From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from onelab2.iet.unipi.it (onelab2.iet.unipi.it [131.114.59.238]) by huchra.bufferbloat.net (Postfix) with ESMTP id 355EF21F149; Wed, 10 Oct 2012 16:35:10 -0700 (PDT) Received: by onelab2.iet.unipi.it (Postfix, from userid 275) id 947AD7300A; Thu, 11 Oct 2012 01:55:28 +0200 (CEST) Date: Thu, 11 Oct 2012 01:55:28 +0200 From: Luigi Rizzo To: Stephen Hemminger Message-ID: <20121010235528.GA21987@onelab2.iet.unipi.it> References: <87d30rra1s.fsf@toke.dk> <507454AA.9060206@hp.com> <87mwzvphf1.fsf@toke.dk> <25234.1349911631@sandelman.ca> <20121010162911.5f2d14d4@nehalam.linuxnetplumber.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20121010162911.5f2d14d4@nehalam.linuxnetplumber.net> User-Agent: Mutt/1.4.2.3i Cc: Toke H?iland-J?rgensen , codel@lists.bufferbloat.net, Michael Richardson , bloat@lists.bufferbloat.net Subject: Re: [Codel] [Bloat] better testing, linux 3.6.1, cerowrt credits, other stuff X-BeenThere: codel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: CoDel AQM discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 10 Oct 2012 23:35:10 -0000 On Wed, Oct 10, 2012 at 04:29:11PM -0700, Stephen Hemminger wrote: > On Wed, 10 Oct 2012 19:27:11 -0400 > Michael Richardson wrote: > > > > > >> But: It became obvious fast that long RTT tests were needed, > > >> which I've been trying to establish the infrastructure to do > > > > toke> I assume that by "infrastructure" you mean "(netperf) servers > > toke> far away"? What would be needed for a test server in terms of > > toke> resources (bandwidth and otherwise)? I could try and persuade > > toke> my university to let me setup a test server on their network > > toke> (which is in Denmark)... > > > > I interpret the question to mean networks where is there significant > > actual delay along them. I seem to recall that there are some ways to > > do this Linux machines, but most commercial test equipment can simulate > > things, including dropping packets. > > I think, however, that we do not want/need and packets dropped, as then > > the bandwidth constraint would not be in the device under test. > > netem can do all the stuff commercial gear can. > In fact, it is used by one of the commercial products! similarly you can use ipfw+dummynet, it has been running on Linux and a variety of other OS for a long time, see http://info.iet.unipi.it/~luigi/dummynet/ cheers luigi