There are three main types of business telephone systems: Key System Unit (KSU), Private Branch Exchange (PBX), and VoIP. All these systems use multi-keyed phones, programmable, and a licensed contractor to install. However, some telephone systems have size constraints, and some are better suited for smaller companies and others for larger companies. The purpose of this guide is to assist a buyer in the decision-making process, and we will do our best in providing the necessary information.
What is a KSU Business Telephone System?
KSU systems use a control unit (the brains) which is programmed, by a telephone contractor, to a customer’s specification. The system can manage multiple analog telephone lines, (Plain Old Telephone Service or POTS) which your local telephone company would deliver and would need connecting to the control unit.
Within the control unit is the systems software which houses the systems’ calling features. In the past, certain system manufacturers, would load basic calling features into their systems and charge additional fees for an expanded or more robust set of calling features.
The KSU business telephone system is best suited for companies that require less than forty telephones. Most business telephone system manufacturers will use a numeric scheme to identify the maximum number of phone lines and telephones a particular system can manage. As an example, a system might be specified as 8 x 24. These numbers indicate the maximum number of phone lines and telephones the system can accept, respectively.
What is a PBX Business Telephone System?
A PBX business telephone system is like a KSU in its functionality, but in other areas it far exceeds the parameters of a KSU. The main difference with a PBX is in the distinct types of circuit boards which when installed can add additional services or connectivity to the system.
The main circuit board, and the most important one, is the Central Processing Unit (CPU). The CPU holds the systems boot-up software as well as the customer’s programming. Once again, in the past, certain system manufacturers, would load basic calling features into their systems and charge additional fees for an expanded or more robust set of calling features.
The PBX business telephone system is best suited for companies that require more than forty telephones or has more than one location and desires that the two locations can communicate extension to extension without the use of the Public Switched Telephone Network (PSTN).
One of the best attributes of a PBX business telephone system is that the size constraints, which were set on KSU’s, are now specified as maximum ports allowed. These circuit cards (i.e., Central Office (CO), Digital Telephone, Analog Telephone, Voicemail, etc.), could be installed to fit a customer’s specific need. We will not go into a lot of details on each type of circuit card, but we thought it was worth mentioning that the CO card referenced above could be specialized like a T1/PRI, Loop or Ground start, or a Foreign Exchange (FX) card. So, as an example; if your company had a high demand call center, you could load the PBX with twice the number of line cards than telephone cards.
What is a VOIP Business Telephone System
A Voice over Internet Protocol (VoIP) business telephone system is really the best of the three system types. With a VoIP business telephone system, you get the full functionality of a PBX with all the calling features plus none of the major headaches that come with owning your own business telephone system. For more information on the calling features available with our VoIP business telephone system, please read Hosted PBX & VoIP brochure.
With a VoIP business telephone system, you have already eliminated the headache of not knowing when you are going to outgrow your new business telephone system. With VoIP, you can start with just one or two telephones and add additional telephones as your business grows. You can add telephones one at a time or dozens at a time it really does not matter.
The next best thing about a VoIP business telephone system is you do not have the added costs associated with the purchase of a traditional PBX telephone system. With the purchase of a KSU or PBX business telephone system you must purchase hardware (the brains) to hang on the wall in a back room in your office. This hardware purchase does not exist with a VoIP business telephone system. The VoIP hardware is housed off-premises in a secure location where it is managed, maintained, and periodically updated at no additional cost to you.
We hope that this information was helpful in determining the best business telephone system for your needs, however, if you have additional questions or concerns, please read The Business Case for Cloud-Based Phone Systems.