I have a wired and wireless setup at our home. The wireless is connected to an external antenna. What I'd like to know is why is it when I use Backtrack on Ubuntu I see many more networks than what I do in Windows 7? I also notice that the networks in Windows 7 appear and disappear.
My wireless device is a ALFA awus036h usb 2.0.
How many networks you "see" is primarily a function of the wifi NIC driver. Obviously, Windows and Linux don't use the same driver(s).
In a dense urban environment the number of network signals detected by the hardware is going to be greater than what is presented to the OS and ultimately the user. Some are not going to be reported based on decisions around their apparent availability and signal strength. The cutoff point is determined by driver design.
BackTrack emphasises penetration testing, not reliable connectivity. Hence, the drivers it uses are going to report many more signals than your average Windows driver which is geared towards consumer and business use.
Is there any way around it? Depends on the specific driver you're using. Most likely no. They don't tend to expose their signal strength cutoff points as user-configurable settings, or at least that's my experience. My guess is that most of those values are not hard-wired (the driver will accept input for test and diagnostic purposes), but the challenge would be to find documentation on how that's implemented.
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