Problem with "Captive Portal" of Siemens HiPath WLAN Controller

[Erik Auerswald <auerswald fg-networking de>]

Hi,

I have encountered a problem with one implementation method of a guest
access WLAN using Siemens HiPath WLAN controllers using a captive portal
and an open WLAN.

The basic idea of this method is to change VLANs on the controller side:
A new client connects to the AP and first is placed in a restricted VLAN with
access to the controller's captive portal only. After entering username and
password in the portal page, the controller places the client in a
different VLAN (using different IP addresses) and sends a "deauthenticated"
message to the client. The client then reconnects (that part is working),
but it keeps its old IP address (which does not work any more). A new DHCP
request is needed to receive a valid IP address for the guest VLAN.

The logs show that the WLAN is disconnected and then reconnected, but the
IP address is not renewed:

Dec  6 17:55:19 fgn-t61 NetworkManager: <info>  (wlan0): supplicant connection state:  completed -> disconnected
Dec  6 17:55:19 fgn-t61 NetworkManager: <info>  (wlan0): supplicant connection state:  disconnected -> scanning
Dec  6 17:55:21 fgn-t61 NetworkManager: <info>  (wlan0): supplicant connection state:  scanning -> associating
Dec  6 17:55:21 fgn-t61 NetworkManager: <info>  (wlan0): supplicant connection state:  associating -> associated
Dec  6 17:55:21 fgn-t61 NetworkManager: <info>  (wlan0): supplicant connection state:  associated -> completed

SSID and MAC address of the AP stay the same, there is just the
deauthentication to signal a change. The WLAN is open (no encryption).

This is working correctly with Windows XP, Windows Mobile and iPhones...

I am using NetworkManager 0.8 from Ubuntu 10.04.1.

Please CC: me on replies as I am not subscribed.

Thanks
Erik
-- 
Dipl.-Inform. Erik Auerswald                http://www.fg-networking.de/
auerswald fg-networking de Tel: +49-631-4149988-0 Fax: +49-631-4149988-9

Gesellschaft für Fundamental Generic Networking mbH
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