User's Manual
103
Virtual Server
Virtual Server allows you to direct incoming trafc from WAN side (identied by Protocol and
External port) to the Internal server with private IP address on the LAN side. The Internal port is
required only if the external port needs to be converted to a different port number used by the
server on the LAN side.
The device can be congured as a virtual server so that remote users accessing services such
as Web or FTP services via the public (WAN) IP address can be automatically redirected to local
servers in the LAN network. Depending on the requested service (TCP/UDP port number), the
device redirects the external service request to the appropriate server within the LAN network.
In TCP and UDP networks a port is a 16-bit number used to identify which application program
(usually a server) incoming connections should be delivered to. Some ports have numbers that
are pre-assigned to them by the IANA (the Internet Assigned Numbers Authority), and these are
referred to as “well-known ports”. Servers follow the well-known port assignments so clients can
locate them.
If you wish to run a server on your network that can be accessed from the WAN (i.e. from other
machines on the Internet that are outside your local network), or any application that can accept
incoming connections (e.g. Peer-to-peer/P2P software such as instant messaging applications and
P2P le-sharing applications) and are using NAT (Network Address Translation), then you need to
congure your router to forward these incoming connection attempts using specic ports to the PC
on your network running the application. You also need to use port forwarding if you wish to host
an online game server.