RE: connecting to a non-broadcasted SSID

["Miner, Jonathan W \(US SSA\)" <jonathan w miner baesystems com>]

Responses at the bottom... apologies for using MS-Outlook...

-----Original Message-----
From:	Dan Williams [mailto:dcbw redhat com]
Sent:	Thu 6/12/2008 11:15 AM
To:	Miner, Jonathan W (US SSA)
Cc:	networkmanager-list gnome org
Subject:	Re: connecting to a non-broadcasted SSID

On Thu, 2008-06-12 at 08:34 -0400, Miner, Jonathan W (US SSA) wrote:
> I've noticed that when I successfully connect to a wireless network with a non-broadcasted SSID that the applet reports:
> 
> "You are now connected to the wireless network '(none)'."
> 
> This message comes from network-manager-applet/src/applet-device-wifi.c, line 1131
> 
> Clearly, NetworkManager knows the SSID of the network, since it was able to look for it, and successfully connect to it.  But it appears that the applet can't determine it?

Depends; the applet _should_ have the right idea of the current AP, but
if you run 'nm-tool' is there a * next to your SSID while connected?  If
not, then the problem lies in NetworkManager.

I did test hidden SSID last week and it worked OK for me, but enough
people have reported this problem that I think there is a bug.

Also, can you report what '/sbin/iwconfig wlan0' (or whatever your wifi
interface name is) says when you're definitely connected?  NM grabs that
information periodically and tries to match it up with an AP that it's
scanned, and if I cannot find the AP that the card says it's associated
too (because it hasn't shown up in scan yet) then you'll end up with
NULL.

So, if you have more than one AP in the same SSID, but none of them are
broadcasting their SSIDs, NM can only auto-match the SSID AP's its seen
before.  So if the card roams to a new AP that NM hasn't seen before,
and also isn't broadcasting it's SSID, that AP won't necessarily be in
the scan list yet, and even if it was, we wouldn't know it's SSID
necessarily.

The solution?  _Don't_ hide your AP's SSID.  It's security through
obscurity, and if you're using good encryption like WPA[2] + 802.1x,
it's completely unnecessary anyway.  Anyone with WireShark can fire up a
frame sniffer and grab your SSID at any time anyway.

Dan

>>>> My responses:

Right now, I only have one AP, but we'll grow to two or three when this gets rolled out. I agree with you on the SSID hiding issue, but that is a political issue.

nm-tool does has an asterisk:

  Wireless Access Points(* = Current AP)
    *FooBar:        Infra, 00:12:17:70:0C:D0, Freq 2437 MHz, Rate 0 Mb/s, Strength 96 WPA Enterprise

iwconfig output:

wlan0     IEEE 802.11  ESSID:"FooBar"  
          Mode:Managed  Frequency:2.437 GHz  Access Point: 00:12:17:70:0C:D0   
          Bit Rate=54 Mb/s   Tx-Power=14 dBm   
          Retry min limit:7   RTS thr:off   Fragment thr=2352 B   
          Encryption key:9A2C-BE5F-2F1C-1595-D71B-8761-0B04-B11E-B396-1F94-B70C-7BB8-2C8A-D5D3-18B8-5073 [2]
          Link Quality=100/100  Signal level:-42 dBm  Noise level=-94 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0