The term PBX spawns from the original term PABX, which is an acronym for Private Automatic Branch Exchange. Essentially a PBX is a private telephony switch that enables a business to operate a phone system with less phone lines than they have employees. This helps organizations take advantage of the natural economies of scale that begin to occur as headcounts rise.

Over time, the PBX has grown to incorporate advanced features such as voicemail, unified messaging, auto attendant (Interactive Voice Response), automatic call distribution (ACD), call queuing, telecommuters, softphones, computer telephony integration (CTI), and more. These features let companies receive incoming calls efficiently; promote more effective interaction among employees; and help sales and call center organizations manage calls professionally. PBX features allow smaller companies and teams to sound and function like large enterprises.

Designed with growing business in mind, PBXtra is a feature-rich turnkey system that is scalable, fully supported, and costs 40 to 80 percent less than comparable systems.

In the traditional world, a PBX typically needs to connect to one or more PSTN (Public Switched Telephone Network) lines, Integrated Access T1/PRI lines, to make outbound calls.

In a VoIP PBX system, you can not only make outbound phone calls via PSTN, and T1/PRI, but you can also make calls via VoIP services provider (with services such as SIP Trunking).

Fonality PBXtra gives you the most flexibility to choose your telephone service type and service provider. You can choose your existing PSTN (Public Switched Telephone Network) line, an Integrated Access T1, or a VoIP service. If you use your existing PSTN line, you'll need to order a server that includes a Base Analog Expansion Card and as many Analog Line Ports (FXO ports) as you want PSTN-lines to connect. If you want to connect to a T1/PRI line, you'll need to order a system with a T1 interface card. If you choose to use a VoIP service, Fonality PBXtra provides you with the ability to use VoIP-only or a combination VoIP and PSTN service with our unique PSTN-Fallback feature. Fonality recommends that you keep at least one PSTN line active so that your main office stays operational in the event of an Internet outage.