User`s guide

MBR L13 – User’s Guide
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Figure 47: DMZ Host
2. Enter the local IP address of the computer that you would like to designate as a DMZ host and select the
check box. Note that only one LAN computer may be a DMZ host at any time.
3. Click OK to save the settings.
You can disable the DMZ host so that it will not be fully exposed to the Internet, but keep its IP address recorded on
the DMZ Host screen. This may be useful if you wish to disable the DMZ host but expect that you will want to enable it
again in the future.
 To disable the DMZ host so that it will not be fully exposed to the Internet:
Clear the check box next to the DMZ IP designation, and click OK. To reinstate it at a later time, simply reselect the
check box.
3.7.1.6 Port Triggering
Port triggering can be used for dynamic port forwarding configuration. By setting port triggering rules, you can allow
inbound traffic to arrive at a specific LAN host using ports different than those used for the outbound traffic. This is
called port triggering since the outbound traffic triggers to which ports inbound traffic is directed.
For example, consider a gaming server that is accessed using UDP protocol on port 2222. The gaming server responds
by connecting the user using UDP on port 3333 when starting gaming sessions. In such a case you must use port
triggering, since this scenario conflicts with the following default firewall settings:
 The firewall blocks inbound traffic by default.
 The server replies to L13 IP, and the connection is not sent back to your host, since it is not part of a session.
In order to solve this you need to define a Port Triggering entry, which allows inbound traffic on UDP port 3333 only
after a LAN host generated traffic to UDP port 2222. This will result in accepting the inbound traffic from the gaming
server and sending it back to the LAN Host which originated the outgoing traffic to UDP port 2222. Select the 'Port
Triggering tab in the Security management screen. The Port Triggering screen will appear (see Figure 48: Port
Triggering). This screen will list all of the port triggering entries.
Figure 48: Port Triggering
 To add an entry for the gaming example above:
1. Select the User Defined option in the Protocol column to add an entry. The Edit Port Triggering Rule screen
will appear.