Detect network intruders with SoftPerfect Wifi Guard
It’s important to keep your wireless network secure, and turning your encryption levels to the max is usually a very good place to start.
This doesn’t in itself guarantee safety, though, so you may want to also equip your system with SoftPerfect Wifi Guard, which will monitor your network and alert you to devices which it doesn’t recognize.
Initially, of course, this could be quite a few. Just run the program, and while it’s smart enough to recognize a few devices as a part of your network infrastructure (your current PC, your router), everything else will be flagged in its grid as a red "unknown".
This is easily fixed, though: simply right-click a device you recognize, select Properties, check "I know this computer or device" and maybe add something to the Comment box where you say what it is. Then repeat the process until your network is fully documented.
Okay, it’s true, this setup process could take a while if the network is large. But once it’s done, when SoftPerfect Wifi Guard next rescans your network in 30 minutes, it will now display all your regular systems in reassuring green. Only when some new device is uncovered, something which hasn’t been there before, will the program get excited and display an appropriate alert dialog as a warning.
We’ve covered similar programs before. NirSoft’s Wireless Network Watcher, for instance, is also a portable network monitor; its "continuous background scan" is arguably better than Wifi Guard’s "every x minutes" approach; and it has some useful settings, including for instance an option to execute the command of your choice when a new device is detected.
SoftPerfect Wifi Guard is also quite configurable, though: you can choose the network adapter to scan, the IP addresses, the number of devices to scan simultaneously (welcome on large networks) and how often you’d like the program to run its checks.
It’s also lightweight, and extremely easy to use. But perhaps the real plus here is that SoftPerfect Wifi Guard is cross-platform (versions are available for Windows, OS X 10.5 on Intel or higher, and Linux with GTK+ 2.8 or higher), so can monitor your network almost no matter how it’s set up.