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Discovering Wireless LANs
Figure 9-1:
Finding
the MAC
address of
an AP by
using arp.
Chapter 9: Wireless LANs
After you have a wireless card and wireless testing software, you’re ready to
roll. The first tests you should perform gather information about your WLAN,
as described in the following sections.
Checking for worldwide recognition
The first test requires only the MAC address of your AP and access to the
Internet. (You can find out more about MAC addresses later in this chapter,
in the “Mac spoofing” section.) You’re testing to see whether someone has
discovered your WLAN and posted information about it for the world to see.
Here’s how the test works:
1. Find your AP’s MAC address.
If you’re not sure what your AP’s MAC address is, you should be able to
view it by using the arp -a command at a Windows command prompt.
You might have to ping the access point’s IP address first so the MAC
address is loaded into your ARP cache. Figure 9-1 shows what this can
look like.
2. After you have the AP’s MAC address, browse to the WiGLE database
of WLANs (www.wigle.net).
3. Register with the site so you can perform a database query. It’s worth it.
4. Select the Query link and log in.
You see a screen similar to Figure 9-2.
5. To see whether your AP is listed, you can enter such AP information
as geographical coordinates, but the simplest thing to do is enter your
MAC address in the format shown in the example for the BSSID or
MAC text box.
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