There are several ways to find out if someone is stealing your Wi-Fi connection signal. Getting hold of a neighbor’s signal is not as complicated as some people think and is a concern for users who, at some point, the connection starts to go much slower than usual. But this is not the only clue that can hint that they are hacking your wifi. There are several:
Slow connection or intermittent disconnection: a connection that, at certain times of the day, begins to slow down or is lost intermittently without a technical problem in between is one of the main clues to suspect that someone is stealing wifi. Another clue is if the WLAN indicator of the router continues to flash once all connected devices in our home have been disconnected, as indicated by the CNMC.
Unknown computers connected to your signal: less experienced wifi thieves often overlook a detail. That your equipment appears reflected in the list of the owner of the signal on the equipment of your home.
How to find out who uses my wifi
Programs that help you discover who steals your Wi-Fi: discovering who steals your Wi-Fi and configuring your router is a laborious process that can take more time than you have, so there are some programs that try to help you find out if someone is using your signal, as indicated from CNMC:
Desktop computers: Angry IP Scanner and Wireshark, for Windows, Linux, and macOS X.
Specific to Microsoft Windows: Wireless Network Watcher, Microsoft Network Monitor.
Mac-specific: a highlight is Mac OS X Hints.
Specific for Linux.
There are specific programs for Android devices (Fing, Network Discovery, Net Scan).
For iPhone / iPad (Fing, IP Network Scanner, iNet).
Another interesting is Who is on my wifi (Who is on my wifi), which runs in the background and shows who is connected during that time.
These programs help to know who steals your wifi, but only if it is connected at the time of the scan. To know if someone steals our wifi at any time, it is usual to enter the router. How to enter and configure the router
Enter the router and configure it: to enter the router and configure it with Windows, you have to type in the browser the gateway, which is usually 192.168.1.1, although you can find out with the following steps: go to ‘Start’, write ‘ cmd.exe ‘in the search engine (the text box of the magnifying glass), in the window that opens write’ ipconfig ‘and copy in the Internet browser the data that appears in the section’ Default gateway ‘. The user and the password are the ones that came with the serial router. If you have lost or do not know how to access this step, the operator must help the user in any case.
Once inside the router, there is the DHCP section, the ‘log’ section, or the connected equipment register, which shows the addresses of the devices connected to it. Chances are that the IP addresses change, so it is best to use the MAC, something like the signature of the wireless device: Windows, Mac, Android, and iPhone /iPad.
There are also ways to do it for Mac, Linux, iPhone / iPad, and Android.
One of the recommendations is to configure the router so that it only allows access to specific MAC addresses (those of the user).
Why change the wifi password?
Keep in mind that there are many pages that collect wifi connection keys in Reviewimo Best Wifi adapter for gaming, so it is advisable to change it. Changing the name to the Wi-Fi connection is also interesting. From Portal, they point out several reasons why both steps are advisable, apart from what has already been mentioned about key aggregation pages.