How The Router Implements The Port Forwarding Rule; Port Triggering - NETGEAR Nighthawk X8 5 User Manual

To make a local web server public:
1. Assign your web server either a fixed IP address or a dynamic IP address using DHCP address reservation.
In this example, your router always gives your web server an IP address of 192.168.1.33.
2. On the Port Forwarding/Port Triggering page, configure the router to forward the HTTP service to the local
address of your web server at 192.168.1.33.
HTTP (port 80) is the standard protocol for web servers.
3. (Optional) Register a host name with a Dynamic DNS service and specify that name in the Dynamic DNS page
of the router.
Dynamic DNS makes it much easier to access a server from the Internet because you can type the name in the
Internet browser. Otherwise, you must know the IP address that the ISP assigned, which typically changes.

How the Router Implements the Port Forwarding Rule

The following sequence shows the effects of a port forwarding rule:
1. When you type the URL www.example.com in your browser, the browser sends a web page request message
with the following destination information:
• Destination address. The IP address of www.example.com, which is the address of your router.
• Destination port number. 80, which is the standard port number for a web server process.
2. Your router receives the message and finds your port forwarding rule for incoming port 80 traffic.
3. The router changes the destination in the message to IP address 192.168.1.123 and sends the message to that
computer.
4. Your web server at IP address 192.168.1.123 receives the request and sends a reply message to your router.
5. Your router performs Network Address Translation (NAT) on the source IP address and sends the reply through
the Internet to the computer or WiFi device that sent the web page request.

Port Triggering

Port triggering is a dynamic extension of port forwarding that is useful in these cases:
• An application must use port forwarding to more than one local computer (but not simultaneously).
• An application must open incoming ports that are different from the outgoing port.
With port triggering, the router monitors traffic to the Internet from an outbound "trigger" port that you specify. For
outbound traffic from that port, the router saves the IP address of the computer that sent the traffic. The router
temporarily opens the incoming port or ports that you specify in your rule and forwards that incoming traffic to that
destination.
Nighthawk X8 AC5300 Tri-Band WiFi Router
Customize Internet Traffic Rules for Ports
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