Wifi
From Attie's Wiki
NetworkManager tends to get in the way... big time. Don't forget to kill him.
WEP
stop network-manager ifconfig wlan0 down iwconfig wlan0 essid my_network iwconfig wlan0 key s:my_passphrase iwconfig wlan0 mode managed ifconfig wlan0 up dhclient -v wlan0
Alternatively you can specify the hex value for the key:
iwconfig wlan0 key ...
WPA2
This is untested, but something like this might work:
stop network-manager ifconfig wlan0 down iwconfig wlan0 essid my_network wpa_passphrase my_network my_passphrase > wpa_supp.conf killall wpa_supplicant wpa_supplicant -B -Dwext -iwlan0 -cwpa_supp.conf dhclient wlan0