There are two modes on DMZ function：one is NAT mode，another one is Transparent mode.

In Transparent mode, all interfaces behave as though they are part of the same network, and the firewall filters packets pass through the firewall without modifying any of the source or destination information in the IP packet header. In practical applications，the Company will generally put public servers on DMZ zone.

Step1：menu Configuration->Interface->DMZ

Step2：choose “Transparent”mode，click“Apply”button

Step3：Server behind the DMZ interface with public IP（the IP address with the device’s WAN IP in the same subnet）

Step4：you can access to public server via Internet