2.5 Virtual Server (Port Forwarding)

If you need to allow outside users access to a computer (or computers) on your LAN—for example, if you are hosting an Internet game—you have to open up an X5’s inbound port. A port is an endpoint to a logical connection. The port number identifies the logical channel being used; for instance, port 21 is associated with FTP (File Transport Protocol). If a port is not opened, the X5 will block and discard the packets.

One way to open up a port is to implement a virtual server (sometimes referred to as port forwarding). Note that one virtual server entry opens up one port. It is possible to open multiple ports (for a maximum of 20), but you have to configure a virtual server entry for each one individually. In other cases, you might want to have all ports open and for this you need to set up a Demilitarized Zone (DMZ); see page 25 for instructions on configuring a DMZ.

An example will help to illustrate how to set up a virtual server. In our example, we will demonstrate how to use your computer as an FTP server.

Tip: We recommend that you visit the ports list section of Practically Networked’s web site if you need help:

http://www.practicallynetworked.com/sharing/app_port_l ist.htm.

1 First you need to specify a Host IP address. Navigate to the LAN Settings page by returning to the Advanced Setup page and clicking LAN. You’ll see the defined starting and ending LAN IP address range; for example, 10.0.0.4 and 10.0.0.15. Your Host IP Address should be a static IP address outside of this range—say, 10.0.0.16.

To set this static IP address, go to Start Settings Network and Dial-up Connections. Right-click Local Area Connection, select Properties, highlight your NIC card’s TCP/IP entry and click Properties.

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X5 ADSL Modem User’s Manual