From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from uplift.swm.pp.se (ipv6.swm.pp.se [IPv6:2a00:801::f]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by huchra.bufferbloat.net (Postfix) with ESMTPS id B08FE201253 for ; Wed, 25 Sep 2013 12:24:59 -0700 (PDT) Received: by uplift.swm.pp.se (Postfix, from userid 501) id AA0DC9C; Wed, 25 Sep 2013 21:24:56 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by uplift.swm.pp.se (Postfix) with ESMTP id A401D9A; Wed, 25 Sep 2013 21:24:56 +0200 (CEST) Date: Wed, 25 Sep 2013 21:24:56 +0200 (CEST) From: Mikael Abrahamsson To: "iccrg@irtf.org" In-Reply-To: Message-ID: References: <20130925143510.GA6191@sesse.net> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) Organization: People's Front Against WWW MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: "aqm@ietf.org" , bloat Subject: Re: [Bloat] [aqm] [iccrg] 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: Wed, 25 Sep 2013 19:25:00 -0000 On Wed, 25 Sep 2013, Akhtar, Shahid (Shahid) wrote: > Please see below examples of support for RED/WRED from switches (from ALU and Cisco websites, search for RED or WRED in document): I'd venture to claim that putting RED on a device with a few milliseconds worth of buffer depth is pretty much useless (for instance the Cisco 6704 or 6724 linecards). So most datacenter equipment doesn't have this, or if they do, it's not that usable even if they had (who cares about drop probability when taildrop is being done at 4-5 ms buffer depth?). For higher end platforms, for instance all cisco CPU based routers (for some value of "all") can be configured with RED, fair-queue or similar, but they come with FIFO as default. This has been the same way since at least the mid 90ties as far as I know, long way back to cisco 1600 device etc. Higher end Cisco equipment such as ASR9k, 12000, CRS etc, all support WRED, and here it makes sense since they all have ~50ms worth of buffering or more. They also come with FIFO as default setting. -- Mikael Abrahamsson email: swmike@swm.pp.se