PLANET ADN-4000 - Manual (Page 52)

3.5.3.1 Virtual Server
Go to Advanced Setup ->NAT -> Virtual Server to set virtual server as you need.
(known as Port Mapping).
Use the Virtual Server function when you want different servers/clients in your LAN to
handle different service/Internet application type (e.g. Email, FTP, Web server etc.)
from the Internet. Computers use numbers called port numbers to recognize a particular
service/Internet application type. The Virtual Server allows you to re-direct a particular
service port number (from the Internet/WAN) to a particular LAN private IP Address
and its service port number.
The Virtual Server is the server or server(s) behind NAT (on the LAN), for example,
Web server or FTP server, that you can make visible to the outside world even though
NAT makes your whole inside network appear as a single machine to the outside world.
The following table describes the labels in this screen.
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