From owner-freebsd-net@FreeBSD.ORG Sun Mar 2 14:00:53 2008 Return-Path: Delivered-To: net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0B77A10656F1 for ; Sun, 2 Mar 2008 14:00:52 +0000 (UTC) (envelope-from wjw@digiware.nl) Received: from mail.digiware.nl (www.tegenbosch28.nl [217.21.251.97]) by mx1.freebsd.org (Postfix) with ESMTP id F07B48FC1C for ; Sun, 2 Mar 2008 14:00:51 +0000 (UTC) (envelope-from wjw@digiware.nl) Received: from localhost (localhost.digiware.nl [127.0.0.1]) by mail.digiware.nl (Postfix) with ESMTP id 9CCC81736C; Sun, 2 Mar 2008 14:37:58 +0100 (CET) X-Virus-Scanned: amavisd-new at digiware.nl Received: from mail.digiware.nl ([127.0.0.1]) by localhost (rack1.digiware.nl [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id YqpPJuoz2wBK; Sun, 2 Mar 2008 14:37:56 +0100 (CET) Received: from [192.168.2.10] (unknown [192.168.2.10]) by mail.digiware.nl (Postfix) with ESMTP id 7381F1715A; Sun, 2 Mar 2008 14:37:56 +0100 (CET) Message-ID: <47CAADB8.9000202@digiware.nl> Date: Sun, 02 Mar 2008 14:38:00 +0100 From: Willem Jan Withagen Organization: Digiware User-Agent: Thunderbird 2.0.0.12 (Windows/20080213) MIME-Version: 1.0 To: Barney Cordoba , Ingo Flaschberger , net@freebsd.org References: <497111.42659.qm@web63905.mail.re1.yahoo.com> <20080301225727.GA85851@owl.midgard.homeip.net> In-Reply-To: <20080301225727.GA85851@owl.midgard.homeip.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Subject: Re: FBSD 1GBit router? X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 02 Mar 2008 14:00:53 -0000 Erik Trulsson wrote: >> Ok, well I've never seen a router with 1 port. I >> thought we were talking about building a router? > > He did not say anything about a single port router. > He talked about single port network cards. You can > use more than one of them when building a router. Well lets nitpick. A router does not have to have 2 ports. 2 examples: - routing between VLANs on the same interface - when doing routing in an overlay network. EG. in a connecting VPN networks I'm looking for a stream exploder.:) 1 2Mbit stream in, and as many as possible out. And 7*1Gb = 14Gbit, so I'd like to be pushing 7000 streams. (One advantage is that they will be UDP streams, so there is a little less bookkeeping in the protocol stack ) >> The lack of PCIe cards is a good reason to consider a >> PCIX machine. > > What lack of PCI-E cards? These days there are quite a > few to choose between. I'm under the impression that PCI-E is the way to go. Especially if I look at what is implemented on the more serious server boards. >> On the systems that we have, the 1x PCIe >> ports are a lot slower than a PCI-X card in the slot. >> >> You need 4Gb/s of throughput to handle a gigablt >> router. (1 GB/s full duplex times 2). 1x is 4Gb/s >> maximum. In my view, you always need twice the >> bandwidth on the bus to avoid contention issues. > > What contention issues? With PCI-E each device is essentially on its own > bus and does not need to contend with other devices for bandwidth on that > bus. Right, in PCI-E the lanes are just a star network into a hub. Now there is always going to be a bottleneck in a network. So here the big chance is that this is between the CPU and the hub. To see that just complete the above math: 7000 stream @ 2mbit/sec =~> 1.25E6 p/s =~> 1,75 Gb/sec Where all datatransport has to go over the processor. Well I have not seen systems with this as Frontside bus, so this is going to require a carefully crafted design. :) --WjW