Advanced Features
Virtual Servers
This feature, sometimes called Port Forwarding, 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.
Figure 37: 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.
Virtual Servers Screen
∙The "Virtual Servers" feature allows Internet Users to access PCs on your LAN.
∙The PCs must be running the appropriate Server Software.
∙For Internet Users, ALL of your Servers have the same IP address. This IP ad- dress is allocated by your ISP.
∙To make it easier for Internet users to connect to your Servers, you can use the "DDNS" feature. This allows Internet users to connect to your Servers with a URL, rather than an IP address. This technology works even if your ISP allocates dy- namic IP addresses (IP address is allocated upon connection, so it may change each time you connect).
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