Wireless Network Watcher is a small, completely portable program (there's no installation required -- just double-click the file to start it) that displays a list of all the devices connected to your network. The program scans the network constantly as long as it is running, so you can use it to watch people and devices log on and off in real time.
You might have to do a little sleuthing to make sense of the program's display. You'll see your router, all the wireless laptops in your organization, as well as smartphones and tablets that are connecting via Wi-Fi. And then there are wireless printers and network drives. If you're on a home office network, you might also see entries for TIVOs or Sonos boxes -- you might be surprised at the large number of gadgets that latch onto your network wirelessly. But if you see devices you simply can't account for, then you might have a hacker.
Wireless Network Watcher is a handy little tool for seeing who and what is using your wireless network. If you manage that network yourself, or you're concerned about security, give it a shot.
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