different wpa_supplicant drivers

[Dan Williams]

On Tue, 2006-05-23 at 19:51 +0200, Riccardo Veraldi wrote:
> Hello,
> I am trying 802.1x and WPA on different linux distributions always 
> withthe same ipw2200 hardware
> It works but...
> 
> On Red Hat enterprise 4  2.6.9-34.EL using ipw and ieee811 from atrpms
> wpa_supplicant -d -w -ieth1 -Dipw -c /etc/wpa_supplicant.conf

This will change with the next update when the ipw driver is upgraded,
and the RHEL kernel gains WE-18 support.  You will then need to use
'wext'.

> on Fedora Core 5 with kernel 2.6.16-1 I have to use driver wext instead 
> of ipw
> 
> how come ?
> with ipw driver it will not work and wpa_supplicant needs to be started 
> with -Dwext option.
> 
> what I have to do to know in advance if the driver is generic wext or 
> specific ipw2200 ?

You check the driver's version and the kernel Wireless Extensions
version.  Do a 'cat /proc/net/wireless' and you'll see:

[localhost ~]# cat /proc/net/wireless
Inter-| sta-|   Quality        |   Discarded packets               | Missed | WE
 face | tus | link level noise |  nwid  crypt   frag  retry   misc | beacon | 20
  eth0: 0004   93.  191.    0.       0      0      0      3     26        0
[localhost ~]#

My kernel (2.6.17-pre) runs WE-20.

[@localhost ~]# dmesg | grep ipw
ipw2100: Intel(R) PRO/Wireless 2100 Network Driver, git-1.2.2

I have a very recent driver for the ipw2100.

In the end, if you want to know for sure, you need to whip up a small C
program that will check the result of iw_get_range() for your specific
wireless device.  That tells you what WE exact version the driver
supports.  If it supports >= WE-18, it may be able to do WPA.

> Why on Fedora is wext and not ipw ?
> thanks a lot

As was said, it depends on both the driver version and the version of
the Wireless Extensions the kernel you have supports.  Fedora Core 5 is
quite recent, and therefore has kernel support for Wireless Extensions
20 and a very recent ipw2x00 driver.

Previously most drivers implemented their own extensions for WPA, but
now with the push to standardize drivers around Wireless Extensions you
will see more and more drivers move to using 'wext' with wpa_supplicant.
This is a Good Thing.

Dan