P.RG F4202N
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HBK 939800036-A1
Security Section
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 the Router's 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.
FIGURE 5.
Port Triggering panel
WEB SITE RESTRICTIONS
You may configure the Router to block specific Internet web sites so that they
cannot be accessed from computers in the home network. Moreover, restric-
