Administrator's Guide

Chapter 10. SIP Services
SIP Media Port Range
State a port interval which the Telecommuting Module should use for SIP media streams.
You can use any high ports except 4500 (reserved for NAT-T) and 65097-65200 (reserved
for RADIUS).
Note! A change in the port interval will make the SIP module restart when the configuration
change is applied.
When the SIP module is restarted, all active SIP sessions (SIP calls, video conferences etc)
will be torn down and all SIP user registrations will be removed.
Enter the lower and upper limit of the port range that the Telecommuting Module should use
for media streams. The upper limit must be at least as high as the lower limit.
Public IP address for NATed Telecommuting Module
Sometimes, the Telecommuting Module is located behind a NAT box that is not SIP-aware.
This will make signaling go awry, with the result that in many cases there will be voice in
only one direction.
This can be corrected by entering the public IP address that the Telecommuting Module will
appear to have. When sending SIP signaling towards its default gateway, the Telecommuting
Module will use that IP address instead of its private one, which will get media to the right
place.
Note that the NATing device must also be configured to forward SIP signaling on that IP
address to the Telecommuting Module.
If nothing is entered here, the Telecommuting Module will use its own IP addresses.
This setting is not supported for the Standalone configuration.
SIP Servers To Monitor
Your Telecommuting Module can be made to monitor SIP servers, to check that they are
alive. The information is used by the Telecommuting Module when SIP signaling should
be passed on to the server in question. This is useful when a domain resolves to several
individual hosts; the Telecommuting Module will know immediately if one of them is down,
which will speed up the call connection.
The SIP server must respond with a SIP packet to OPTIONS packets to be monitored in this
way.
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