Voice over IP commonly refers to the communication protocols, technologies, methodologies, and transmission techniques involved in the delivery of voice communications and multimedia sessions over Internet Protocol networks, such as the Internet. Other terms commonly associated with VoIP are IP telephony, Internet telephony, voice over broadband , broadband telephony, and broadband phone. Internet telephony refers to communications services —voice, fax, SMS, and/or voice-messaging applications— that are transported via the Internet, rather than the public switched telephone... network . The steps involved in originating a VoIP telephone call are signaling and media channel setup, digitization of the analog voice signal, encoding, packetization, and transmission as Internet Protocol packets over a packet-switched network. On the receiving side, similar steps such as reception of the IP packets, decoding of the packets and digital-to-analog conversion reproduce the original voice stream.
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