Chapter 3 Configuration
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3.4.6 Virtual Server Being a natural Internet firewall, I-STORM ADSL ROUTER protects your network from being
accessed by outside users. When it needs to allow outside users to access internal servers, e.g. Web
server, FTP server, E-mail server or News server, this product can act as a virtual server. You can set
up a local server with specific port number that stands for the service, e.g. Web (80), FTP (21), Telnet
(23), SMTP (25), POP3 (110), DNS (53), ECHO (7), NNTP (119). When an incoming access request
to the router for specified port is received, it will be forwarded to the corresponding internal server.
For example, if you set the Service Port number 80 (Web) to be mapped to the IP Address
192.168.1.2, then all the http requests from outside users will be forwarded to the local server with IP
address of 192.168.1.2.
DMZ: Regarding the DMZ Host, it is a local computer exposed to the Internet. Therefore, an
incoming packet will be checked by Firewall and NAT algorithms in I-STORM ADSL ROUTER ,
then passed to the DMZ host when packet is not sent by hacker and not limited by virtual server list.
If you have disabled the I-STORM ADSL ROUTER ’s NAT option in the WAN-ISP
section, this Virtual Server function will hence be invalid.
If the DHCP server option is enabled, you have to be very careful in assigning the IP
addresses of the virtual servers in order to avoid conflicts. The easy way is that the IP
address assigned to each virtual server should not fall into the range of IP addresses
that are to be issued by the DHCP server. You configure the virtual server IP address
manually, but it is still in the same subnet with the router.