From owner-freebsd-net@FreeBSD.ORG Fri Jan 21 23:01:13 2005 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 C73AF16A4CE for ; Fri, 21 Jan 2005 23:01:13 +0000 (GMT) Received: from drumandbass.at (drumandbass.at [62.116.16.204]) by mx1.FreeBSD.org (Postfix) with ESMTP id 700BC43D31 for ; Fri, 21 Jan 2005 23:01:12 +0000 (GMT) (envelope-from chaoztc@confusion.at) Received: (qmail 99101 invoked from network); 21 Jan 2005 23:01:10 -0000 Received: from unknown (HELO drumandbass.at) (62.116.16.204) by drumandbass.at with SMTP; 21 Jan 2005 23:01:10 -0000 Date: Sat, 22 Jan 2005 00:01:10 +0100 (CET) From: Ingo X-X-Sender: To: In-Reply-To: <20050121195050.GA2866@odin.ac.hmc.edu> Message-ID: <20050121235344.E93890-100000@ix.reflection.at> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Subject: Re: [PATCH] 802.1p priority (fixed) 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: Fri, 21 Jan 2005 23:01:13 -0000 Hi, > My concern is that 802.1p is like the TOS bits in that it differentiates > packets within a network rather then segregating them in to networks > like 802.1Q. In a switch it makes sense to handle priorities as separate > networks, but I'm not sure it makes sense in a host. If nothing else, > it seems to make sense to be able to set priorities on vlan encapsulated > frames. In an Isp backbone I trust 802.1Q packets because no customer has access to tagged vlan connections. Trusting in TOS bit is in such a network no good idea because every customer could send IP traffic. And overwriting the TOS bit at all network edges could be a pain to not miss some edges. 802.1Q is some kind of "out of band" QOS for IP. L2 Ethernet switches could also handle 802.1Q but not the TOS bits in the IP header. bye, Ingo