Today such components of telephone industry as IP telephony, VoIP, PBX, IP PBX are used interchangeably by many people, but difference between these telephone systems is distinct.
VoIP and IP Telephony
IP telephony (Internet Protocol telephony) is a general term for the technologies that use the Internet Protocol's packet-switched connections to exchange voice, fax, and other forms of information that have traditionally been carried over the dedicated circuit-switched connections of the public switched telephone network (PSTN). VoIP is a subset of IP Telephony. IP Telephony, also commonly called Internet Telephony, is the area of communications that involves digital phone systems based on a number of IP (Internet) standards. It is a way of making a phone system digital in a way to take advantage of the Internet and of any hardware and applications attached to. The main aim of IP Telephony is to increase productivity, which suggests that the technology is better referenced in business environments. On the other hand, VoIP is simply a digital transport vehicle for phone calls. In its different flavors, it works towards offering cheap or free calls and to add more features to voice communications. To see it in a broader picture, think of IP Telephony as the overall concept and VoIP as a means of transmitting voice to implement this concept.
PBX and IP PBX
Traditional PBX or analogue phone systems exist as a physical exchange box on your company's premises. Here, a phone box is used that connects all the on-site phone lines (ISDN lines), the costs are usually higher due to installation, down time and maintenance and support. As traditional free virtual PBX systems tend to be more complex and bespoke it requires a certified engineer to fix any issues Even so, if cost is an issue, remember that hardware needs to be maintained and upgraded. Virtual PBX system hardware can quickly become obsolete in today’s digital climate. Many businesses with offices that are spread out around the country prefer the IP PBX platform because it treats all callers as if they are in the same office building. Consequently, there is considerable cost-savings to be enjoyed from this model. The IP PBX platform makes use of the Internet so it is a bit of a hybrid when it comes to telecommunications technology.
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