From owner-freebsd-net@FreeBSD.ORG Fri May 19 19:11:37 2006 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 09BEE16A46B for ; Fri, 19 May 2006 19:11:37 +0000 (UTC) (envelope-from julian@elischer.org) Received: from a50.ironport.com (a50.ironport.com [63.251.108.112]) by mx1.FreeBSD.org (Postfix) with ESMTP id B7B4B43D4C for ; Fri, 19 May 2006 19:11:36 +0000 (GMT) (envelope-from julian@elischer.org) Received: from unknown (HELO [10.251.23.205]) ([10.251.23.205]) by a50.ironport.com with ESMTP; 19 May 2006 12:11:36 -0700 Message-ID: <446E1868.8020704@elischer.org> Date: Fri, 19 May 2006 12:11:36 -0700 From: Julian Elischer User-Agent: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.7.13) Gecko/20060414 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Ian Smith References: In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-net@freebsd.org, Mike Tancsa Subject: Re: improving transport over lossy links ? 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, 19 May 2006 19:11:38 -0000 Ian Smith wrote: >On Fri, 19 May 2006 at 11:06:48 -0400, Mike Tancsa wrote: > > > I am looking for a way to improve the reliability of a lossy link > > (dialup from remote sites). I am going to try multilink PPP but was > > wondering if something like ng_one2many might work as well ? Does > > anyone have any suggestions for avenues to explore ? For multilink > > ppp, does mpd offer any better performance / reliability over the stock ppp ? > >No idea whether these options may help, but .. > > mpd does well, bit keep the mtu on the interface relatively small if you have a lot of line noise. I have not tried ppp with multilink. > > > The application is low bandwidth, but doesnt deal that well with > > packet loss and the phone lines in these remote locations tend to be > > noisy and drop connections frequently. > >If by 'drop connections' you mean physical loss of line / carrier, then >tuning the modem/s to be (preferably much) less aggressive about forcing >the modem connection rate high - ie being easily satisfied to drop back >to lower rates during hard times - has helped a lot with a dozen or so >remote spots hereaboots. Finding the knobs for some modems can be hard. > >Assuming that V.42 error correction is working properly - forced if need >be - there shouldn't =be= any data loss, however slow getting through, >this side of protocol timeouts of course. I can't guess your mystery >application, but often slower connections are better than dropped ones, >or even ones that spend half their time trying to retrain at high rates. > >cheers, Ian > >_______________________________________________ >freebsd-net@freebsd.org mailing list >http://lists.freebsd.org/mailman/listinfo/freebsd-net >To unsubscribe, send any mail to "freebsd-net-unsubscribe@freebsd.org" > >