What does VoIP phone mean?

A VoIP phone is a kind of telephone that uses IP technology to transmit calls. It can come either in the form of specialized digital hardware or a program (running on a computer or mobile device) that performs the same functions.

With its microphone and receiver, a VoIP telephone takes the sound you generate and converts it into packets of data, which it sends over the network and out through the internet. On the other end, the phone decompresses the data and plays it back for the other person to hear.

VoIP vs traditional phone systems

In the case of business phone systems, a traditional phone is connected via a wire to an on-premise private branch exchange (PBX)—the bulky equipment that allows the system to connect all internal extensions. In this office phone setup, the PBX is essentially the brains of the system since it manages all routing and ensures all calls reach their destination through the public switched telephone network (PSTN). Also, Take a look at Spectrum Phone Number.

Benefits of VoIP phone system

With a Business VoIP phone system, you no longer have to keep IP PBX hardware inside your office premises. You can choose to have it hosted so that you’ll get all the enterprise-level functionality you need in a phone system without having to worry about the overhead costs of maintaining a server inside your building.

What is a VoIP phone and how does it work?

Before you can understand how VoIP telephones transmit calls over the internet, you have to first understand how VoIP technology works. 

Voice over IP technology is actually a set of different protocols working together to replicate telephony functions. Each protocol has a different function but all are working simultaneously in real-time.

Session Initiation Protocol or SIP

The general purpose of SIP is to set up real-time multimedia sessions between two or more participants over the internet. In VoIP, this protocol is the signaling component of the technology. It:

  • initiates the call (when you dial a phone number)
  • establishes connection (when the person being called answers the phone), and
  • terminates the connection (when either of the participants drop the call).

While there are more complex processes going on to establish these connections, that is basically what SIP does for VoIP.

Real-time Transport Protocol or RTP

RTP, on the other hand, is the one responsible for carrying multimedia; which in the case of VoIP is voice audio, over the internet. It carries the digital voice audio data packet back and forth during VoIP phone calls. After which, codecs then convert the compressed digital audio data packet to uncompressed audio so that it can be played or heard by the call participants. There are many different types of codecs, which can affect call quality and clarity. RingCentral, in particular, supports G.722 audio codec and OPUS audio codec for HD voice.

Transport protocols for VoIP

Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) are the two primary types of transport protocols used for data transmission across the internet. How does one differ from the other?

As previously mentioned, data travels over the internet in packets. These data packets are transmitted using the IP network. Imagine sending a letter—you need an envelope to make sure it is delivered to its destination untouched and without delay. TCP and UDP are two kinds of envelope you can use, and both carry the voice signals in the form of data packets.