Polycom DOC2230A - Manual (Page 70)

MGC-50/MGC-100 Getting Started Guide
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d. (Optional) Define the following fields.
Table 3-17: Fixed Ports & NAT Options
Field Description
Enable Fixed Ports
Enable Fixed Ports Select this check box to enable the configuration of
firewall ports used for signaling, control and media. If
you are defining a service for local calls that do not
require configuring the firewall to accept calls from
external entities, leave this check box clear.
Number of calls Enter the Number of Calls based on the predicted
number of simultaneous incoming calls that require
fixed port allocation and are handled by the network
and MCU, up to the maximum that can be handled
by the IP card (dependent on card type).
If you exceed the maximum number of calls
configured for the card an error message appears
listing the call range that can be entered.
Port Range
Definitions The following general instructions apply to the
Signaling, Control, Audio, Video, data and FECC
fields.
Define the port ranges for each of the channels;
enter the first port for each channel and the system
automatically fills in the end of the assigned port
range. The IANA recommended port range is 49152
to 65535.
The network administrator configures the server and
allocates firewall ports based the number of ports
required for each media channel (13 in total) and the
volume of incoming traffic via the firewall (the
number of simultaneous calls).
For example: If each call is allocated 13 ports
(Signaling - 1, Control - 1, Audio - 2, Video - 4, and
Data - 5, for a total of 13 ports), and 6 simultaneous
calls are to be handled by the network, the total
number of ports that is required is 78 (6 x 13). If the
first allocated port is 1025, then the last port will be
2003 (1025 + 78 = 2003).