Why should you secure your Wi-Fi?Stealing someone's Internet is called piggybacking and may cause you following issues:-
- Multiple users may reduce your Internet speed; they can easily use your connection for downloading large data.
- If you are using pay as use Internet plan or limited data plan, they can increase your Internet bill.
- Hackers can easily get access to your computer and files and also abuse your connection for doing illegal stuff so you have to face law suites by copyright owners incase of illegal downloading including may other law enforceable issues.
Secure A Wireless Network
- Open your Router's setting page ( It is printed on back of your router, read: - Find your router's IP for more help)
- Change Default Name and Password of your Router.
- Set a password for Wireless network as well: - Navigate to Wireless section and choose security type and enter a unique password.(Prefer using WPA2 and disable WPS option)
- Use Mac address filtering if you are in a home network and only allow your devices through Mac address filtering.
Once you have all needful things to secure your Wi-Fi, forget and connect all your devices to new Wi-Fi network if renamed with new passwords but if you are using mac filtering just delete the previous Wi-Fi setting from your devices and connect it again usually. It will not ask you for any password because your Wi-Fi will be open to added mac addresses. This method is less secure, but you can use mac address filtering with a password to ultimately secure your Wi-Fi network.
If you still have doubt do check who is connected to your Wi-Fi from router's setting page > Wi-Fi connection status or use a few good tools to find out connected devices.