I use a broadcom airforce one 54g wireless adapter on my hp-compaq nx6125 amd64 notebook, distro is ubuntu-6.06, kernel is 2.6.15.
wlan works fine in my university network which is unsecured, i.e. no wep, wpa whatsoever.

now i'm with my parents for the weekend, they have a small wireless lan with wep-128 running.

saying

>iwlist wlan0 scanning

gives
Cell 01 - Address: [MAC-Address]
ESSID "[network-name]"
Protocol:IEEE 802.11g
Mode:Managed
Frequency:2.412 GHz
Quality: 0/100 Signal level:-64 dBm Noise level:-256 dBm
Encryption key: on
Bit Range: 1Mb/s ... 54 Mb/s
Extra:bcn_int=100
Extra:atim=0

So I try to configure my wlan adapter with

#iwconfig wlan0 essid [network-name]
#
seems to work
I also set the wep-key

#iwconfig wlan0 key s :[13digit ascii key]
#
Ok.

Then another
#iwconfig wlan0

returns

wlan0 IEEE 802.11g ESSID: off/any
Mode:Managed Frequency:2.412 GHz Access-Point:Not associated
Bit-Rate=54 Mb/s Tx-Power 25 dBm
RTS thr: off Fragment thr: off
Encryption key: XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-XX (the correct key) Security-mode:restricted
Power management: off
Link Quality: 0 Signal level: 0 Noise level: 0
Rx invalid nwid: 0 Rx invalid crypt: 0 Rx invalid frag: 0
Tx excessive retries: 0 Invalid misc: 0 Missed beacon: 0


Hm.

Turning off wep on the AP (fritz!-box) does not alter the situation.

Any idea? Is the signal too weak? But iwlist still sees the network.
And my brother can connect from his win* machine.

I also tried to configure the wireless card using
the gui tool (network-admin). It already detects the network, I do all the settings, but then it tries to get an IP-address, at least that's what the console says:

localhost dhclient: DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval ?
...
...
...
localhost dhclient:No DHCPOFFERS received

dhcp is turned on on the AP.

That's all I know for the moment, please let me know if you have any suggestions.

I'm getting a very similar problem.

iwlist returns all the correct info about my network, and the signal strength is 100/100, but the dB is -220 for some reason.

even so, i would expect that if iwlist can find my network, then dhcp should also work.

but when i try dhcpcd eth1 simply times out.

what even more strange is that after that failed attempt, any more iwlist scannings turn up empty.

hii...sorry 2 interfere but i too hav some problem with iwlist scan
using RHEL4-ES,
]# iwlist eth1 scan
eth1 Interface doesn't support scanning : Operation not supported
i'm a newbie in linux..can sum1 help me out?