From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from tuna.sandelman.ca (tuna.sandelman.ca [IPv6:2607:f0b0:f:3::184]) by huchra.bufferbloat.net (Postfix) with ESMTP id 4FD3721F1F3 for ; Fri, 11 Oct 2013 20:18:13 -0700 (PDT) Received: from sandelman.ca (desk.marajade.sandelman.ca [209.87.252.247]) by tuna.sandelman.ca (Postfix) with ESMTP id 50C5920273; Sat, 12 Oct 2013 00:28:25 -0400 (EDT) Received: by sandelman.ca (Postfix, from userid 179) id E813163B88; Fri, 11 Oct 2013 23:18:05 -0400 (EDT) Received: from sandelman.ca (localhost [127.0.0.1]) by sandelman.ca (Postfix) with ESMTP id D7A1863B87; Fri, 11 Oct 2013 23:18:05 -0400 (EDT) From: Michael Richardson To: "Eggert\, Lars" In-Reply-To: References: X-Mailer: MH-E 8.2; nmh 1.3-dev; GNU Emacs 23.4.1 X-Face: $\n1pF)h^`}$H>Hk{L"x@)JS7<%Az}5RyS@k9X%29-lHB$Ti.V>2bi.~ehC0; <'$9xN5Ub# z!G,p`nR&p7Fz@^UXIn156S8.~^@MJ*mMsD7=QFeq%AL4m Sender: mcr@sandelman.ca Cc: "Akhtar, Shahid \(Shahid\)" , "iccrg@irtf.org" , "aqm@ietf.org" , bloat Subject: Re: [Bloat] [iccrg] [aqm] AQM deployment status? 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: Sat, 12 Oct 2013 03:18:13 -0000 --=-=-= Eggert, Lars wrote: > I've heard that statement [that RED is supported] from many different > people. I wonder if it is > actually true. Is there any hard data on this? The issue I've had is that while RED is supported on a routing device, and I can enable it on a per-VLAN basis, that does me little good, because there are bottlenecks in layer-2 devices (ethernet, but also DSL,GPON, etc.) which are out of my control. What I would like is a standard layer-3 way to measure bandwidth across my layer-3 hop, and autoconfigure RED (or CoDel) to the measured bandwidth. My understanding is that some equipment can use 802.1ad CCP and/or Loopback frames to measure bandwidth across bridged layer-2 ethernet networks. I'm unclear if this is a feature of that equipment, or a part of the standard. My understanding is that the math involved is pretty straightforward, but getting it right in code can involve dealing with a number of numerical issues which makes it slightly non-trivial to implement. (And you need good low-latency time stamping of packets) -- Michael Richardson , Sandelman Software Works --=-=-= Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQCVAwUBUli/bYqHRg3pndX9AQItSQQA4LSYBoUP5+xivrh2v0A8hW8qNB9ULmJX hXGK3TSYv5dXslVbxt90uFv3dyaOgxltpuT2pP4uxcH6LBk6m/jXraL3lBthqWfF pUKkq60iZYmCRYLaYBzMA3BWtVq7Vt9nY+GcWZtOUODQJvJnXQdAcSfLLY7r73N/ X2e24Y8eZaI= =FnNZ -----END PGP SIGNATURE----- --=-=-=--