From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from web.heavenlysanctuary.com (web.heavenlysanctuary.com [74.80.207.230]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 671E53B29D for ; Fri, 14 Jan 2022 02:43:00 -0500 (EST) Received: from [192.168.10.101] (unknown [47.145.161.70]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by web.heavenlysanctuary.com (Postfix) with ESMTPSA id 4JZtZC29RMz5DlX4; Thu, 13 Jan 2022 23:42:59 -0800 (PST) Message-ID: <71621958-4d38-8f05-31d8-995cfc01d458@heavenlysanctuary.com> Date: Thu, 13 Jan 2022 23:42:59 -0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.4.1 Content-Language: en-US To: Dave Taht Cc: bloat References: <334460f8-89e7-0ca8-75b8-edbdf30e7961@heavenlysanctuary.com> From: Marco Belmonte In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-1.0 required=3.0 tests=ALL_TRUSTED,SHORTCIRCUIT shortcircuit=ham autolearn=disabled version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on web.heavenlysanctuary.com Subject: Re: [Bloat] ONTs and ITU - T G.988 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: Fri, 14 Jan 2022 07:43:00 -0000 Well, I for one will be most interesting in watching your progress and am available if you need samples (500 Mb Fiber - Frontier FIOS). Marco On 1/12/2022 4:57 PM, Dave Taht wrote: > What appeared to be the case was that a ONT had a 50ms buffer at > 100Mbit and was reconfigured to drive a gig and thus only had 5ms. > > At least, that's what the data looked like. This was on a fairly > recent reddit thread a month or two back, that I cannot find right > now. I'm pretty sure it was in the context of eero's > rolling out a working htb+fq_codel implementation finally for the eero > 6, (or maybe it was the comcast AQM?0 and us discovering it didn't do > any good, that the ont was seemingly brutally underbuffered, which > took days of scratching my head.... multiple flent tests... wish I > could find that thread... > > This is kind of ironic, but the structure of the speedtest (8+ flows > with short RTTs) actually could lead naturally to buffers that short > and few would notice. > > Anyway, that sparked me finally going and reading up a bit more about > how ONTs work... > > > On Wed, Jan 12, 2022 at 4:40 PM Marco Belmonte > wrote: >> Dave, >> >> Can you describe to me what under buffered would look like? Let's say >> I'm playing Rocket League on a Frontier FIOS connection... When a >> situation arises where the connection is under buffered you might see >> _____. >> >> A lot of interrupts being generated? connections timing out? lag? >> >> I'm guessing that many of the same symptoms that accompanying buffer >> bloat also manifest themselves with buffer bleed? >> >> Marco >> >> >> On 1/12/2022 3:42 PM, Dave Taht wrote: >>> Up until this point I haven't cared all that much about fiber, as most >>> of my observations were that it had "reasonable" buffering and all I >>> could hold in my head was the 802.11 standards. Since cablemodems are >>> well on their way to being fixed, wifi is looking good, and I recently >>> came across an ONT that was actually underbuffered, my holiday reading >>> consisted of pounding through a ton of fiber specs like this one: >>> >>> https://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-G.988-201711-I!!PDF-E&type=items >>> >>> There's a lot of promising info in this spec starting from page 104. >>> >>> My 1st question is - are there any ONTs that actually do do pause >>> frames? Or providers that configure for them? >>> >>> My second is - what is a cheap way to setup a lab to emulate a good, >>> common, version of gpon e2e? >>> >>> Third - what OS do these things run? Who makes a "good" one? >>> >> _______________________________________________ >> Bloat mailing list >> Bloat@lists.bufferbloat.net >> https://lists.bufferbloat.net/listinfo/bloat > >