Looking Inside the PBX
A PBX consists of hardware and software designed to emulate the public telephone
system within a company, and provide paths into the Public Switched
Telephone Network (PSTN).These systems can be categorized into four primary
areas, with each area containing one or more functions:
Extension termination
Trunk termination
System logic and call processing
Switching
These functions are illustrated in Figure 1.1 and described in greater detail in
the next sections.