TANDBERG 1000 MXP User Manual page 185

TANDBERG 1000 MXP
H.323 Ports
When selecting static H.323 ports for TCP connections the ports 5555 to 5574
Static
will be used for Q.931 and H.245 respectively.
The system will allocate which ports to use when opening a TCP connection.
Dynamic
The reason for doing this is to avoid using the same ports for subsequent calls
as some firewall consider this as a sign of attack.
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