Polycom VS4000 User Manual

Page of 150
Integrators’ Reference Manual for ViewStation EX, ViewStation FX, and VS4000
90
www.polycom.com
Configuring the System to Operate Behind a NAT
The System is behind a NAT option allows the user make calls 
outside the internal network. 
At this time, it is not possible to make videoconferencing calls 
within the internal network when the System is behind a NAT 
option is selected. To make videoconferencing calls within the 
network, users must deselect the System is behind a NAT option 
before making the call. 
1.
Determine the NAT’s external (WAN) IP address. 
2.
Determine the IP address of the system. This can be found in the 
System Information
 screen.
3.
Go to Quality of Service and Firewalls screen (System Info > 
Admin Setup > LAN/H.323 > H.323 > QOS
).
4.
Select Use Fixed Ports.
5.
Select System is behind a NAT.
6.
Enter the NAT’s external IP address into the NAT outside 
(WAN) address
 field.
7.
Write down the Fixed TCP and UDP port numbers displayed on 
this screen. The default values are:
TCP: 3230 to 3231
UDP: 3230 to 3235
8.
Reset the firewall’s fixed ports from step 4 to be permanently 
open, and redirect them to the IP address of your system.
9.
To accept incoming calls, open and redirect port 1720 to the IP 
address of your system.