Once Wi-Fi defense is installed it scans your network and presents to you a list of devices (computers) and ask you if they are Friend, Foe, or Unknown. It gives you their IP address, MAC address, Net Name, and manufacturer. From that information you can figure out if they are Friend or Foe to allow them on the network. If Unknown you certainly don t want them. If someone need tries to piggy-back onto your signal a pop-up window will alert you and ask you if they are Friend, Foe, or Unknown. It worked on both my 802.11g and b cards. If you find in the future you want to change the classification of visitor (you were mistaken, or they just ticked you off) you can edit the visitor or delete them from the list. Clicking on Wireless Security gives you options for Notification, that will have it tell you when someone new is scanned on the network. The Security tab lets you enable router security. Wi-Fi Defense is truly just a scanning programwhich will tell you when someone is accessing your network, until you enable the router security. I change my setting for my main computerWi-Fi defense options menu from friend to foe. It only change the color setting but, did not kick it off. If you are using a wireless access point in conjunction with a router (two separate pieces of equipment), make sure you put the address of your access point into the Access Point Address field on the Network tab. Once security is enabled if you need to add new visitors (friends) then you can click on Add Friend To Network wizard.