I hope I'm at the right place with my question. Already tried it in the Zyxel forum but they're not as active as you guys are. So I'm here.
I want that devices inside a specific IP range can not access or communicate with the internet. They shall just communicate locally. To achieve this I went to the firewall settings of my Zyxel router and found the option to create ACL rules. I think that's the solution but I don't know how to configure it.
Here you can see the options I have:
Would an ACL rule be the solution to my problem? And how should I configure this? Already tried a few things but it seems like that I can only permit the connection between local devices and not local device to wan.