Installation
Enabling Network Address Translation (NAT)
Network Address Translation (NAT) enables communication between devices on your LAN that have private IP addresses and devices that are accessed through a public IP network. Static NAT ensures that the same public IP address always maps to a system’s private IP address so that data from the public network intended for the private system can be routed to the system reliably.
If you are using static NAT to associate a public IP address with the private IP address of your system, you must configure your system to work with your static NAT server. Access Administrator Preferences : Network : NAT and select Enabled for the Static NAT preference.
Enter the public IP address, hostname, or fully qualified domain name of your system in NAT Public IP Address. The default
entry method for this preference is numeric. To enter text, use the 
key on the remote control to change the entry method to text.
NOTE
If you are using a static firewall or NAT with fixed ports, you cannot register to a public gatekeeper. If you configure H.323 settings and enable H.460 support, the system ignores preferences in Administrator Preferences : Network : NAT.
Refer to “Enabling H.460 Support for H.323 Calls” on page 43 for more information.
The following functions are not supported if your system is accessed from a web browser outside a firewall and static NAT is enabled:
•System Upgrade
•Directory Import
To work around this issue, execute these functions from within the firewall.
Restricting Reserved Ports
By default, your system communicates through TCP and UDP ports in the range 2 048 to 65 534 for video, voice, presentations, and camera control. The system uses only a small number of these ports during a call. The exact number depends on the number of participants in the call, the protocol used, and the number of ports required for the type (video or voice) of call.
To minimize the number of UDP and TCP ports that are available for communication, you can restrict the range by entering values in Administrator Preferences : Network : Reserved Ports. LG recommends that the range you choose, if other than a subset of the default range, begins with a port number greater than 10 000.
NOTE
Changing the TCP range causes an automatic reboot of the system.
An H.323 video call with a presentation requires more ports than other types of calls.
The following tables identify the number of ports required per connection by protocol and the type (video or voice) of call. Use this information if you need to further restrict the port range.
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Installation
