In addition to specifying the port number used, you also need to specify the protocol used.
The protocol is determined by the particular application. Most applications use TCP or UDP,
however you can specify other protocols using the drop-down
Protocol
menu. Setting the
protocol to “all” causes 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 are checked by the Firewall and
NAT algorithms, then passed to the DMZ host when a packet received does not use a port
number in use by any other Virtual Server entries.
Using port forwarding does have security implications, since outside users
are 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 creating a Virtual
Server entry for “All” protocols, as doing so results in all connection
attempts to your public IP address accessing the specified PC.
If you disable the NAT option in the WAN-ISP section, the Virtual Server
function becomes 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 a
static IP address to each virtual server PC, with an address that does not
fall into the range of IP addresses that are 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
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