What is a VoIP phone?

There are plenty of abbreviations in telecom. One of them is a VoIP phone, but what is it? And how is it related to SIP? Here we tell you about the different types of VoIP phones.

First of all: What is VoIP?

VoIP stands for Voice over Internet Protocol and refers to technology that enables voice calls over the Internet. It is sometimes also called IP telephony, broadband telephony, and Internet telephony.

What is a VoIP phone?

A VoIP phone is the same thing as a SIP phone or a softphone. These are just different names for phones to make VoIP calls.


VoIP phones can be both software and hardware-based. A hardware VoIP phone works like a regular phone but can receive and make calls over the Internet instead of the traditional phone network. Software-based VoIP phones can allow computers to function as phones.


A softphone is software that you install on your computer or tablet to use the device like any other phone. It is most often used in conjunction with VoIP to make calls over the Internet.

So, what is SIP?

SIP stands for Session Initiated Protocol and is the protocol that enables telephony and VoIP services.


A SIP trunk is a virtual telephone line that uses SIP protocols to make voice calls (VoIP). Through SIP, suppliers can connect to your PBX, and all your telephone numbers are connected to the SIP trunk. A SIP session is a call or a session via a SIP trunk.


Read more: What's the difference between VoIP and SIP?

How does VoIP work?

To use VoIP, you need a VoIP phone you can use to call over the Internet. To make a call, VoIP takes an analogue voice signal and compresses it into a digital signal that is sent over the Internet as data.

Two different types of VoIP phones

A VoIP phone can be used in different ways and be both software and hardware or software, but it always involves calls over the Internet. You can use a VoIP phone to make calls to other VoIP, landlines, or mobile phones.


There are two types of VoIP phones:


1. VoIP in a landline

The simplest form is VoIP phones that work as a regular phone but are connected to your computer via USB or a wireless network, for example. This solution can be a handy solution for a conference room or a reception.


2. VoIP in mobile phones or computers (softphone)

VoIP can also work as a software program you use on your computer or as an app on your mobile. During a call, the software will set up a peer-to-peer connection to the computer you are calling.

A brief history of VoIP telephony

In the late 1970s, VoIP was developed using several different protocols. The first VoIP call outside of the analogue copper lines then went over the IP network. At that time, an NVP (Network Voice Protocol) was used over the Arpanet (the forerunner to the Internet). The first VoIP software that could be installed on home computers came in 1995.


SIP is introduced

SIP was developed in 1996 and made it possible to include video and chat. It has become the most used voice protocol compatible with IP-based PBXs and other types of VoIP products.


Many companies appreciated it as they could hold their calls over the Internet. They only needed one network for all media and could bypass physical telephone cables.


SIP trunking and VoIP today

In the early 2000s, cables and DSL connections for Internet services began to be used to a greater extent. That meant faster Internet, which in turn made VoIP technology more efficient. When VoIP became more popular, SIP trunking was a necessary function to make calls with several technologies.


Without SIP trunking, VoIP would only mean that you could make voice calls inside the office. You would still need the copper wires to make outgoing calls.


Is VoIP telephony the best telephony solution?

Calling over the Internet is the most future-proof solution (so far, anyway). VoIP telephony is suitable for most companies and industries, no matter how much you call or where you have offices.



  • VoIP stands for Voice over Internet Protocol. It is also called IP telephony, broadband telephony, and Internet telephony.
  • A VoIP phone is the same as a SIP phone or a softphone.
  • VoIP phones can be both software-based (softphone) and hardware-based.
  • A softphone is software for calling using a computer or tablet.
  • The first VoIP software that could be installed on home computers came in 1995.
  • VoIP telephony is a future-proof solution that suits most companies.

Want to know more?

Telavox can help you with everything related to SIP, VOIP, mobile telephony, and exchange services. The right PBX solution creates conditions for happier employees and more satisfied customers. Please take the opportunity to book a free demo and learn more about the possibilities!

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