Using WEP with the Compaq Wireless Multiport Device (Evo N600c) under Linux

Here are the steps required to get WEP working on the multiport.
Note that you must use at least wlan-ng-0.1.14pre5 to make WEP on USB devices work.
If you are trying to get the multiport device working with authtype=opensystem (i.e. NOT WEP), check out these instructions instead.


Date: Wed, 19 Jun 2002 13:19:35 -0400
From: Josh Wyatt [address deleted]
To: linux-wlan-devel [address deleted], MyeongSu.Lee [address deleted]
Subject: Re: [lwlan-devel] RE: Tja funken.

"Lee, Myeong Su(HOU)" wrote:
> 
> Hello Josh Wyatt,
> 
> I've been attempting to get the wireless 802.11b USB device of the Compaq Evo N600C laptop to work under RedHat 7.2 but couldn't enable it with autotype=sharedkey the shared key.

[snip]
 
> Could you please let me know the step-by-step procedures on how to get the wireless card work?
> 
> Would appreciate your help. Thanks.
> 
> Best Regards,
> --------------------------------------------------------------
> M.S.(Myeong Su), Lee
> PSG - 3rd Level Support Engineering
> Hewlett-Packard Company

Firstly, let me appreciate the irony of HP asking little old me for info
on how to get the multiport device working on the Compaq laptop ;) .

Secondly, I will be glad to help you.

Basically, you must follow these steps:
1. Make sure the prism2_usb module is compiled, installed, and loaded
2. Modify /etc/wlan.conf
3. run /etc/init.d/wlan start
4. configure the new wlan0 interface (with dhcpcd for example)

Sounds like you are OK with #1, and maybe #2, but you didn't do #3, and
instead issued the wlanctl-ng commands from the website.  It works for
opensystem, but some extra MIBs need to be set for shared key
authentication.

Below, I have documented the specific things which need to be changed in
/etc/wlan.conf, and the instructions needed afterwards.  Please let me
know if you have success, and I will post these updated docs on the
site.

To start off, you were correct to try the very latest version of wlan-ng
(which is indeed 0.1.14-pre6 as of this writing).  I know that previous
versions (0.1.13 and prior) have problems with WEP on USB devices.

Assuming you get no errors when you modprobe prism2_usb, you are halfway
there.

The next thing to do is edit /etc/wlan.conf.  To use shared keys, you
should do the following in that file:
1. On or around line 80, change the line that reads:
         dot11PrivacyInvoked=false       # true|false
	to:
         dot11PrivacyInvoked=true        # true|false

2. On or around lines 87-89, comment out the three lines which start
with "PRIV_"

3. On or around line 92, enter your shared key as the value for
dot11WEPDefaultKey0 in hexidecimal digits.  For example:
         dot11WEPDefaultKey0=cb:65:e9:d0:75

(make sure and put *your* shared key in).

Note: a 40-bit key consists of five hexidecimal numbers; a 128-bit key
would consist of thirteen (13) hexidecimal numbers.  The above example
shows a 40-bit key.  I have not yet been able to test 128-bit keys, but
they should work fine.  You can find out your key from your network
administrator.

4. On or around line 102, find the line that says
	AuthType="opensystem"
and change it to:
	AuthType="sharedkey"

5. On or around line 104, change the line that says
	DesiredSSID="linux-wlan"
to:
	DesiredSSID="your_ssid"

6. Double-check your changes, then save the file.

Now, you should be able to do /etc/init.d/wlan start .  Make sure you
get "Success" for the first four set requests.  


Note that if the card is associated with your access point if the green
light will be steady-on, not flashing.  Also, you can make sure you have
the wireless-tools package installed, and then issue:

/sbin/iwconfig wlan0

And it should report the access point you are associated with
(44:44:44:44:44:44 indicates not associated), as well as link quality,
signal level, noise, etc.

After that, you should be able to do 
dhcpcd wlan0

And obtain the address.

If you are not able to associate, but /etc/init.d/wlan start returns the
first four as success, you probably are using the wrong key.

Please let me know how it turns out, and let me know if I can be of
further assistance.

Thanks,
Josh