Subject: Re: Experimental EAP support for Aironet
To: Atsushi Onoe <>
From: Wolfgang Rupprecht <>
List: tech-net
Date: 07/02/2001 11:51:38
> Hmm.  I have one of the access point and if any of you have ACS RADIUS
> server and are kind enough to make a test account which I can access from
> my access point as NAS, it would be very helpful.

I only have a 4-year old Ascend-modified (but otherwise vanilla)
Radius server here.  I guess the problem is that this ACS stuff is a
cisco-proprietary extension.

> First you should tell which mode you want to use: infrastructure mode
> or IBSS (adhoc) mode.  If you want to connect via access point, you
> should be infrastructure mode, I guess it is most of the case.
> In infrastructure mode, the station (NIC) tries to synchronize the
> radio channel which is used by the access point which it wants to make
> association.  Before establishment of association, the card continues
> to scan and try a next access point, so that it doesn't stick to one
> channel.

I was trying to change the channel while in IBSS mode, by loading a
new value into:

      (struct an_ltv_genconfig *) cfg->an_ds_channel = newchannel;

The Cisco user literature didn't mention that the card would scan the
channels all by itself.  I was planning on writing a little shell
script wrapped around ancontrol to scan.  I guess I can save myself
the trouble.

Is there a wildcard SID (eg. "", "ANY" or "any") that will instruct
the card's firmware to take what it can get?

I tried "" but the driver balked that it couldn't initialize the MAC.

> As far as I know about aironet firmware, an_ds_channel parameter of the
> current configuration RID only affects adhoc or access point operation.
> and an_cur_channel parameter of the status RID shows the current channel
> only after it associate an access point (infrastructure mode).  Before
> association, the value is meaningless.
> I can't figure what you did, but if you try to change the value of
> an_cur_channel in AN_RID_STATUS, it fails.  The status register is
> read only as noted in anreg.h.  If you try to change the value of
> an_ds_channel in AN_RID_GENCONFIG, it should affect the IBSS creation
> channel if the card operates in IBSS mode (mediaopt adhoc) and there
> are no IBSS speaker found.  In another words, the default IBSS channel
> is only used there are no wireless station for the SSID, and then
> some station joins the IBSS.

I see.  Yes I was trying to test it by changing channel after an IBSS
association was already formed on channel 6.

Wolfgang Rupprecht    <>
Coming soon: GPS mapping tools for Open Systems.