The feature you describe is mostly referred to as "Beacons". The way I understand it is, the AP sends out beacons to announce its presence... this allows cards such as Lucent, to be set in SSID "ANY" mode so it will grab the nearest it can find. Turning off beacons on the AP, is commonly referred to "CLosed Wireless System" or something similar. I turn off beacons on all my AP's, to prevent guys like me from finding them. :-) I also tried discovering useful info from my AP's while beaconing is off... and failed. It appears that my card won't pass packets to the laptop unless it feels that it is associated with an AP... and without my SSID it sits in "duh, I'm searching and/or out of range" mode... Perhaps someone knows how to make the thing pass all radio packets it receives even without even being associated with an AP...