For reasons of extra security or because you want to exclude a PC from the wifi network connection in your home or office, it is absolutely possible to block any wifi device from accessing the network if it is not authorized. The trick is to configure a router security system that allows access to only a few well-specified devices via an identification address called the Mac Address . The Mac Address is the unique number that is assigned to each network card inserted in a computer, a smartphone and also on a TV or anything that can be connected to a router, both in wifi and cable. The Mac Address is written with 12 characters interspersed with a dash in this way 00-50-FC-A0-67-2C and can usually be found written on a label on the device or via software through applications or programs.
Therefore, if you tell the router to connect only devices with a certain mac address to the network and, therefore, also to the internet, or if you want to exclude some devices, you must use the Mac Address filter function.
This option is present in all routers and is really simple to configure.
You just need to enter the router's control panel, usually by opening a browser tab at 192.168.1.1 and entering your login name and password.
If no custom credentials have ever been set, the login and password are usually admin admin.
If not, see here how to know the login password of each router.
After logging in, find the Wireless Mac Filtering or Mac Address Filter function (you can find it in the wireless settings or in the advanced settings or in the security settings), select the mode, whether to allow network access only to some devices or allow it to all but a few, and add the addresses to the list.
To find out the Mac Addresses of the PCs or mobile phones connected to the network, you can always find the list of connected devices in the router settings or, more easily, use a program / app for PC, Mac, for iPhone and for Android.
The best app is Fing, already mentioned in the article on how to check if someone steals the wifi internet connection, able to list all the devices connected on the network with their IP address, name and Mac Address. Once the unrecognized Mac Addresses have been identified, you can write them in the Mac Filtering blacklist on the router or, once you have identified the Mac Addresses of the PCs and mobile phones you want to connect to the network excluding all the others, add them to the list of allowed ones excluding all others. In this way, no one from outside and no guest will be able to connect to the internet on our network.
On all routers, instead of the standard Mac Address filter, you can also find the Parental Control option to set specific times when a device, always identified with its Mac Address, can connect to the internet.
Mac filtering is a different thing than Mac Binding, another router option that can be found in various settings.
Mac Binding allows you to reserve a specific IP address to a device by associating a local IP such as 192.168.1.23 with the Mac Address.
This option is not intended to block computers or telephones from accessing the network, but only to set fixed IP addresses locally to the various connected computers.
Yet another option that you can use to limit the internet connections of some devices is that of Bandwidth Control or Bandwidth Control . With this option, you can make sure that devices that have a certain IP address have limits in internet downloads and in the usable bandwidth. This configuration can be useful for slowing down the download speed of guests in the home or office from the Internet.
In any case, remember to change the router's name and password to prevent someone else from using these options for themselves.
