ViewStation EX, ViewStation FX Administrator's Guide VS4000

Chapter 3 - Configuring Network Use
© Polycom, Inc. 3-7
Configuring the System for Use with a Firewall or NAT
A firewall protects an organization’s network by controlling data traffic from
outside the network. Unless your firewall is designed to work with H.323
videoconferencing equipment, you must configure the system and the firewall to
allow videoconferencing traffic to pass in and out of the network.
Network Address Translation (NAT) network environments use private internal IP
addresses for devices within the network, while using one external IP address to
allow devices on the LAN to communicate with other devices outside the LAN. If
your system uses a NAT, it must be assigned a public IP address to communicate
outside the LAN.
To set up the system to work with a firewall or NAT:
1. Go to System Info > Admin Setup > LAN/H.323 > LAN/Intranet >
Firewall/LAN Connection.
2. Configure these settings:
Setting Description
Use Fixed Ports Lets you specify whether to define the TCP and UDP ports.
This enables the ViewStation system to assign a range of ports
starting with the TCP and UDP ports you specify. In most cases,
the range begins with port 3230 for both TCP and UDP.
Note: You must also open the firewall’s TCP port 1720 to allow
H.323 traffic.
TCP Ports
UDP Ports
Lets you specify the beginning value for the range of TCP and
UDP Ports used by the system.
Note: You must also open the firewall’s TCP port 1720 to allow
H.323 traffic.
System is Behind a
NAT
Lets you specify that the system obtains its IP address from the
NAT. If users connect to this system using a Virtual Private
Network (VPN), clear this field.
NAT is H.323
Compatible
Lets you specify that the system is behind a NAT that allows
HTTP traffic.
Auto Discover NAT Lets you specify whether the system should determine the NAT
Public Address automatically.
The system restarts if you change this setting.
NAT Public (WAN)
Address
Displays the address that callers from outside the LAN use to call
your system. If you chose to configure the NAT manually, enter
the NAT Public Address here.
The system restarts if you change this setting.
Address Displayed in
Global Address Book
Lets you choose whether to display this system’s public or private
address in the Global Address Book.