Cisco 9951 and 9971 tftp provisioning over internet in freepbx

[chris001]

A couple of questions about Provisioner with Cisco 9971 9951 and Freepbx 12 (Incredible pbx) Asterisk 13.

1. Upgrade procedure. Can you just git clone or git pull this code and overlay the open source Provisioner that comes with Freepbx? Or is there some procedure to get it to fit into Freepbx Incredible PBX.
2. Any known issues with Cisco 9951 9971 ? Seen several issues open with the cisco 79xx which is loosely similar.
3. Securing the TFTP server. The configuration files on there contain extension numbers and passwords. For example, say a 9951 or 9971 is out on the internet. Is anyone else limiting access to the TFTP server running on the Freepbx Incredible server. Are you using knock, IP, or just using VLAN, which is not exactly automatic or self-starting.