How to catch neighbors who steal your Wi-Fi
There are several reasons why your wireless Internet may not be as fast as it was in the past. Your router may need to be patched, for example. Or, the number of devices that connect to it may have increased significantly, because you have bought a new tablet, a modern gaming console, two more smartphones, and so on.
Maybe your neighbors have found out your Wi-Fi password, and now they're downloading huge files and streaming full HD movies using your Internet connection. According to George Hardesty, CEO of Data Alliance, most ISP-supplied devices can't self-update their firmware. Additionally, very few manufacturers release patches, thus making these routers ideal targets for hackers. So, let's see how we can catch them and stop them for good. Yes, that includes you, Bob!
Before we begin, you should know that people who manage to connect to your network will have access to all its shared computing resources. To give you an idea, your evil neigbors may be able to print hundreds of copies of their documents remotely, using your printer. They could also delete your precious photos, videos and may even be able to get access to your credit card info.
The first step is to discover all the devices that are connected to your Wi-Fi network. There are several applications that can do the job; try WifiInfoView if your computer runs Windows Vista, Windows 7, Windows 8, Windows Server 2008, Windows 10, or Wifi Analyzer for mobile phones that use the Android operating system.
The application will create a list with all the devices that are connected to your wireless network; I bet that you'll see a few strange looking network client names as well! Don't worry, though, many of them are devices you've forgotten about; I am talking about old phones, various IoT devices, smartwatches, and so on. To find out if these unknown devices are dangerous, prevent them from accessing your Wi-Fi, and then power on all the wireless gadgets you know of. If everything continues to work fine, you've just kicked the strangers out of your network.
However, if you discover that your signal repeater isn't working anymore, for example, you should use the application's option of renaming devices, and then change that cryptic "N300" name to "D-Link Signal Repeater". This way, you won't disable this necessary Wi-Fi device in the future.
Another idea is to log into your router's admin panel, and then compare the names of the devices that are listed in the "wireless" panel section with the ones that have been displayed by WifiInfoView and/or Wifi Analyzer. You may discover that an unknown device is listed as "Atheros AR9130" in the Wi-Fi client list. Then, by performing a simple Google search, you will find out that this is the name of the CPU that's used for the D-Link DIR-615 rev C1 router.
Once that you've found out the names of all the devices on your Wi-Fi and you have blocked the unknown ones, it's time to increase the security of your wireless network. Begin by upgrading the firmware of your router. Then, replace your router's password; your neighbors may have discovered it as well.
It's time to change the Wi-Fi password; pick one that is long and very hard to guess. Pick a pass that's got at least 12 characters and includes "%", "&", "@" etc. You will have to update the password on all the connected devices, but you won't have to do that again anytime soon.