Mac® Security Bible

16.6. Using Wi-Fi Scanning Software

The AirPort menu in your menu bar automatically lists all nearby Wi-Fi networks that broadcast their SSIDs; it even indicates which ones are encrypted by displaying a small padlock icon. In Snow Leopard, you can get additional details about the network to which you're currently connected (including the type of encryption it uses and the current signal strength) by holding down Option while clicking on the menu; for other networks, the information appears in a pop-up tool tip when you hover over the network name.

However, if you're running Leopard, or if you want to gather additional facts about the wireless networks in your vicinity or display the data in a more flexible form, you can use any of several readily available Wi-Fi scanning programs, which are often called stumblers.

Some stumblers exist only to help you gather information. One example is Koingo Software's AirRadar (www.koingosw.com/products/airradar.php, $9.95), shown in Figure 16.17. In addition to the information shown here, you can turn on numerous other columns, displaying information such as the manufacturer of each access point and whether it's an ad hoc network (created by a computer rather than a stand-alone access point). You can also graph the signal of each network over time. A similar program is iStumbler (www.istumbler.net, free). Although iStumbler lacks some of the polish of AirRadar, it offers additional features, such as the capability to monitor not only Wi-Fi ...