PAI Field Modification with LUA Script

[Emmanuel Akum]

We have a CUCM SIP Trunk connected to a 3rd Party Automatic Call Distributor System (ACD). Some of the numbers of the Agents on the ACD are PSTN numbers and there are issues with calls coming in from the PSTN to the ACD, which are then forwarded back to the PSTN numbers of the Agents as the ACD is not sending an appropriate number in the PAI field in the invites. I'm looking for a simple LUA script, with which I can insert a particular number in the PAI field for all calls coming from the ACD. Any suggestions?

[Alex Stevenson]

Hi @Emmanuel Akum,

Almost all the Lua Scripts I have seen are for SIP Normalization:

Lua Scripting

1. Configure SIP Normalization Script in CCM - Configuration Examples and TechNotes
https://www.cisco.com/c/en/us/support/docs/unified-communications/unified-communications-manager-callmanager/213516-configure-sip-normalization-script-in-cc.html

2. A guide to SIP Normalization on CUCM and Lua Scripting - Examples given (please note this discussion is several pages long)
https://community.cisco.com/t5/collaboration-voice-and-video/a-guide-to-sip-normalization-on-cucm-and-lua-scripting/ba-p/3099409

3. CUCM-Lua - An External GitHub repo with 5 Lua script examples
https://github.com/gj0nyg/CUCM-Lua

These may not be exactly what you need but may provide a starting point.

I also found this blog, which may be helpful:

Using LUA Script to Allow SIP-Based Phones to Dial from the CUCM Corporate Directory

https://goziro.com/using-lua-script-to-allow-sip-based-phones-to-dial-from-the-cucm-corporate-directory/

I hope this helps!