ALG (Application Layer Gateway): You can select to enable, then the router will let that application correctly pass though the NAT gateway.
DMZ (Demilitarized Zone)
If you have a client PC that cannot run Internet application properly from behind the NAT firewall or after configuring the Special Applications function, then you can open the client up to unrestricted
Enter the IP address of a DMZ host to this screen. Adding a client to the DMZ (Demilitarized Zone) may expose your local network to a variety of security risks, so only use this option as a last resort.
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