19216811.live(Wireless) ADSL VPN Firewall Router with 3DES Accelerator
Chapter 4: Configuration
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In addition to specifying the port number to be used, you will also need to specify the protocol
used. The protocol used is determined by the particular application. Most applications will use
TCP or UDP, however you can specify other protocols using the drop-down
Protocol
menu.
Setting the protocol to “all” will cause all incoming connection attempts using all protocols on all
port numbers to be forwarded to the specified IP address.
DMZ:
The DMZ Host is a local computer exposed to the Internet. When setting a particular
internal IP address as the DMZ Host, all incoming packets will be checked by the Firewall and
NAT algorithms, then passed to the DMZ host when a packet received does not use a port
number used by any other Virtual Server entries.
If you have disabled the NAT option in the WAN-ISP section, the Virtual Server
function will hence be invalid.
Attention
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 easiest way of
configuring Virtual Servers is to manually assign static IP address to each virtual
server PC, with an address that does not fall into the range of IP addresses that
are to be issued by the DHCP server. You can configure the virtual server IP
address manually, but it must still be in the same subnet as the router.
Attention
Using port forwarding does have security implications, as outside users will
be able to connect to PCs on your network. For this reason you are
advised to use specific Virtual Server entries just for the ports your
application requires instead of simply using DMZ or create a Virtual Server
entry for “All” protocols, as doing so will result in all connection attempts to
your public IP address will access the PC specified.