IP telephony is a technology for the delivery of voice communications over IP networks such as the Internet or other packet-switched networks.
VoIP systems employ session control protocols to control the set-up and tear-down of calls as well as audio codecs which encode speech allowing transmission over an IP network as digital audio via an audio stream.
VoIP also offers the advantage of running both voice and data communications over a single network which can represent a significant
saving in infrastructure costs.
Another advantages are:
- Location independence: only an Internet connection is needed to get a connection to a VoIP provider.
- Conference calling, IVR, call forwarding, automatic redial, and caller ID features that traditional telecommunication companies (telcos) normally charge extra for are available for free from open source VoIP implementations.
- Calling to another VoIP users and between head offices and extensions in bussiness are free.
- More scalability with a low investment for business.
- Facilitate the maintenance and increase productivity, because voice and data voice and data communications use the same network.
