There are several different types of phone systems currently available for your business: Key systems, Private Branch Exchange (PBX), and KSU-less. The type of system you choose will depend primarily on the number of work stations where you will have phones.
Key System Unit (KSU)
Key system units use a central control unit called the key system unit (KSU). This unit allows for advanced business telephone features such as call forwarding, in office extension dialling, or voice mail options. Key systems require professional installation and maintenance. All outside telephone lines must connect to the KSU, as well as all inside extensions. Key systems are typically used for offices of fewer than 60 stations. Prices begin around $200 per station.
Private Branch Exchange (PBX) System
The PBX system is an in-house telephone switching system that interconnects telephone extensions to each other, as well as to the outside telephone network. It may include functions such as least cost routing for outside calls, call forwarding, conference calling, and call accounting. The configuration of a PBX system is totally programmable, so PBX systems can support the most complex features. But watch out - prices start anywhere from $800 to $1,000 per line.
KSU-less System
KSU-less systems contain proprietary circuitry that allows communication without requiring a central cabinet. KSU-less systems have limited features, but they have become very popular because they are easier to install since they don't require a separate pair of wires back to the KSU from each phone.
