When you use the Virtual Server, Port Forwarding, or Remote Administration features to open specific ports to traffic from the Internet, you could be increasing the exposure of your LAN to cyberattacks from the Internet.
In these cases, you can use Inbound Filters to limit that exposure by specifying the IP addresses of internet hosts that you trust to access your LAN through the ports that you have opened. You might, for example, only allow access to a game server on your home LAN from the computers of friends whom you have invited to play the games on that server.
Inbound Filters can be used for limiting access to a server on your network to a system or group of systems. Filter rules can be used with Virtual Server, Gaming, or Remote Administration features. Each filter can be used for several functions; for example a "Game Clan" filter might allow all of the members of a particular gaming group to play several different games for which gaming entries have been created. At the same time, an "Admin" filter might only allow systems from your office network to access the WAN admin pages and an FTP server you use at home. If you add an IP address to a filter, the change is effected in all of the places where the filter is used.
Please launch your browser and enter http://dlinkrouter.local or http://192.168.0.1 into the address bar. Then login and follow the steps below:
Step 1: Click on Features on the top and then Firewall
Step 2: Click on IPV4 Rules, then select Turn IPV4 Filtering ON and ALLOW rules listed, then click Add Rule
Step 3: Create your rule
Step 4: Click Save after adding your rule.
Note: If you’d like to block specific IP addresses accessing your router, please select “Turn IPV4 Filtering ON and ALLOW rules listed” from the drop-down menu.