IP refers to Voice over IP or Internet Protocol. This basically means that you do not have to use your regular telephone network to make calls but can do the same over a LAN or a local network and also over the Internet. In IP telephony packet switched connections are used to transfer information in the form of voice or fax instead of the conventional PSTN or public switched telephone network. IP telephony allows users to make local as well as long distance calls. Since these calls are not yet regulated by most governments around the world; it provides users a cheap mode of communication.
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