D-Link Express Ethernetwork DI-604 Owner's Manual page 18

ADVANCED > VIRTUAL SERVER
The firewall filters out unrecognized packets to protect your LAN (local area network);
so all computers networked with the DI-604 are invisible to the outside world. If you
wish, you can make some of them accessible by enabling the Virtual Server
Mapping.
A virtual server is defined as a Service Port, and all requests to this port will be
redirected to the computer specified by the Server IP.
For example, if you have an FTP server (port 21) at 192.168.0.1, a Web server (port
80) at 192.168.0.2, and a VPN server at 192.168.0.6, then you need to specify the
following virtual server-mapping table:
Service Port
21
80
1723
Server IP
192.168.0.1
192.168.0.2
192.168.0.6
18
Enable
V
V
V