Subject: Re: ath driver and wep
To: Sam Leffler <>
From: Steven M. Bellovin <>
List: current-users
Date: 10/01/2005 21:50:43
In message <>, Sam Leffler writes:
>Steven M. Bellovin wrote:
>> In message <>, Vincent writes:
>> =

>>>Greg Troxel a =E9crit :
>>>>I made the following change (locally, not committed) yet to
>>>>sys/dev/ic/ath.c to write wep keys to the hardware on power up.  This=

>>>>intends to fix the problem of wep keys being set while the power is
>>>>off (ifconfig nwkey before ifconfig up), or lost during ifconfig
>>>>down/up.  I tested on one machine and an ifconfig down/up resulted in=

>>>>a working configuration where previously it did not (and I received a=

>>>>report from someone else who had the same problem).
>>>I tested it, not for long, but I was led to this:
>>>It is *definitely* better. but I think it does not solve completely th=
e =

>>>problem, as I found my PC disconnected after a while. And it surely do=
es =

>>>not solve the autodeconnection bug (the card drops the link for some =

>>>unknown reason).
>> =

>> I've frequently had that latter problem, with both a PCMCIA wi0 card =

>> and a built-in ath0, for several years.  It seems to be related to =

>> traffic levels, since I have much more trouble in busy wireless =

>> environments. =

>I'm coming in late on this but regarding ath, if you're seeing frequent =

>beacon misses then I have a workaround for "phantom bmisses" that may be=

>helpful.  It's still being tested; I'll try to pass it along when it's =

>in a form suitable for netbsd (it was developed for freebsd).

I'd be delighted to try it.  I have a trip coming up in about two weeks =

to a place where I've had trouble getting ath0 to work at all of late
(the Amtrak Club Acela in Washington, DC).
>Regarding the wep key and powering the card down; when the interface is =

>marked down the chip should be in full sleep with the radio turned off. =

>  In this state it should draw very little power.  If folks are really =

>seeing power draw in this state then I need more info; especially the =

>part id(s).
That wasn't the issue.  Per the first paragraph above, someone had =

trouble with WEP because of powerdown; someone else suggested not =

powering the card down at all.  Others think that that's a bad idea.

		--Steven M. Bellovin,