Key Telephone System (KTS)

A Key Telephone System (KTS) is the traditional phone system having phones with multiple keys/buttons and lights that indicate which line(s) are in use at any given time and typically have one attendant phone or separate box that acts as controller for a limited number of lines and extensions. A key telephone system is in the same category as a PBX (private branch exchange). You will often see equipment categorized as PBX/Key. Key telephone systems rely on the telephone company switching equipment, while PBX systems rely on a central control unit located at the business-customer’s location.

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