From owner-freebsd-net@FreeBSD.ORG Mon Jan 24 18:04:07 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 0D30816A4CE for ; Mon, 24 Jan 2005 18:04:07 +0000 (GMT) Received: from us.svf.stuba.sk (us.svf.stuba.sk [147.175.16.9]) by mx1.FreeBSD.org (Postfix) with ESMTP id 4B4C443D55 for ; Mon, 24 Jan 2005 18:04:06 +0000 (GMT) (envelope-from md@us.svf.stuba.sk) Received: from us.svf.stuba.sk (localhost [127.0.0.1]) by us.svf.stuba.sk (8.13.1/8.13.1) with ESMTP id j0OI41wc097081 for ; Mon, 24 Jan 2005 19:04:02 +0100 (CET) (envelope-from md@us.svf.stuba.sk) Received: (from md@localhost) by us.svf.stuba.sk (8.13.1/8.13.1/Submit) id j0OI3uWl097080 for freebsd-net@freebsd.org; Mon, 24 Jan 2005 19:03:56 +0100 (CET) (envelope-from md) Resent-Message-Id: <200501241803.j0OI3uWl097080@us.svf.stuba.sk> Received: from us.svf.stuba.sk (localhost [127.0.0.1]) by us.svf.stuba.sk (8.13.1/8.13.1) with ESMTP id j0OHsYC2096852; Mon, 24 Jan 2005 18:54:34 +0100 (CET) (envelope-from md@us.svf.stuba.sk) Received: (from md@localhost) by us.svf.stuba.sk (8.13.1/8.13.1/Submit) id j0OHsT5n096851; Mon, 24 Jan 2005 18:54:29 +0100 (CET) (envelope-from md) Date: Mon, 24 Jan 2005 18:54:29 +0100 From: Marian Durkovic To: Clark Gaylord Message-ID: <20050124175429.GA96355@us.svf.stuba.sk> References: <20050124160242.GA91593@us.svf.stuba.sk> <41F52B41.4090706@dirtcheapemail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <41F52B41.4090706@dirtcheapemail.com> User-Agent: Mutt/1.4.2.1i X-Virus-Scanned: ClamAV 0.80/648/Sun Jan 2 09:18:38 2005 clamav-milter version 0.80j on us.svf.stuba.sk X-Virus-Scanned: ClamAV 0.80/648/Sun Jan 2 09:18:38 2005 clamav-milter version 0.80j on us.svf.stuba.sk X-Virus-Status: Clean X-Virus-Status: Clean X-Spam-Status: No, hits=0.0 required=5.0 tests=none autolearn=no version=2.64 X-Spam-Checker-Version: SpamAssassin 2.64 (2004-01-11) on us.svf.stuba.sk Resent-From: md@bts.sk Resent-Date: Mon, 24 Jan 2005 19:03:56 +0100 Resent-To: freebsd-net@freebsd.org Subject: Re: Making ICMP the default traceroute protocol? 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: Mon, 24 Jan 2005 18:04:07 -0000 > I disagree. Firstly, IWFs tend to also block ICMP. Secondly, routers > sometimes queue ICMP differently than UDP (not just in their own > processing, which they almost always do, but also in their forwarding), > giving even more distortion to these data than they naturally possess > otherwise. Well, that's true, however, the backward packets of traceroute probes are ICMP "ttl exceeded" anyway... The main motivation I'm proposing this is significantly less support for UDP traceroutes that ICMP traceroutes. Several important www sites have dropped UDP traceroute support (try e.g. www.cisco.com, www.google.com, www.dtag.de or many many others). Also on intranet level, WinXP boxes with SP2 installed have no support for UDP traceroutes either. > If you are finding that your destinations tend to need ICMP, I'd > recommend aliasing traceroute to "traceroute -I". Of course I have "traceroute -P icmp" in my alias list for some time, which fixes the problem for me, however I just think it's better to have it as default and use UDP/TCP just for experienced users which exactly know what they're doing... With kind regards, M. -------------------------------------------------------------------------- ---- ---- ---- Marian Durkovic network manager ---- ---- ---- ---- Slovak Technical University Tel: +421 2 524 51 301 ---- ---- Computer Centre, Nam. Slobody 17 Fax: +421 2 524 94 351 ---- ---- 812 43 Bratislava, Slovak Republic E-mail/sip: md@bts.sk ---- ---- ---- --------------------------------------------------------------------------