Sitecom N600 X5 User Manual page 43

DMZ
If you have a client PC that cannot run an Internet application (e.g. Games)
properly from behind the NAT firewall, then you can open up the firewall
restrictions to unrestricted two-way Internet access by defining a DMZ Host.
The DMZ function allows you to re-direct all packets going to your WAN port
IP address to a particular IP address in your LAN. The difference between the
virtual server and the DMZ function is that the virtual server re-directs a
particular service/Internet application (e.g. FTP, websites) to a particular LAN
client/server, whereas DMZ re-directs all packets (regardless of services)
going to your WAN IP address to a particular LAN client/server.
Enable DMZ Enable/disable DMZ
Public IP Address The IP address of the WAN port or any other Public IP
addresses given to you by your ISP
Client PC IP Address Fill-in the IP address of a particular host in your LAN
that will receive all the packets originally going to the WAN port/Public IP
address above.
Click <Apply> at the bottom of the screen to save the above configurations.