Trying to put PS4 into dmz

[kidkubi]

When I go to enter the IP address of the PS4 to enable dmz for it my modem tells me that the IP address invalid. I know it's the right IP address assigned to the PS4. What can I do to make this work? My isp was having trouble opening ports so I need to resort to dmz.

 

[failboat]

Just lookup the ports that need to be forwarded and use port forwarding.
Under DHCP leases do a fixed one by MAC address on the PS4.
upnp, "dmz hosts" or any other type of software that opens all inbound connections is very insecure.