Port Forwarding And Port Triggering; Remote Computer Access Basics - NETGEAR CG3700EMR-1CMNDS User Manual

This screen displays a list of currently active wireless computers and devices and their
Ethernet MAC addresses.
5. If the wireless computer or device you want displays in the list, select its radio button to
capture its MAC address. Otherwise, type its MAC address.
The MAC address is found on the computer or device.
6. If no device name displays, type a descriptive name for the computer or device that you are
adding.
7. Click the Add button.
The Wireless Card Access List screen displays.
8. Click the Apply button.

Port Forwarding and Port Triggering

By default, the gateway blocks inbound traffic from the Internet to your computers except for
replies to your outbound traffic. Create exceptions to this rule for these purposes:
• To allow remote computers on the Internet to access a server on your local network.
• To allow certain applications and games to work correctly when your gateway does not
recognize their replies.
Your gateway provides two features for creating these exceptions: port forwarding and port
triggering. The next sections provide background information to help you understand how
port forwarding and port triggering work, and the differences between the two.

Remote Computer Access Basics

When a computer on your network accesses a computer on the Internet, your computer
sends your gateway a message containing the source and destination address and process
information. Before forwarding your message to the remote computer, your gateway must
modify the source information and create and track the communication session so that
replies can be routed back to your computer.
Here is an example of normal outbound traffic and the resulting inbound responses:
1. You open a browser, and your operating system assigns port number 5678 to this
browser session.
2. You type http://www.example.com into the URL field, and your computer creates a web page
request message with the following address and port information. The request message is
sent to your gateway:
• Source address. The IP address of your computer.
• Source port number. 5678, which is the browser session.
• Destination address. The IP address of www.example.com, which your computer
finds by asking a DNS server.
Wireless Cable Voice Gateway CG3700EMR-1CMNDS
Advanced Settings
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