Internet Features
Virtual Servers
This feature allows you to make Servers on your LAN accessible to Internet users. Normally, Internet users would not be able to access a server on your LAN because:
∙Your Server does not have a valid external IP Address.
∙Attempts to connect to devices on your LAN are blocked by the firewall in this device.
The "Virtual Server" feature solves these problems and allows Internet users to connect to your servers, as illustrated below.
Figure33: Virtual Servers
IP Address seen by Internet Users
Note that, in this illustration, both Internet users are connecting to the same IP Address, but using different protocols.
To Internet users, all virtual Servers on your LAN have the same IP Address. This IP Address is allocated by your ISP.
This address should be static, rather than dynamic, to make it easier for Internet users to connect to your Servers.
However, you can use the DDNS (Dynamic DNS) feature to allow users to connect to your Virtual Servers using a URL, instead of an IP Address.
Using the DMZ port for Virtual Servers
You should connect your Virtual Servers to the DMZ port, for the following reasons:
∙Traffic passing between the DMZ and LAN passes through the firewall. The firewall will protect your LAN if your Server is compromised and used to launch an attack on your LAN.
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