Polycom Webcam - Manual (Page 188)

ViewStation EX User Guide
186 www.polycom.com
Downspeeding or Resynchronizing with RadVision via IP
Gateway
Your system has the ability to downspeed and resynchronize
correctly in an H.320 call with a RadVision system and vice versa.
The two systems resynchronize the call if an ISDN line is lost during
the call, if H.320 framing is lost, or if CRC errors are encountered
continuously. The call also downspeeds in the event of a
lower-speed, incoming call or when necessary to add another
outbound call to create a multipoint conference.
Multipoint Calls and Firewall Information
The following information specifies how many TCP and UDP ports
need to be opened through a firewall for multipoint calls.
The port assignment is defined in the Firewall & LAN Connection
screen, under Use Fixed Ports.
To define ports:
1. Access the Firewall & LAN Connection screen by selecting
System
Info > Admin Setup > LAN/H.323 > LAN/Intranet >
Firewall/LAN Connection .
2. Select the option Use Fixed Ports.
3. Assign the correct number of fixed ports for your multipoint
call. To obtain this information, refer to the table below.
Table 6-3. Firewall TCP/UDP Ports in Multipoint Calls
Placing Multipoint Video Calls
There are several ways to place multipoint video calls:
Number of Sites in
Call
TCP Ports UDP Ports
2 3230-3231 3230-3235
3 3230-3233 3230-3241
4 3230-3235 3230-3247