From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: 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 lists.bufferbloat.net (Postfix) with ESMTPS id 158B73B2A4 for ; Thu, 29 Nov 2018 05:15:31 -0500 (EST) Received: from [172.16.10.187] ([134.76.241.253]) by mail.gmx.com (mrgmx102 [212.227.17.168]) with ESMTPSA (Nemesis) id 0LpPg1-1fnBJc1dGX-00f8Ji; Thu, 29 Nov 2018 11:15:29 +0100 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 11.5 \(3445.9.1\)) From: Sebastian Moeller In-Reply-To: Date: Thu, 29 Nov 2018 11:15:27 +0100 Cc: Jonathan Morton , bloat Content-Transfer-Encoding: quoted-printable Message-Id: <2BDFF247-AF0E-452C-B1EA-2B143C6DD8F3@gmx.de> References: <65EAC6C1-4688-46B6-A575-A6C7F2C066C5@heistp.net> <38535869-BF61-4FC4-A0FB-96E91CC4F076@ifi.uio.no> <87va4gwe74.fsf@taht.net> <7125B446-F2C4-45B3-B48C-8720B1E35776@gmail.com> To: Mikael Abrahamsson X-Mailer: Apple Mail (2.3445.9.1) X-Provags-ID: V03:K1:Vv7uXwfFu3wBJBLok9lFLZM9pnpd/dZuelAbyX5qPnz9wxeddWc u7A2avpIsPiE73hBdP7lTXWbSb7yYyPesQtpE2EyyTRYn9CajjPGZYrT5sASx247A0s8Xhd kYMRM8pHgJMlaM9lo3GOi5Lv4I+762QeN5wlePkxqI7Clp38/5RIvBjeIWamlFFbAXtS8W7 di0gXA3Bk2VEnAbSpwW1A== X-Spam-Flag: NO X-UI-Out-Filterresults: notjunk:1;V03:K0:xdb7dbkWHC4=:JD0NJa3kIfND1huEnqgPma 6vr8uMKhLtQRTA0J375VoqiQVvtJ2PzZYg5UXwIV+k5rSmLoaMxt2l3I/ZpdwaB4HUILc191Y cnhycyv1o8DBFvyg8Gm4HTXJVnSbrhwo5tK7IXof6EOqsn3S9JR25LeF2+lZnewpJOGSV+NcJ G9NSoIESZUVPFNfevAte3F8Ri57R2M1YM5bIKKhy1z/GBh14ryVvrLUYCoTv626n+cUjx1fUt 2p9iIXHqP7osPmbE+eonV1mZuF9KnM0lPt5yquiYspbrXs8wBJOejmAOVjoN2qY6Yq1ka35zJ afcPcA3aPojPdJWod5WWUdO8Sj6JCMozrRQiJ7SUcWydLw+fc6W5nggdu7p7/PgQqXJH8Xzml CBaWAfTNgQgK7kWEK2ZYvNP94PoKTuF+UF3QuBQHsKOxqFtr00sGgPLeanAyatAowv8Fii7K8 3e6C/klgDWbUqiinYADwZ+O71Nv37zOezz4NV0XmYHzFuRqA75ttRM9Rhb2Hw0LP++37pu11g F5hGlK0LHWE2K//9rfjFHJb1qp5E2JHV8fxBasJZnkG8hskGkr+AkkRQvFDk8JSARFG8/mP5i 2GrACyGarWFWSJlc3Fhtbf9qZuiKyAkTdpHU/h8HP6k60wzBTGW8igGFMYOrqfIX1lPke7Hly esIUFsYiA5wNxv3hHfWY/lG+gTHJYDZI6FRXydTWL0lxJgTBvBoei/gY8B1Qo6zlLyGhjIwaW q+ouZdWB6GtChut1Pa5n/5Kg/paO0fsuu12HZm68B9cbaLHO+aeJBTHkBCfGAJO9VQS5CR9vw qu4N00Cpn2+LcTRz/VLNmt4wpAn64IQR83h5xRBMHCVOfWCdSSLJDyYLEtSjX0+7TlY3hY6X3 wXzs2B5JxrT+i47UN4ZV9pU59qOvmj2cdjpptIg7hpjNnC2ECO0z3hSPnsa0yE Subject: Re: [Bloat] incremental deployment, transport and L4S (Re: when does the CoDel part of fq_codel help in the real world?) X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 29 Nov 2018 10:15:32 -0000 Hi Mikael, > On Nov 29, 2018, at 08:46, Mikael Abrahamsson = wrote: >=20 > On Thu, 29 Nov 2018, Jonathan Morton wrote: >=20 >> You are essentially proposing using ECT(1) to take over an intended = function of Diffserv. >=20 > Well, I am not proposing anything. I am giving people a heads-up that = the L4S authors are proposing this. >=20 > But yes, you're right. Diffserv has shown itself to be really hard to = incrementally deploy across the Internet, so it's generally bleached = mid-path. >=20 >> In my view, that is the wrong approach. Better to improve Diffserv = to the point where it becomes useful in practice. >=20 > I agree, but unfortunately nobody has made me king of the Internet yet = so I can't just decree it into existance. With your kind of clue, I would happily vote you as (temporary) = king of the internet. ;) >=20 >> Cake has taken steps in that direction, by implementing some = reasonable interpretation of some Diffserv codepoints. >=20 > Great. I don't know if I've asked this but is CAKE easily = implementable in hardware? =46rom what I can tell it's still only = Marvell that is trying to put high performance enough CPUs into HGWs to = do forwarding in CPU (which can do CAKE), all others still rely on = packet accelerators to achieve the desired speeds. As far as I can tell intel is pushing atom/x86 cores into its = docsis SoCs (puma5/6/7) as well as into the high-end dsl SoCs (formerly = lantiq, = https://www.intel.com/content/www/us/en/smart-home/anywan-grx750-home-gate= way-brief.html?wapkw=3Dgrx750), I am quite confident that those also = pack enough punch for CPU based routing at Gbps-rates. In docsis modems = these are already rolled-out, I do not know of any DSL modem/router that = uses the GRX750 >=20 >> My alternative use of ECT(1) is more in keeping with the other = codepoints represented by those two bits, to allow ECN to provide more = fine-grained information about congestion than it presently does. The = main challenge is communicating the relevant information back to the = sender upon receipt, ideally without increasing overhead in the TCP/IP = headers. >=20 > You need to go into the IETF process and voice this opinion then, = because if nobody opposes in the near time then ECT(1) might go to L4S = interpretation of what is going on. They do have ECN feedback mechanisms = in their proposal, have you read it? It's a whole suite of documents, = architecture, AQM proposal, transport proposal, the entire thing. >=20 > On the other hand, what you want to do and what L4S tries to do might = be closely related. It doesn't sound too far off. >=20 > Also, Bob Briscoe works for Cable Labs now, so he will now have = silicon behind him. This silicon might go into other things, not just = DOCSIS equipment, so if you have use-cases that L4S doesn't do but might = do with minor modification, it might be better to join him than to fight = him. Call me naive, but the solution to the impasse at getting a common = definition of diffserv agreed upon is replacing all TCP CC algorithms? = This is replacing changing all endpoints (and network nodes) to honor = diffserve with changing all endpoints to use a different TCP CC. At = least I would call that ambitious.... (unless L4S offers noticeable = advantages for all participating without being terribly unfair to the = non-participating legacy TCP users*). Best Regards Sebastian *) Well, being unfair ad out-competing the legacy users would be the = best way to incentivize everybody to upgrade, but that would also be = true for a better diffserve scheme... >=20 > --=20 > Mikael Abrahamsson email: swmike@swm.pp.se > _______________________________________________ > Bloat mailing list > Bloat@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/bloat