Administrator's Guide

Chapter 5. How To Configure Advanced SIP
The same matching definitions can be made with regular expressions. Here, each number
range only needs one definition, as the "?" sign marks that the previous character can appear
0 or 1 times. The part of the number that we want to forward should be within parantheses.
In the Forward To table, you define where calls should be forwarded. This is used in the
Dial Plan table below.
In this case, define your two PBXs, simply by entering their respective IP addresses in the
Replacement URI field.
The same forwarding definitions can be made with regular expressions. The "$1" expression
collects the number that matched the expression inside the parantheses in the Matching
Request-URI table.
At last, you combine these definitions in the Dial Plan table.
Select the operator, range, and then select to which PBX to send this call.
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