Q:What is Netstumbler?
-NetStumbler is a tool for Windows that allows you to detect Wireless Local Area Networks (WLANs) using 802.11b, 802.11a and 802.11g. It has many uses:
-Verify that your network is set up the way you intended.
-Find locations with poor coverage in your WLAN.
-Detect other networks that may be causing interference on your network.
-Detect unauthorized "rogue" access points in your workplace.
-Help aim directional antennas for long-haul WLAN links.
-Use it recreationally for WarDriving.
Q:Where do I download Netstumbler?
You can download Netstumbler here.
Q:When I open Netstumbler, it tells me my wireless card improperly configured!?
This simply means you have your current wireless configuration only connecting on a specific SSID. You need to change your wireless profile to look for the SSID "ANY", so it will pick up all networks.
Q:When I try to scan for networks, it says "Access Denied" at the bottom of the screen. How do I fix that?
Most likely, this is happening because you are not on a Windows account with sufficient privileges. When you run Netstumbler it will try and change some info in your wireless config and some non-administrative accounts are not allowed to do this.
Q:Netstumbler tells me "No Wireless Adapter Found", even though I'm using my wireless card to read this post right now! What's going on?
Your wireless card may not be supported by Netstumbler. On the Netstumbler forums, they have this thread that talks about working wireless cards along with this thread that talks about cards that don't work and have problems. If your wireless card shows up in both lists, then it's more of a hit and miss thing. Your card may work, and may not.
Q:What if my card is listed in the "Not working" thread and I can't get Netstumbler to recognize it? How can I fix that?
Try searching the Netstumbler forums for your specific wireless card model to see if anyone else has been able to get it to work. If nobody has gotten it to work, then you may want to get another wireless card, if you really want Netstumbler to work.
Q:I'm running Netstumbler and the "Signal" is -100 for every network. How's that possible?
If your card is running in NDIS mode in Netstumbler, the signal will always be reported as -100. You can check if you're running in NDIS mode by going to "Device" along the Netstumbler menu.
Q:I found an AP that I know is running WPA but Netstumbler is reporting it as WEP. Is my network really only running WEP?
Most likely, no. Netstumbler will report WPA/WEP networks all as WEP. The program makes no difference in reporting. In older versions of Netstumbler, WPA wouldn't even show up as encrypted and my guess would be, in the later versions, there will be a difference in how Netstumbler reports the network encryption.
Q:If a network has "MAC Filtering" will Netstumbler show it as secure?
No. Netstumbler only shows networks running WEP/WPA as secure.
Q:I ran Netstumbler and I'm only picking up my own network and nobody else, but I know there are other networks. Is something wrong?
Yes. Most likely you need to change your wireless config to search for SSID "ANY" instead of your SSID. You can change this in your wireless configuration utility in Windows.
Q:Is there a program like Netstumbler that runs under Linux?
Yes. The most common program is Kismet.
Q:Will Netstumbler allow me to connect to networks I find?
No. Netstumbler will only detect networks, not connect to them.
Q:While I'm scanning for networks, I see a * next to the channel number of the network. What does this mean?
This means either you have connected, or are connected, to the network.
Q:After I've scanned my neighborhood for networks, how do I create fancy statistics pages?
You can do this with many scripts that are available online, especially in the "Netstumbler Forums". Google has many other programs/scripts that will do the same thing.
Q:I drove through my neighborhood and I found less than 10 APs. Is this right?
Maybe. Either the residents of your neighborhood haven't decided to get wireless APs or your wireless card isn't powerful enough to detect the networks. If you are sure there are networks available, look into getting a new, higher-powered, wireless card with an external antenna connector.
Q:So what wireless cards work the best with Netstumbler?
Most people prefer the Orinoco and SMC wireless cards. Both have external antenna connectors and are compatible with Netstumbler.
Q:I had Netstumbler running while I was going through ____________ (Insert random place here) and I detected a wireless network. There wasn't even any houses around! How's that possible?
Many long range trucking companies have started to put wireless communicators inside the trucks to track the drivers. The most famous "random" network is "SST-PR1", which belongs to Sears.
Q:While scanning with Netstumbler, some networks vendors show up as "Fake" or "User-defined". What is this?
The "Fake" vendor is usually the all 0 MAC address. Most likely, your wireless card had a hiccup. Just unplug your wireless card, and plug it back in. That should fix the problem. "User-defined" vendor means the MAC address on that AP isn't in the Netstumbler database because it doesn't match a known vendor.
Q:Is Netstumbler a free program?
Yes, it is completely free to use. If you want, you can donate money here to help the development of Netstumbler, but it isn't required.
Q:What if my question wasn't answered here? Where can I get extra help?
You can check out the Netstumbler forums.
Feedback received on this FAQ entry: