Chapter 4. How To Configure SIP
Routing
If the SIP server is located on a NATed network, all SIP traffic from the outside will be directed to the Telecommuting Module, which must know where to forward it.
One way to do this is to enter the SIP domain in the DNS Override For SIP Requests table on the Routing page, to link the SIP server IP address to the name. The Telecommuting Module will look up the domain here instead of in the DNS server, and send the SIP traffic to the correct IP address.
Interoperability
You need to set the URI Encoding settings on the Interoperability page to "Use shorter, encrypted URIs".
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