What can a telephone system do? What kinds of features are available?
PBX (Private Branch eXchange)- A very large system suitable for campuses or corporations with multiple branches; can handle hundreds or even thousands of extensions. Allows for many advanced call-handling features. Centrex – A type of hosted PBX which is located at the central office (telephone company). It shares many of the features of a PBX without having to host any of the equipment (other than phones). The equipment must be leased from the phone company and can be quite expensive over the long-term. Key System – Smaller system, capable of supporting a few extensions to a few hundred. The features have improved to the point that the difference between a PBX and key system have blurred. Only the number of extensions, and some of the more advanced functions, separates the two. They are usually measured by the format of lines x extensions; which means a 3×8 allows three outside lines and eight internal extensions. VoIP (Voice over Internet Protocol) – Phone calls over a network such a
