Comment 25 for bug 458290

I installed Ubuntu Karmic a few days back, and used Network Manager to connect to a hidden WPA-TKIP wireless network. There were two problems.

1. Network Manager did not connect to the hidden wireless network (no SSID broadcast) by default. When doing this manually, the dialog had "Connect" button disabled. Installing a PPA version of the network manager solved this issue.

2. Connection to the wireless network dropped and reconnected frequently. After some cases of disconnect, subsequent reconnection attempts failed and required a reboot to establish network connectivity. The same issue persisted with wicd and network manager.

Solution:
Removed both network-manager and wicd
Configured wireless network in /etc/network/interfaces and /etc/wpa-supplicant.conf
Installed gnome-netstatus to show network status of wlan0 on the panel (to replace network manager)

Wireless connection has not dropped since. This is better than the network-manager solution because network is available before logging in, and even without starting X.

[Complete file contents for /etc/network/interfaces and /etc/wpa_supplicant.conf are given below]

/etc/network/interfaces
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auto lo
iface lo inet loopback

auto wlan0
iface wlan0 inet dhcp
        pre-up wpa_supplicant -Dwext -iwlan0 -c/etc/wpa_supplicant.conf -B
        post-down killall -q wpa_supplicant
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/etc/wpa-supplicant.conf
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network={
        ssid="my_ssid"
        psk=generated_psk
}
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