Telephone intercom system - PABX switching system

This video talks about the Telephone intercom system PBX switch which is the "engine of the PBX system.
The video describes the pbx switch.
The characteristics of the pbx switch - it is a programmable device.
They are programmed using a PC or a key telephone.
The telephone intercom system switch capacities available and how to describe the capacities.
A description of Extension ports.
A description of CO Line ports.
A description of door phone ports.
Music on hold source description.
Office phone systems.
phone systems.
business phone systems.
phone system for small business
pbx equipment.
pbx device.
pbx solutions.
what is pbx?
key phone system.
Telephone intercom systems.
how telephone systems work
telephone intercom switch