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Virtual Server (known as Port Forwarding)
In TCP/IP 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 will
usually need to congure your router to forward these incoming connection attempts using specic
ports to the PC on your network running the application. You will also need to use port forwarding
if you want to host an online game server.
The reason for this is that when using NAT, your publicly accessible IP address will be used by and
point to your router, which then needs to deliver all trafc to the private IP addresses used by your
PCs. Please see the WAN conguration section of this manual for more information on NAT.
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
