Typical ports that need to be opened on the firewall:

80 (TCP)
HTTP
Optional for external administration

389 (TCP)
LDAP
ILS registration

1503 (TCP)
T.120

1720 (TCP)
H.323
H.323 call setup

1731 (TCP)
H.323
H.323 audio call control

1024-65535 (UDP)
H.245, RTP, RTCP
Various audio/video controls

As the above list shows, opening the required ports can leave a number of large “holes” in the firewall. Polycom and Tandberg video conference units do give you the option to set a predetermined range instead of opening up the entire range of 1024-65535 (UDP). However, there is one caveat with this: Whatever port range is chosen, it must be set to exactly the same range on both units that are connecting. This can be a challenge especially when both devices are not managed by the same department or organization. Additionally, some devices will not work with the manual configuration of ports (especially if they are from different manufacturers). That being said, the recommended configuration is to open up the full port range (1-65535) for TCP and UDP.

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