Specify Internet Port Settings
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AC1750 WiFi Cable Modem Router
2. Your modem router receives the message and finds your port forwarding rule for incoming
port 80 traffic.
3. The modem router changes the destination in the message to IP address 192.168.0.123
and sends the message to that computer.
4. Your web server at IP address 192.168.0.123 receives the request and sends a reply
message to your
modem router.
5. Your modem router performs Network
Address Translation (NAT) on the source IP address,
and sends the reply through the Internet to the computer or wireless device that sent the
web page request.
Set Up Port Triggering
Port triggering is a dynamic extension of port forwarding that is useful in these cases:
• An application uses port forwarding to more than one local computer (but not
simultaneously).
• An application opens incoming ports that are different from the outgoing port.
With port triggering, the modem router monitors traf
fic to the Internet from an outbound
“trigger” port that you specify. For outbound traf
fic from that port, the modem router saves the
IP address of the computer that sent the traffic. The modem router temporarily opens the
incoming port or ports that you specify in your rule, and forwards that incoming traffic to that
destination.
Port forwarding creates a static mapping of a port number or range of ports to a single local
computer
. Port triggering can dynamically open ports to any computer when needed and
close the ports when they are no longer needed.
Note: If you enabled port triggering because you use applications such as
multiplayer gaming, peer-to-peer connections, real-time
communications such as instant messaging, or remote assistance (a
feature in Windows XP), enable Universal Plug and Play (UPnP). See
Improve Network Connections with Universal Plug and Play on
page 63.
Add a Port Triggering Service
To add a port triggering service:
1. Launch a web browser from a computer or wireless device that is connected to the
network.
2. T
ype http://routerlogin.net or http://192.168.0.1
.
A login screen displays.
3. Enter the modem router user name and password.