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Click 
Apply
to save the settings.
The page shown in the following figure appears. A 
virtual server is added. 
4.3.3 
Port Triggering 
Some applications require that specific ports in the firewall of the device are open 
for remote parties to gain access. Application rules dynamically open the firewall 
ports when an application on the LAN initiates a TCP/UDP connection to a remote 
party using the trigger ports. The device allows the remote party from the WAN side 
to establish new connections back to the application on the LAN side using the 
firewall ports. A maximum of 32 entries can be configured. 
Choose 
ADVANCED
> 
Port Triggering
. The page shown in the following figure 
appears. 
 
                 
                                
                    
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Click 
Add
to add a new Port Trigger. 
 
                 
                                
                    
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Click the 
Select an application 
drop-down menu to choose the application you 
want to setup for port triggering. When you have chosen an application the default 
Trigger settings will populate the table below. 
If the application you want to setup isn’t listed, click the 
Custom application 
radio 
button and type in a name for the trigger in the Custom application field. Configure 
the 
Trigger Port Start
, 
Trigger Port End
, 
Trigger Protocol
, 
Open Port Start
, 
Open Port End 
and 
Open Protocol 
settings for the port trigger you want to 
configure. 
When you have finished click the 
Apply 
button. 
4.3.4 
DMZ 
Since some applications are not compatible with NAT, the device supports the use 
of a DMZ IP address for a single host on the LAN. This IP address is not protected 
by NAT and it is visible to agents on the Internet with the correct type of software. 
 
                 
                                
                    
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Note that any client PC in the DMZ is exposed to various types of security risks. If 
you use the DMZ, take measures (such as client-based virus protection) to protect 
the remaining client PCs on your LAN from possible contamination through DMZ. 
Choose 
ADVANCED
> 
DMZ
. The page shown in the following figure appears. 
Click 
Apply
to save the settings. 
4.3.5 
Parental Control 
Choose 
ADVANCED
> 
Parental Control
. The 
Parent Control
page shown in the 
following figure appears. 
This page provides two useful tools for restricting Internet access. 
Block Websites
allows you to quickly create a list of all websites that you wish to stop users from 
accessing. 
Block MAC Address 
allows you to control when clients or PCs 
connected to the device are allowed to access the Internet. 
 
                 
                                
                    
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4.3.5.1 
Block Website 
In the
Parent Control
page, click 
Block Website
. The page shown in the following 
figure appears. 
Click 
Add
. The page shown in the following page appears. 
Enter the website in the 
URL
field. Select the 
Schedule
from the drop-down list, or 
select 
Manual Schedule
and select the corresponding time and days. 
Click 
Apply
to add the website to the 
BLOCK WEBSITE 
table. The page shown in 
the following figure appears.