VoIP (voice over IP) VoIP (voice over IP) is the transmission of voice and multimedia content over Internet Protocol (IP) networks. VoIP is enabled by a group of technologies and methodologies used to deliver voice communications over the internet, enterprise local area networks or wide area networks. VoIP historically referred to using IP to connect private branch exchanges (PBXs), but the term is now used interchangeable with IP telephony. How does VoIP work? VoIP encapsulates audio ...