User`s guide

Networks
Polycom, Inc. 2–23
2 Configure these settings on the Firewall screen:
Setting Description
Fixed Ports Lets you specify whether to define the TCP and UDP ports.
• If the firewall is not H.323 compatible, enable this
setting. The Polycom HDX system assigns a range of
ports starting with the TCP and UDP ports you specify.
The system defaults to a range beginning with port 3230
for both TCP and UDP.
Note: You must open the corresponding ports in the
firewall. You must also open the firewall’s TCP port
1720 to allow H.323 traffic.
• If the firewall is H.323 compatible or the system is not
behind a firewall, disable this setting.
For IP you need 2 TCP ports per connection, 8 UDP ports
per connection. For SIP you need TCP port 5060, 8 UDP
ports per connection.
Note: With the introduction of ICE support to HDX systems,
the range of fixed UDP ports increased from 56 to 112. The
HDX system cycles through the available ports from call to
call. After the system restarts, the first call begins with the
first port number, either 49152 or 3230. Subsequent calls
start with the last port used, for example, the first call uses
ports 3230 to 3236, the second call uses ports 3236 to
3242, the third call uses ports 3242 through 3248, and so
on.
TCP Ports
UDP Ports
Lets you specify the beginning value for the range of TCP
and UDP ports used by the system. The system
automatically sets the range of ports based on the
beginning value you set.
Note: You must also open the firewall’s TCP port 1720 to
allow H.323 traffic.
Enable H.460
Firewall Traversal
Allows the system to use H.460-based firewall traversal for
IP calls. For more information, refer to H.460 Firewall/NAT
Traversal on page 2-24.
NAT Configuration Lets you specify whether the system should determine the
NAT Public WAN Address automatically.
• If the system is not behind a NAT or is connected to the
IP network through a Virtual Private Network (VPN),
select Off.
• If the system is behind a NAT that allows HTTP traffic,
select Auto.
• If the system is behind a NAT that does not allow HTTP
traffic, select Manual.
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.