I have found problems with various wifi setups and the following, on BOTH windows and linux
DHCPclient does not work, have to set fixed IP-this is because not all APs pass DHCP requests.
WEP stops connection working
WPA stops connection working (just because WPA is available, doesn't mean the hardware supports it)
Enabling WPA stops network detection working.
ESSID or SSID is case sensitive.(oops)
speed negotiation does not work, or defaults to 11Mbit
Encryption slows network to a crawl if using more than one client card, or using different speed cards
There are many other issues, as a whole WIFI is not a mature technology, there are many vendors selling kit with varying degrees of compatability and compliance.
The same can be said of Bluetooth and USB.
I personally use MAC filtering on my home network, I think that that is probably sufficient in my environment.
My signal just reaches the bottom of the garden at home, at work, we use WEP, but within a steel clad building, they would need to press a laptop to one of the windows (sic) to connect,
As a general rule, buy all of your kit from the same manufacturer at the same time, and it should all work, but it may not, and there is no guarantee that 802.11 b will work with 802.11g or 802.11n for example.
I use wifi on my laptop at home with Suse 10.1, and at work with XP. trying to get multiple profiles on either is a nightmare, often just fails.
I need to connect to various wired and wifi networks, (sometimes 4 or more a day) and I just configure manually as required.
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