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