From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-la0-f98.google.com (mail-la0-f98.google.com [209.85.215.98]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id B2F9D21F1FE for ; Mon, 27 Apr 2015 04:03:37 -0700 (PDT) Received: by labmn9 with SMTP id mn9so2196690lab.0 for ; Mon, 27 Apr 2015 04:03:35 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:content-type:mime-version:subject:from :in-reply-to:date:cc:content-transfer-encoding:message-id:references :to; bh=H9dyFy43bdnyPq5px71uz2dIPhXyOVkpcp+dkcA0Yag=; b=HQ6mSEd8CKdnNEo0JU+223K/5+xF1ThpKHRgmtyrndM3vghixOyHiusc9GEOar4vfN 88n3ME6iL/NMP8PeIYzrgyxIujH59WTFS842D5aqJnLuAMelhlEiIMBTaWGCu2QhkAHm R2gJepvqrl7dafAXJBjSLH3OfyYQw7buD87RBVCPJgjEb8txZbY8yxBrHzKnsGBgX1Dk hbuw+dnMSVSkOUObJ43gGWUUTrNl9sdAGnjB9zoLi7ayT5js164Nmr8xEWabeb4VrcQD nawpmJkc2mFJeXzVz8Nd7Dh5ax5D8RFdQzd4vHvYF5ovy2PmNPNihB+2av1BoTYiFBdW xfig== X-Gm-Message-State: ALoCoQllNlaqB2EHcBNS2sSSsJEroMlLiOtQkv7ngjRTvfo7htXH1DIoj92WiezaNZ2xdZ08AN8CWabOa168ViuTL5Yjyc4joQ== X-Received: by 10.194.184.146 with SMTP id eu18mr20874846wjc.94.1430132615259; Mon, 27 Apr 2015 04:03:35 -0700 (PDT) Received: from mail.la.pnsol.com (eu1sys200aog123.obsmtp.com. [207.126.144.155]) by mx.google.com with SMTPS id eh5sm353635wib.3.2015.04.27.04.03.34 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Mon, 27 Apr 2015 04:03:35 -0700 (PDT) X-Relaying-Domain: pnsol.com Received: from mail.la.pnsol.com ([89.145.213.110]) (using TLSv1) by eu1sys200aob123.postini.com ([207.126.147.11]) with SMTP ID DSNKVT4XhbquPhDK+NchGQd7g394XzlHEY4G@postini.com; Mon, 27 Apr 2015 11:03:34 UTC Received: from git.pnsol.com ([172.20.5.238] helo=roam.smtp.pnsol.com) by mail.la.pnsol.com with esmtp (Exim 4.76) (envelope-from ) id 1Ymgp0-0001W6-LG; Mon, 27 Apr 2015 12:03:30 +0100 Received: from [172.20.5.110] by roam.smtp.pnsol.com with esmtpsa (TLS1.0:RSA_AES_128_CBC_SHA1:128) (Exim 4.82) (envelope-from ) id 1Ymgoq-00008G-FA; Mon, 27 Apr 2015 11:03:20 +0000 Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) From: Neil Davies In-Reply-To: <87383l3ktd.fsf@toke.dk> Date: Mon, 27 Apr 2015 12:03:35 +0100 Content-Transfer-Encoding: quoted-printable Message-Id: References: <87r3r53ncb.fsf@toke.dk> <04A0C729-6E87-49C6-84F7-3428F236CA15@unimore.it> <3DC1A2EA-6DDD-4FF9-AD12-BB509EFB96B8@unimore.it> <30560030-8A86-481D-A310-B3B72C26C368@pnsol.com> <87fv7l3lqo.fsf@toke.dk> <1E4513D8-FAEB-4D51-969E-093FA4929D89@pnsol.com> <87383l3ktd.fsf@toke.dk> To: =?windows-1252?Q?Toke_H=F8iland-J=F8rgensen?= X-Mailer: Apple Mail (2.1878.6) Cc: bloat Subject: Re: [Bloat] Detecting bufferbloat from outside a node X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 27 Apr 2015 11:04:06 -0000 On 27 Apr 2015, at 11:52, Toke H=F8iland-J=F8rgensen = wrote: > Neil Davies writes: >=20 >> The interesting thing is making all those local decisions add up to a >> (set of) end-to-end outcomes, and the answer is not to make the same >> decision(s) everywhere - unfortunately that doesn=92t stack up. >=20 > Yes, well, I do also like the E2E principle of not making too many > decisions within the network, instead letting the endpoints sort it = out. > For me, the fight against bufferbloat is mostly about restoring the > assumptions that it has eroded (i.e. "packet loss is not to be feared, > but on the contrary is an important indicator that we're hitting > congestion"). I'd really rather prefer the network itself to be fairly > dumb... I don't think that the E2E principle can manage the emerging performance hazards that are arising. We've seen this recently in practice: take a = look at http://www.martingeddes.com/how-far-can-the-internet-scale/ - it is = based on a real problem we'd encountered. In someways this is just control theory 101 rearing its head... in = another it is a large technical challenge for internet provision. >> We have (some level) of control over our =93universe of discourse=94 = - my >> joke with my mates at CERN is that they only have one universe to >> investigate, we can create three in one day and still be home in time >> for tea! >=20 > Hehe, quite. That is both fascinating and frustrating! :) >=20 > -Toke