IP telephony is any phone system that runs on the internet instead of traditional landlines. In other words, it uses internet protocol (IP) to send and receive voice transmissions. Voice over IP (VoIP) is another term for IP telephony.
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F A Q | IP Telephony
IP telephony digitally transmits voice calls over an IP network. This allows you to make and receive business calls through the internet.
The main difference between VoIP and traditional telephony is that VoIP uses the internet to transmit voice calls while traditional telephony uses physical landline connections.
Cost savings is one of the biggest advantages of using IP telephony over a traditional phone system. You can save on international and long-distance calling costs as well as monthly costs.