IP Telephony: Private Branch Exchange(PBX) vs. VoIP
Contributed by Billy Short
Internet Protocol telephony (frequently referred to as IP telephony) is an important concept in enterprise communications technology. IP telephony refers to all real-time applications over IP, which include many different instant messaging programs, video-conferencing, fax services, and Voice over Internet Protocol (VoIP). This document will focus mostly on the VoIP aspect of IP telephony.
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