Advanced Features
51
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.
Broadband
Router
Web Server
FTP Server
Internet
Remote PC
Remote PC
Using Web Server
Using FTP Server
(http://203.70.212.52)
(ftp://203.70.212.52)
203.70.212.52
192.168.0.1
(192.168.0.10)
(192.168.0.20)
(LAN IP Address)
(WAN IP Address)
Figure 31: 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.
