From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lb0-f171.google.com (mail-lb0-f171.google.com [209.85.217.171]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 7F469200252; Tue, 13 Mar 2012 09:09:43 -0700 (PDT) Received: by lbbge1 with SMTP id ge1so599333lbb.16 for ; Tue, 13 Mar 2012 09:09:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; bh=VtXg1FDqFcqtgz+Q9zvj9lzr7cIQqwfiLqWyTyAkU5w=; b=M4T8dhNq7KLNPzx8i5hw8AVQqOf5LnITH6AuuK/q+wARN1f8ur1WfGfViiXUYAH26J uKSWDi6FZjviqST3sVNbB+LvOGy/mb0Vj4VvcUTIp59HotKYiWCwW2D1KcEXvL58YDBa Ljj5jHbiwbtWaIei/jlBJauN9dyG2UfjHAS7Zo+Xyz70aESPlLY40Bh6OdxGTn3QNGyS lor6cD/iF3rPeCD/4wcHUR9yA3QPy26D588A0hvijDBZWDiCuiX9AZJ04D6mPe69yJPR C5nlju4gNJlKlLnUPOfvMqiEaAIC5rkBKnRJmMK/0kcCn/aPBOF9oihn2Gxt07NBGFyE yqXg== MIME-Version: 1.0 Received: by 10.112.104.37 with SMTP id gb5mr6268612lbb.97.1331654981106; Tue, 13 Mar 2012 09:09:41 -0700 (PDT) Received: by 10.112.59.10 with HTTP; Tue, 13 Mar 2012 09:09:41 -0700 (PDT) In-Reply-To: References: Date: Tue, 13 Mar 2012 16:09:41 +0000 Message-ID: From: Dave Taht To: tz Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Cc: Steve Bauer , thumbgps-devel@lists.bufferbloat.net, cerowrt-devel@lists.bufferbloat.net, bismark-devel@projectbismark.net Subject: Re: [Thumbgps-devel] data collection X-BeenThere: thumbgps-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 13 Mar 2012 16:09:44 -0000 On Tue, Mar 13, 2012 at 3:21 PM, tz wrote: > One thing to note - a traceroute or something similar might be > necessary if we are measuring the network. ['s timekeeping ability] I was planning on traceroutes between peers. One the projects I track (and participated in until I got more busy 'fixing' the internet than diagnosing it) is projectbismark.net. Of late they've been adding diagnostic tools and a test framework, in lua, that can run on this router, they also have some interesting tools such as ditg and shaperprobe. I haven't been paying close attention, but there have been quite a few commits in their repositories of late. https://github.com/bismark-devel What I've been trying to do with cerowrt is establish a solid base for edge network exploration and experimentation, and I hope the upcoming release is going to do that. After that stablizes I hope to be able to start layering the so= rts of tools we're discussing here, on top of it, and know to what extent the results will be heisenbugged or not. > I'm down the street from Level 3, but use Comcast, and a Verizon mifi, > so packets are going to take different routes. Heh. I recently (accidentally) introduced a equal cost multipath situation on my testbed in bloatlab #1... except that of the two different paths, one had forwarding performance of 260Mbit, the other >800mbit. Was REALLY puzzling to figure that one out. (basically IPv6 was doing equal cost multipath, IPv4 was not) > The GPS location is one thing, but a backbone map would also be > relevant if not required. I liked the possible usage of the geoip database(s) combined with postgres's geography extension, to try and get baseline values for individual hops, vs reality, over time. There are other network tomography tools of interest at CAIDA. Good suggestions requested. I love visualizations like the ones from the cybergeography project http://personalpages.manchester.ac.uk/staff/m.dodge/cybergeography/atlas/ge= ographic.html http://www.wand.net.nz/scamper is of interest, I note that this version of cerowrt has full iptables support for ecn over ipv6, and that was one of the things that is thoroughly fixed in Linux-3.3 - or so I hope - and works measurably better than non-ecn based AQM methods. Steve Bauer over at MIT did a whole bunch of ECN tests last year, I hope he (or someone) can build upon that work. I'd looked hard at perfsonar only to note that it wasn't measuring anything I cared about, and was based on an ancient kernel. I'd like to look at it again to see what it isn't measuring, and to see what it is mis-measuring. And while I'm on the subject of visualisations, gource is just an amazing way to look at commit logs.... http://code.google.com/p/gource/wiki/Videos showing projects evolve. > One thing which might help is if a major backbone vendor (cisco, arbor > networks) would adopt this technology into one of their high-end > switches. =A0They probably do something similar already to get somewhat I note that bufferbloat.net is co-located with isc.org, which is also where ntp.org is located... one of our servers is about 18 inches away from their rack. > accurate time, but perhaps without the precision and they typically > aren't running stratum 1 servers on or a hop from the backbones which > might be the most interesting. I would certainly like to see time made more accurate world wide. > > On Tue, Mar 13, 2012 at 10:55 AM, Dave Taht wrote: >> But back to the network mapping front, one reason I'd chosen postgres >> for a backend was the geography support, being able to calculate in >> curves seemed like a good idea. I'm curious if anybody has other >> thoughts for a backend to a global time slew database? --=20 Dave T=E4ht SKYPE: davetaht US Tel: 1-239-829-5608 http://www.bufferbloat.net