Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 10 Jan 2003 20:48:58 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 10 Jan 2003 20:48:58 -0500 Received: from pc2-cwma1-4-cust86.swan.cable.ntl.com ([213.105.254.86]:50835 "EHLO irongate.swansea.linux.org.uk") by vger.kernel.org with ESMTP id ; Fri, 10 Jan 2003 20:48:58 -0500 Subject: Re: How much we can trust packet timestamping From: Alan Cox To: Werner Almesberger Cc: uaca@alumni.uv.es, Linux Kernel Mailing List , dveitch@unimelb.edu.au In-Reply-To: <20030110190706.A6866@almesberger.net> References: <20021230112838.GA928@pusa.informat.uv.es> <1041253743.13097.3.camel@irongate.swansea.linux.org.uk> <20030110190706.A6866@almesberger.net> Content-Type: text/plain Content-Transfer-Encoding: 7bit Organization: Message-Id: <1042253032.32431.28.camel@irongate.swansea.linux.org.uk> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.2.1 (1.2.1-2) Date: 11 Jan 2003 02:43:52 +0000 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 725 Lines: 16 On Fri, 2003-01-10 at 22:07, Werner Almesberger wrote: > One general issue in this area is what we can do with time > sources that aren't system-wide, e.g. NIC-local timers. The > problem is to calibrate them and to synchronize them to > wall-clock time. I think there are basically two possible > approaches: You run NTP between the host clock and the nic timer. Its all you really need. In the i2it hardware the NIC clock implemented hardware slewing so it could do NTP stuff - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/