Subject: Re: Atheros tweaks
To: NetBSD-net <tech-net@NetBSD.org>
From: David Young <dyoung@pobox.com>
List: tech-net
Date: 03/08/2006 12:09:55
On Wed, Mar 08, 2006 at 05:41:39PM +0000, Marcin Jessa wrote:
> Hi guys.
> 
> I created an image with NetBSD which will run on WRAP boards
> for a buddy who runs an ISP. The WRAP boards are small embedded devices 
> (www.pcengines.ch) and will act as wireless clients.
> He wants to connect to access points over longer distances - more than 10 miles.
> I think he uses StarOS now or RouterOS for the same purpose.
> The system works pretty damn well in my lab but the distance is of course pretty short here.
> My question is how to adjust atheros to work flawlesly on long range links? 
> What sysctl values would need to be tweaked ?
> I am using NetBSD 3.99.16 and ath HAL version is 0.9.16.13

There are sysctls for the purpose of changing the timeouts for
long-distance links, hw.ath0.acktimeout and hw.ath0.ctstimeout.  Units are
microseconds; defaults (at least for 802.11b) are 48us.

See John Atkinson's report on using ath(4) to make wireless links over
several kilometers in rural Ghana,
<http://lists.chambana.net/mailman/archive/cu-wireless-dev/2006-January/001021.html>.
John is using CUWiN's NetBSD-based software for ad hoc wireless networks.
CUWiN runs on Soekris & WRAP boards.  I hope to have it running on cheap
APs based on the Atheros SoC in a few months.

Dave

-- 
David Young             OJC Technologies
dyoung@ojctech.com      Urbana, IL * (217) 278-3933