Port Triggering - TP-Link TL-WR642G User Manual

4.7.2 Port Triggering

Some applications require multiple connections, like Internet games, video conferencing, Internet
calling and so on. These applications cannot work with a pure NAT router. Port Triggering is
used for some of these applications that can work with an NAT router. You can set up Port
Triggering on this page shown in Figure 4-27:
Once configured, operation is as follows:
1. A local host makes an outgoing connection using a destination port number defined in the
Trigger Port field.
2. The router records this connection, opens the incoming port or ports associated with this
entry in the Port Triggering table, and associates them with the local host.
3. When necessary the external host will be able to connect to the local host using one of the
ports defined in the Incoming Ports field.
Trigger Port - The port for outgoing traffic. An outgoing connection using this port will
"Trigger" this rule.
Trigger Protocol - The protocol used for Trigger Ports, either TCP, UDP, or All (all
protocols supported by the router).
Incoming Ports Range - The port or port range used by the remote system when it
responds to the outgoing request. A response using one of these ports will be forwarded to
the PC that triggered this rule. You can input at most 5 groups of ports (or port section).
Every group of ports must be set apart with ",". For example, 2000-2038, 2050-2051, 2085,
3010-3030.
Incoming Protocol - The protocol used for Incoming Ports Range, either TCP or UDP, or
ALL (all protocols supported by the router).
Status - The status of this entry either Enabled or Disabled.
To add a new rule, enter the following data on the Port Triggering screen.
1. Click the Add New button.(pop-up Figure 4-27)
2. Enter a port number used by the application when it generates an outgoing request.
3. Select the protocol used for Trigger Port from the pull-down list, either TCP, UDP, or All.
4. Enter the range of port numbers used by the remote system when it responds to the PC's
TL-WR642G 108M Wireless Router User Guide
Figure 4-27 Port Triggering
40