From owner-freebsd-net@FreeBSD.ORG Fri Jul 13 20:31:10 2007 Return-Path: X-Original-To: freebsd-net@freebsd.org Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id EAD0016A404 for ; Fri, 13 Jul 2007 20:31:10 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from mail-out4.apple.com (mail-out4.apple.com [17.254.13.23]) by mx1.freebsd.org (Postfix) with ESMTP id D0E3F13C48E for ; Fri, 13 Jul 2007 20:31:10 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from relay6.apple.com (relay6.apple.com [17.128.113.36]) by mail-out4.apple.com (Postfix) with ESMTP id C7628BEDA1E; Fri, 13 Jul 2007 13:31:10 -0700 (PDT) Received: from relay6.apple.com (unknown [127.0.0.1]) by relay6.apple.com (Symantec Mail Security) with ESMTP id B3F821008E; Fri, 13 Jul 2007 13:31:10 -0700 (PDT) X-AuditID: 11807124-a5fb9bb0000007f3-64-4697e10e37e3 Received: from [17.214.13.96] (int-si-a.apple.com [17.128.113.41]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by relay6.apple.com (Apple SCV relay) with ESMTP id A161E1006A; Fri, 13 Jul 2007 13:31:10 -0700 (PDT) In-Reply-To: <4697DF64.9070203@seclark.us> References: <46967C5C.5040505@seclark.us> <469772DA.1000700@gmail.com> <46977741.8090301@seclark.us> <20070713093408.b8a92c23.wmoran@collaborativefusion.com> <4697A60C.4090409@seclark.us> <20070713130402.ed2f79ce.wmoran@collaborativefusion.com> <20070713180840.GB8392@verio.net> <20070713152725.6ae40056.wmoran@collaborativefusion.com> <4697DF64.9070203@seclark.us> Mime-Version: 1.0 (Apple Message framework v752.2) Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Message-Id: Content-Transfer-Encoding: 7bit From: Chuck Swiger Date: Fri, 13 Jul 2007 13:31:10 -0700 To: Stephen.Clark@seclark.us X-Mailer: Apple Mail (2.752.2) X-Brightmail-Tracker: AAAAAA== Cc: freebsd-net@freebsd.org Subject: Re: 6.2 mtu now limits size of incomming packet 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: Fri, 13 Jul 2007 20:31:11 -0000 On Jul 13, 2007, at 1:24 PM, Stephen Clark wrote: >> Designers of gateways should be prepared for the fact that >> successful >> gateways will be copied and used in other situation and >> installations. Gateways must be prepared to accept datagrams as >> large as can be sent in the maximum packets of the directly >> attached >> networks. > > Doesn't this imply if a gateway has 2 interfaces, one with an mtu > of 1280 and the other > with an mtu of 1500 it should accept 1500 on either interface? Agreed-- if the traffic is going towards the network on the interface with the 1280 MTU, the gateway should accept and then either fragment such traffic or drop it, depending on whether DF is set. -- -Chuck