Remote Extensions
From Taridium
This optional ipbx module is installed under Advanced Setup → Modules. Registered modules are displayed with registered module.
Remote Extensions are extensions that are not local, meaning not connected directly to the PBX. This module is intended for use with legacy PBX interconnections via T1/E1 card. It allows you to specify users to use a trunk as 'device' thus exposing all ipbx features to a traditional telephone system.