From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net (mout.gmx.net [212.227.15.15]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (Client CN "mout.gmx.net", Issuer "TeleSec ServerPass DE-1" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 3D5CE21F206 for ; Thu, 19 Dec 2013 02:49:28 -0800 (PST) Received: from u-081-c036.eap.uni-tuebingen.de ([134.2.81.36]) by mail.gmx.com (mrgmx103) with ESMTPSA (Nemesis) id 0M1WHV-1VeG8z3QhF-00tXQr for ; Thu, 19 Dec 2013 11:49:24 +0100 Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 6.6 \(1510\)) From: Sebastian Moeller In-Reply-To: <31B5B61B-4E58-4C5E-8F33-710CCE0918F4@gmail.com> Date: Thu, 19 Dec 2013 11:49:26 +0100 Content-Transfer-Encoding: quoted-printable Message-Id: References: <34E77F64-739C-49E4-B8A4-6ABBEAE4174B@gmail.com> <8DB84101-C942-49C4-99F0-6C9319961297@gmail.com> <22176178-A50F-48F2-A3A1-D3853764AD0E@gmail.com> <0E267F91-3CC8-48F4-92C0-AD8BACA98FCC@gmail.com> <1FA2FD44-D715-4B50-BB5A-BAF61070970B@gmx.de> <31B5B61B-4E58-4C5E-8F33-710CCE0918F4@gmail.com> To: Rich Brown X-Mailer: Apple Mail (2.1510) X-Provags-ID: V03:K0:0LWVKT+ACET5p+FZ813au/aJhoKzYrorOviMHjH857G9KbQwJPf 7fWqU0U9IA53KpcP+UzvjZCnYwRZjtT+s8yxJ3z1xraRcVViXAcgB4bBndx6EYc9nEM5gDp 5xrHcD2Xb0oPSt1KHfhPEQCPfLn3ErUVeCPfcIbZFo7j/ddwm/JSRqqCn9Szw+y5H0rccMb pAF9X5ltxYEVYG/+PiA5w== Cc: cerowrt-devel@lists.bufferbloat.net Subject: Re: [Cerowrt-devel] cerowrt-3.10.24-5 dev build released X-BeenThere: cerowrt-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: Development issues regarding the cerowrt test router project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 19 Dec 2013 10:49:28 -0000 Hi Rich, On Dec 19, 2013, at 05:12 , Rich Brown wrote: > Hi Sebastian, >=20 >>> Perhaps we could extend the Interface configuration page to add a = =93Link uses DSL/ADSL:=94 checkbox right below the Protocol dropdown. = Default would be off, but when customers go to the GE00 interface to = enter their PPPoE/PPPoATM/ISP credentials, they=92d see this additional = checkbox. Checking it would feed that info to the AQM tab. (And perhaps = there could be a link there either to the AQM tab, or to the wiki for = more information.) >>=20 >> I am happy to include a link to a wiki, but I guess we first = need a wiki page :)=20 >=20 > Is this a challenge? Well, I accept! :-) >=20 > = http://www.bufferbloat.net/projects/cerowrt/wiki/Setting_up_AQM_for_CeroWr= t_310 is a draft. I recycled the images from a previous message and = wrote the least amount that I could that is likely to be true. This is great, thanks a lot. I have made a few changes to the = GUI yesterday, which hopefully improve the usability, so if the new GUI = passes muster with the cerowrt crowd, the screenshots will need to = change as you note on top. >=20 > Please send me comments (or edit the page directly, if you have = permissions.) I do not have edit permissions, so I just comments here. Basic settings: Why 85% as starting point? And can we give instructions how to = measure "degradation in performance", so that non-technical users have a = chance to actually optimize their own system? Queueing Discipline: Maybe we can add a link to the mail list page = (https://lists.bufferbloat.net/listinfo/cerowrt-devel)? Also can we note that it is recommended to turn ECN off for the = egress, as we handle packets before the bottleneck and dropping packets = actually allows us to send other more urgent packets , while on ingress = it is recommended to turn ECN on, as the packets have cleared the = bottleneck already, and hence dropping has no bandwidth advantage = anymore. Both dropping and ECN should have the same effect on TCP = adaptation to the path capacity. Link Layer Adaptation: I think the first question is: Do I have an ATM carrier between = your modem and your ISP's DSLAM? This typically is true for all ADSL = variants. The second question is: Do I have overhead on the link outside = of Ethernet framing? This typically is true for users of PPPoE and = PPPoATM and even Bridging I think. If the answer to any of these questions is yes, one needs to = activate the link layer adaptations.=20 In case of pure overhead select ethernet, in case of ADSL select = ATM. Fill in the per packet overhead in byte (see: = http://ace-host.stuart.id.au/russell/files/tc/tc-atm/, = http://web.archive.org/web/20100527024520/http://www.adsl-optimizer.dk/ = and http://www.faqs.org/rfcs/rfc2684.html). If the overhead truly is = zero and no ATM carrier is used, then select "none" for link layer = adaptation. (I changed this page, so the tc_stab htb_private selection = is under advanced options, and there is a selection of "none", = "ethernet", and "none" in the first drop down box, "none" disables the = link layer adaptation. Also the drop down box contains some information = which selection is relevant for which cases). What=92s going on here? Why do I need this?: I think we should mention that only with the proper link layer = selected and the overhead specified cerowrt is able to assess how large = each packet is on the link to the ISP, and only then the shaping is = deterministic. (For ATM users without the adaptations the shaper is = stochastically too optimistic about the link capacity (which is too say = the shaper is too optimistic about the effective packet sizes)). Best Regards Sebastian > Thanks. >=20 > Rich