XP "deauthenticate" after 802.1x authentication finished

Jouni Malinen jkmaline
Sun Aug 1 17:14:03 PDT 2004

On Fri, Jul 30, 2004 at 03:28:04PM -0700, yuannong at emobilenetworks.com wrote:

>  Hostap driver 0.2.4, Linux2.4, and WindowsXP as a client. The problem comes when I
>  turn on i802.1x authentication by using freeradius. The authentication method
> is PEAP
>  and this problem seems have nothing to do with authentication method directly.

What card and with what driver version are you using in the client?

>  In fact everything works pretty well. The i802.1x authentication works fine,
> but several seconds after the i802.1x authentication finishs, XP always sends
> out a "deauthentication" frame with reason code 3:(Station has left the basic
> service area..)

Exactly how many seconds is "several seconds"? Five?

It looks like you have configured hostapd not to use dynamic WEP keys
(wep_key_len_broadcast and wep_key_len_unicast are not set to non-zero
values). Is the client configured with "keys are generated
automatically" (or something similar, I don't remember the exact

Even if the client is configured correctly, WinXP (at least SP1) does
not really like unencrypted IEEE 802.1X connections, so I would highly
recommend testing this with dynamic WEP keying enabled. If this does not
help, you might be able to get more information from the EAPOL tracing
log of the Microsoft supplicant.

> (3)restart "hostapd". The whole process will start again almost same as first run of
> "hostapd" except it seems no waiting mentioned in (2). And guess what? This XP
> "deauthentication" problem disappears!!!

I remember hearing of (and also seeing myself) odd behavior from the
WinXP supplicant, so I'm not too surprised of this. Setting the WEP keys
through IEEE 802.1X could help for this.

Jouni Malinen                                            PGP id EFC895FA

More information about the Hostap mailing list