Auto populate IP address for Pax devices

We recently ran into a POS that was semi integrated with Pax S300 like Linga and they were able to auto populate the IP address of the Pax devices directly from the POS software. This would be a HUGE time savior and would make remote install and support much easier. 

When we asked about if they knew any additional info as to how this was done, they advised that what they do know is that the Pax file has to be build in Paxstore with "POS Auto Register" enabled under Communications.