From owner-freebsd-net@FreeBSD.ORG Wed Jun 15 19:04:24 2005 Return-Path: X-Original-To: freebsd-net@freebsd.org 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 5EE6216A41C; Wed, 15 Jun 2005 19:04:24 +0000 (GMT) (envelope-from PeterJeremy@optushome.com.au) Received: from mail11.syd.optusnet.com.au (mail11.syd.optusnet.com.au [211.29.132.192]) by mx1.FreeBSD.org (Postfix) with ESMTP id DF0BF43D49; Wed, 15 Jun 2005 19:04:23 +0000 (GMT) (envelope-from PeterJeremy@optushome.com.au) Received: from cirb503493.alcatel.com.au (c220-239-8-51.belrs4.nsw.optusnet.com.au [220.239.8.51]) by mail11.syd.optusnet.com.au (8.12.11/8.12.11) with ESMTP id j5FJ4Kr0010819 (version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=NO); Thu, 16 Jun 2005 05:04:21 +1000 Received: from cirb503493.alcatel.com.au (localhost.alcatel.com.au [127.0.0.1]) by cirb503493.alcatel.com.au (8.12.10/8.12.10) with ESMTP id j5FJ4KRx056418; Thu, 16 Jun 2005 05:04:20 +1000 (EST) (envelope-from pjeremy@cirb503493.alcatel.com.au) Received: (from pjeremy@localhost) by cirb503493.alcatel.com.au (8.12.10/8.12.9/Submit) id j5FJ4Jl3056417; Thu, 16 Jun 2005 05:04:19 +1000 (EST) (envelope-from pjeremy) Date: Thu, 16 Jun 2005 05:04:19 +1000 From: Peter Jeremy To: "M.Jessa" Message-ID: <20050615190418.GD50157@cirb503493.alcatel.com.au> References: <58397.148.122.180.9.1118829978.squirrel@mail.yazzy.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <58397.148.122.180.9.1118829978.squirrel@mail.yazzy.org> User-Agent: Mutt/1.4.2i Cc: freebsd-net@freebsd.org, current@freebsd.org Subject: Re: Looking for networking solution. 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: Wed, 15 Jun 2005 19:04:24 -0000 On Wed, 2005-Jun-15 12:06:18 +0200, M.Jessa wrote: >I am looking for solution I could implement on a link with a huge latency >when ping replies can go up to a few hundred miliseconds, e.g sateliete >links. What is the problem you are trying to solve? Satellite links have a fairly constant round-trip delay and the RTT calculations built into TCP will happily compensate for this. As long as the TCP window size is larger than the delay*bandwidth and the packet loss probability is well below 1 packet per window, TCP should work fine. >What I was thinking about is some kind of virtual interface which could >translate tcp to udp in one of the pears of the link and push the data it >received from a 'normal' interface through the virtual interface without >bothering about ack-timing. How does the transmitter confirm that the receiver has received packets and can therefore drop them from its transmit buffer (or resend them if they are not received)? In particular, if there is no traffic for a period, the only way that the last packet (before the break) can be confirmed is via acknowledge timeouts. -- Peter Jeremy