PABX stands for Private Automated Branch Exchange. The other variant is PBX which is just Private Branch Exchange. Both names mean the same thing. In the past a PABX was a name given to the telephone system in a large company (more than 50 extensions). PABX systems predominantly used analogue extensions with only a few handsets having a display and programmable keys. Usually only the receptionist and perhaps the managers would have one of these phones. The receptionist would usually have a console which attached to the handset allowing them to view the status of all of the extensions in the company.
An Image of a Traditional PABX
|A phone system, other wise known as a key system or digital key system is an advanced, extremely flexible version of a PABX. Where a PABX predominantly has analogue extensions, a phone system mostly has fully functioning display handsets with only 1 or 2 analogue extensions for faxes and cordless phones.
Previously there was a clear distinction between the mostly digital phone system and the mostly analogue PABX. This line is becoming more and more faint as technology improves. The reality is that it is PABX systems that have lost their definition and the term is slowly dying.
Today’s phone systems now encorporate many of the features available on earlier PABX systems. Features such as least cost routing and auto attendant now come standard on many new phone systems. The confusion between PABX and phone systems has happened as technology advanced and merged the two names. Now PABX, PBX and phone system all mean the same thing.
Panasonic among other brands have named their latest line of phone systems as Pure IP PBX this must be for marketing purposes as the systems are not Pure IP, they are hybrid (a combination of digital, analogue and IP extensions)
To conclude – PABX, PBX, Phone system, telephone system and key system all mean the same thing. As a rough guide, A phone system with more than 200 extensions would often be referred to as a PABX. Any less than this, even if the system has the same model number, would more often than not be referred to as a phone system.