An advantage of having a WiFi connection is the ability to add multiple devices located anywhere within the WiFi range to connect to internet and between each other. This advantage is also a big problem if the WiFi is intruded by more devices than it is allowed. More devices connected to WiFi leads to reduced quantity and quality of available bandwidth and resources to each device sharing the device.
This is why it is necessary that you periodically check your WiFi connection to find if someone hacked into your WiFi network. Apart from protecting your WiFi from stealing data, it also helps prevent hacking your devices inside the network.
Problems with having unknown resources sharing your WiFi
- WiFi network will slow down than usual
- Increased data usage
- Risk of getting hacked
- Chance of malware attack from an infected computer in the network
How to find unauthorized device in your WiFi network
- Using Router settings:
- Open web browser
- Type 192.168.1.1 or 192.168.0.1 to get into router settings page
- Enter the user name and password
- Check for attached devices
In the picture below there are 5 devices connected to network. Though I am not able to identify each device, the 5 devices listed here makes sense as there are 3 smartphones, a tablet and a computer connected to WiFi. Unfortunately, there are no options to force disconnect if you find any unauthorized device in the list.
- Use network scanning Applications
There are plenty of network scanning applications such as Nmap, Advanced IP Scanner, Wireless Network Watcher, Who Is on My WiFi etc. Some router manufacturers are also releasing Apps like Genie Netgear, Airport Utility, Connect to Linksys etc. These applications are straight forward and give the device name, mac address of devices connected to your WiFi network.
How to prevent unauthorized device penetrating WiFi using Router settings
Every router coming from different models and manufacturers have the same options as mentioned below. These options come with different names. You need to find related option in your Router model.
- The easiest method to prevent WiFi intrusion immediately is to change the password. Once the password is changed, you have to update all legitimate devices with the new password. Unauthorized devices will be automatically thrown out of the WiFi network.
- Change the security encryption to WPA2-PSK (Wi-Fi Protected Access 2 with Pre-Shared Key). Older routers don’t support WPA, instead supports WEP ( Wired Equivalent Privacy). Owners with older routers need to understand WEP is less secure compared to WPA which means it is time to go for a new router.
- If you find any device which is constantly hacking into your WiFi even after changing password and security encryption, you may try to block the device using its Mac address. The option is usually under Wireless Access List. You will have an option to add the Mac address to block list.