From owner-freebsd-stable@FreeBSD.ORG Thu Mar 9 04:09:15 2006 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2C69C16A420 for ; Thu, 9 Mar 2006 04:09:15 +0000 (GMT) (envelope-from sam@errno.com) Received: from ebb.errno.com (ebb.errno.com [69.12.149.25]) by mx1.FreeBSD.org (Postfix) with ESMTP id CFD4543D45 for ; Thu, 9 Mar 2006 04:09:14 +0000 (GMT) (envelope-from sam@errno.com) Received: from [10.0.0.199] ([10.0.0.199]) (authenticated bits=0) by ebb.errno.com (8.12.9/8.12.6) with ESMTP id k2949Ao7065026 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 8 Mar 2006 20:09:13 -0800 (PST) (envelope-from sam@errno.com) Message-ID: <440FAA67.7020708@errno.com> Date: Wed, 08 Mar 2006 20:09:11 -0800 From: Sam Leffler Organization: Errno Consulting User-Agent: Thunderbird 1.5 (Macintosh/20051201) MIME-Version: 1.0 To: "Daniel O'Connor" References: <20060308231529.GA2049@afflictions.org> <20060308235940.GA64762@intserv.int1.b.intern> <200603082111.37010.joao@matik.com.br> <200603091105.38164.doconnor@gsoft.com.au> In-Reply-To: <200603091105.38164.doconnor@gsoft.com.au> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-stable@freebsd.org, JoaoBR Subject: Re: ath(4) and 802.11g speed X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 09 Mar 2006 04:09:15 -0000 Daniel O'Connor wrote: > On Thursday 09 March 2006 10:41, JoaoBR wrote: >>> It looks like "man ath" does not list all media and mediaopt values. >> sure not because there are lots of different cards out with different >> mediaopts so you need to read your hw-manual or your card can answer >> ifconfig -m ath0 > > In any case I imagine there is no point forcing it to use 54Mbit - it will > negotiate the highest speed it can manage based on signal strength and > hardware support (for the AP and the card) automatically. > > I suspect forcing 54Mbit will either not work at all (because the signal isn't > strong enough or your hardware doesn't support it), or it will negotiate a > speed up to 54Mbit (which would result in no functional change). > Locking the transmit rate (and that's what setting the media does) can be useful but rarely when operating in any configuration but a p2p setup where the endpoints are fixed. The algorithm used to select a transmit rate for a frame is very important to getting good performance. John Bickett's sample algorithm, typically used with ath, is pretty good but could still be improved. Sam