From owner-freebsd-net@FreeBSD.ORG Tue Mar 2 07:27:34 2004 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 15B5016A4CE for ; Tue, 2 Mar 2004 07:27:34 -0800 (PST) Received: from mailtoaster1.pipeline.ch (mailtoaster1.pipeline.ch [62.48.0.70]) by mx1.FreeBSD.org (Postfix) with ESMTP id 362EF43D39 for ; Tue, 2 Mar 2004 07:27:33 -0800 (PST) (envelope-from andre@freebsd.org) Received: (qmail 57433 invoked from network); 2 Mar 2004 15:27:32 -0000 Received: from unknown (HELO freebsd.org) ([62.48.0.53]) (envelope-sender ) by mailtoaster1.pipeline.ch (qmail-ldap-1.03) with SMTP for ; 2 Mar 2004 15:27:32 -0000 Message-ID: <4044A7E4.B109121B@freebsd.org> Date: Tue, 02 Mar 2004 16:27:32 +0100 From: Andre Oppermann X-Mailer: Mozilla 4.76 [en] (Windows NT 5.0; U) X-Accept-Language: en MIME-Version: 1.0 To: Ian Smith References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit cc: freebsd-net@freebsd.org Subject: Re: My planned work on networking stack X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 02 Mar 2004 15:27:34 -0000 Ian Smith wrote: > > [-current out of ccs, I'm not subscribed] > > On Tue, 2 Mar 2004, Andre Oppermann wrote to Wes Peters: > > > > Wowsers. I can't wait to hear more. When do you expect to have a design > > > for the ARP stuff and TCP buffer sizing, since they are underway? > > > > The ARP stuff is pretty simple and is a hash list IP->MAC per ethernet > > (actually 802.1) broadcast domain. The harder part is to move all the > > code to one place from it's various net/* and netinet/* files. As a > > nice side effect we get per-MAC accounting (octets, frames) for free. > > What about bridged interfaces that have a MAC, but no IP address? I'm > still trying to figure this one out for a (4.8-R) bridge that's working > fine but still has some issues with ARP confusion and thus repeated ARP > requests from the upstream / outside router, esp regarding broadcast UDP > traffic, where the inside interface has the one IP and thus broadcast > address, for broadcast packets delivered locally to the bridge's IP? ARP will only be there if an IP address is configured on a interface. A bridge doesn't need any ARP for its bridging functionality, it is just relaying a frame from one side to the other. To do that it maintains a table with MAC addresses it sees on the particitpating interfaces. But that is entirely unreated to ARP which only does IP->MAC mappings. > I realise this is a bridge issue, but it's how it interacts with ARP. > > The rest of this is well out of my league, but fascinating reading :) -- Andre