A basic business telephony system is a multi-line telephone system where the central office lines are accessible from multiple telephone extensions. Primary calling functions include local call services and international long distance call services. But with time, as the technology evolved, the basic telephony services have progressively merged, bringing benefits for Computer Telephony Integration (CTI); as a result new communication and collaboration tools like instant text and video messaging, application based call services, emails and desktop sharing became more efficient and suitable tool for businesses. As of today business telephony system includes following services like:
Fig: Business Telephony Services