Re: [tsvwg] L4S status: #17 Interaction w/ FQ AQMs

"alex.burr@ealdwulf.org.uk" <alex.burr@ealdwulf.org.uk> Thu, 07 November 2019 12:54 UTC

Return-Path: <alex.burr@ealdwulf.org.uk>
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 0E38712080D for <tsvwg@ietfa.amsl.com>; Thu, 7 Nov 2019 04:54:52 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.118
X-Spam-Level:
X-Spam-Status: No, score=-1.118 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_NEUTRAL=0.779, URIBL_BLOCKED=0.001] autolearn=no autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=yahoo.com
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 7T3PJLyjeJxW for <tsvwg@ietfa.amsl.com>; Thu, 7 Nov 2019 04:54:50 -0800 (PST)
Received: from sonic311-13.consmr.mail.bf2.yahoo.com (sonic311-13.consmr.mail.bf2.yahoo.com [74.6.131.123]) (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 E15ED12003F for <tsvwg@ietf.org>; Thu, 7 Nov 2019 04:54:49 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1573131288; bh=69e28KlgWobsWmyLuB7wURwNkGPA5muEFvh+O+BJDDo=; h=Date:From:Reply-To:To:Cc:In-Reply-To:References:Subject:From:Subject; b=aNF7O5fr1f3AO4W+0kIjHIFW6xf2XZbcDpsRR3xbZrmLdIN3yh1UA5Zv4G8TADvbxUB4pG7vSXwZ+dIjHGhZTzF/T6PAissBjeWv160zH5SGeo2nn247aV1oaXYkCUxRjC5XpfhQ02IZNiRy0vcmu1BnnIFKRwLTdR72AVDLirpwp7GXJfH7fSnZyeP0MCp7UnleFOKTH4eGfxZg1uvoY5LyxhpJt2RFzyE5yVdJ8pqQD+ozT97P1LMGMM5gM+fu8ytJyN1GDrxpIOk7TjMoL6Cs+oqwq0G3YO0sBA8beZbT7r+XZYqAtcdqp/0UUofUFINVV2VTa9J6zIo60XSezw==
X-YMail-OSG: k45L4esVM1mTKqYmWiiibcxOMgj3A3k0dhbeWn8MLPwTd0PyfMihmnVv9jk3Yr5 zoHxSrMUwXlfS_ZRKZHFfv.28x6YlSrX5G_BrL4DhRgdqcqINUkMD2KGu44pr6ZLrLMDfcsbFB0f ALxUQK_Mn1APA6diRby529WzLfA82W.gf.Mk0i6BtiWJ1TNLnHc3gAkZ9U_TOwGOKN83eLvfXzF. iONy5vgsAb_yPmQINaTLORo_9qmHoBmarcJuBuTZTeKt9syQl4yLOtllnO7XN1N.Je6jKCCaF7St oHbkfJslK0aE5a5Hje1k2F7FsAe34bHC.ezBkf_4.26le45y0b.G4SdFeRHM0VT0OXyWvrNyC8iB loRaq4Y1npNOsM3pgCYXzhgw7Fwt_JUMCxmICm6LYMrOtPV13CP_3pGnLQG_lBoLJXsqnZsoAlwq bS87I97lp96w97MYHz1VIr0xLx5sdW1jNYlZcGzZdG9bxVaRXxEAzHjzE9cgB8UplXcTH5uqPCrE woPe99Yh4VwKiPwc4wa3UqRVcvz26GtCItKE6cd4oQq0GjCz2KWxr4tABnpN6ZJ8nnMm8rAn5HRY loTiduZK4hz0qvRnBMW1q_E5snd__8MetzlFvmvb43B74if3ImpX063NYaqxg5azZB0wyIsm1wbR v1LMC9QzD3AstQDbGhrSDPUnT8aCI8AN7r_tPUPOcTQJI3tUWq7bwD5.2945O9hWEW2DnuLa8r_w 6Cs.usXhYioDoA69dcbNxAUKz59JyQJcmshw.kqdIvQ205O06geE.ReWaCGrMbboNabn5.96FgEe bI7szltBA9qjogVQDr0aLUMtyTJy.vnBYPhndPMfoXVZbgg1tQEqA6nRGkf5P7tgrtZ5tkASp00P vwk1XbQWVVl4SK2PyC7oYO27CpBpiOPabpBeqL96.0H9.ik7_eG5ZoK38TD.jlpCp5Y5reY0TK_3 7OHsi8pugqdCS2jReuyzafPZ4nFLS8wp9GIYMulE7AjeJ3bZ0D81WhJvpqnXLSEb7n1qEhPLp7AH O1pz_BvVSDeRJBur18rNJKKYEIJiJsw__VxjlZ2nrFhuYttI6orOX2c8u8EQC9XalTQgIOyARYBq keciGWBd6kCNYuljCJ6_K6r1QL7Rqd72Wsx43gGkgmv8sGzKktzYXeMyp9oUIDd148WQbIjVU18W KIdgFEHphDwA54iHB_ZySNjxHL7TYaInmpbRn5v.ZKbwg_sV1QPdJNQXusUSyt71L0BWubsGB_U. DzY.523GSzfpPm2BLETaFh3LAzpn5rU.6ksAX.vGXZrifHYVsuPYMoSjPR51AcXzSq8PQumC4FCx oqa5.21dHJmzlLrFo2J1f7b5UUJCKfjW78ylNevy8L3wa4ySsab5iP1jOYD5PuTdftDi4WXRFhp7 g_n4fJti.UXxqHtc-
Received: from sonic.gate.mail.ne1.yahoo.com by sonic311.consmr.mail.bf2.yahoo.com with HTTP; Thu, 7 Nov 2019 12:54:48 +0000
Date: Thu, 7 Nov 2019 12:54:44 +0000 (UTC)
From: "alex.burr@ealdwulf.org.uk" <alex.burr@ealdwulf.org.uk>
Reply-To: "alex.burr@ealdwulf.org.uk" <alex.burr@ealdwulf.org.uk>
To: Greg White <g.white@cablelabs.com>, Jonathan Morton <chromatix99@gmail.com>
Cc: "tsvwg@ietf.org" <tsvwg@ietf.org>
Message-ID: <1053591400.593303.1573131284597@mail.yahoo.com>
In-Reply-To: <090EDC6E-7B69-401D-931D-E9C3101E68DD@gmail.com>
References: <8321f975-dfe7-694c-b5cc-09fa371b9b61@mti-systems.com> <B58A5572-510E-42C7-8181-42A0BE298393@gmail.com> <D2E12331-F504-4D5F-B8E7-A1A5E98DDF7E@cablelabs.com> <2275E6A5-C8F8-477F-A24A-3E6168917DDF@gmail.com> <55F724CD-6E74-40D9-8416-D1918C2008DD@cablelabs.com> <BBE7C7A9-0222-4D84-BF27-8D5CAE2F995E@gmail.com> <6f189711-ffa0-90f4-fd16-3464ba4df3ce@mti-systems.com> <4A706B11-3239-4DAC-BE85-0B4BFF2D8FF8@heistp.net> <8B28ECE4-FF4B-4BB2-ACBE-80B30708F97E@cablelabs.com> <AAEA9AC2-B8A1-4837-A7C9-8EEA21A7C523@gmx.de> <D5D560CB-BC47-45BE-811E-E73E2D4909E3@cablelabs.com> <090EDC6E-7B69-401D-931D-E9C3101E68DD@gmail.com>
MIME-Version: 1.0
Content-Type: multipart/alternative; boundary="----=_Part_593302_236510020.1573131284596"
X-Mailer: WebService/1.1.14680 YMailNorrin Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Firefox/68.0
Archived-At: <https://mailarchive.ietf.org/arch/msg/tsvwg/I6QID-i2zflBlWiVtNUxcSCgHK0>
Subject: Re: [tsvwg] L4S status: #17 Interaction w/ FQ AQMs
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: Thu, 07 Nov 2019 12:54:52 -0000

 

    On Thursday, November 7, 2019, 3:35:06 AM GMT, Jonathan Morton <chromatix99@gmail.com> wrote:  

> > - if the CoDel queue is upgraded to perform Immediate AQM on L4S flows, the latency spike can be largely avoided.

> This is not relevant, since the point of this exercise is to establish the extent of L4S' compatibility with existing, unmodified networks, in which Codel happens to be the most widely deployed > AQM.  You cannot reasonably expect the entire Internet to "upgrade" to L4S compatible AQMs before you can safely begin deployment.

I wonder if Codel actually is the most widely deployed AQM. This is not to dispute your point, which is correct - proposing an update to Codel doesn't addess existing deployments.It's just that I'm aware that there is an awful lot of kit out there which has an implementation of RED (or WRED) in hardware - eg for TR-059 [1], which mandates WRED support in BRAS. That's from having worked at a silicon vendor, so it doesn't give me visibility of actual usage. I understand a lot of it isn't switched on, but if even a small fraction of it was, it would be a pretty big deployment. It would be interesting if anyone has actual numbers. .  Of course, to be relevant to this discussion, it would need to be configured to do ECN marking as well. 

[1] https://www.broadband-forum.org/technical/download/TR-059.pdf
Alex