Voice over IP is the same as Voice over Internet Protocol, and is better known as VoIP.

VoIP refers to the diffusion of voice traffic over Internet-based networks. Internet Protocol is originally designed for data networking and following its success, the protocol has been adapted to voice networking.

VoIP can facilitate tasks and deliver services that might be cumbersome or costly to implement when using traditional PSTN:

• More than one phone call can be transmitted on the same broadband phone line. As the result, VoIP can facilitate the addition of telephone lines to businesses.
• Features that are usually charged extra by telecommunication companies, such as call forwarding, caller ID or automatic redialing, are simple with voice over IP technology.
• Unified communications are secured with VoIP technology, as it allows integration with other services available on the Internet such as video conversation, messaging etc.