Currently we have FreePBX setup to add the PAI header in SIP. This is enabled by adding the following to the outbound settings of the trunk
When doing the wireshark (TCPDUMP) trace it is currently inserting the CID of the extension (number) into the PAI header as well which is fine normally
However for regulatory reasons we need to force a number in the PAI header which may be different to that of the extension for that one trunk.
Some extensions DONT have a CID (well their CID is ‘Withheld’), however for legal reasons we need to still send the office number in the PAI header so it can be tracked back to us or if that extension dials emergency services.
Our end result in the headers of a PCAP/WIRESHARK dump needs to be: