IP or desk phones

What is an IP phone system?

An IP phone system (also sometimes referred to as a VoIP phone system or IP PBX) is a business phone system that functions using Voice over Internet Protocol (VoIP) technology. This allows users to take incoming calls and make outgoing calls using an internet connection. It’s an alternative to landline phone systems that you might be used to using.

With traditional phone systems, calls take place over the Public Switched Telephone Network (PSTN), which consists of copper phone lines to transmit analogue voice signals between phones. This service will no longer exist in 2025.

This type of system requires a lot of on-premises hardware (like desk phones) and office space to house the private branch exchange (PBX). It’s often referred to as the Plain Old Telephone Service (POTS).

What is the difference between an IP phone and a traditional phone?

Traditional landline phones require copper wires that you plug into wall sockets. These phones are part of a hardware-based technology system that transmits calls between two phones through switch boxes.

In contrast, IP phone systems for small business can make and receive phone calls over the internet using VoIP technology, and don’t rely on the physical exchanges that landlines do.

Types of IP business phones

There are two main types of IP phones used by organisations. These are:

  • Purpose-built hardware device (SIP phones, VoIP phones and similar) – They work in exactly the same way as a usual desk phone, the only difference is that they work by connecting to the internet.
  • Software-based softphone – Softphones can be installed on internet-connected devices like desktops, laptops, and mobile devices. You will need access to hardware such as a microphone, headset or speaker, and camera if the solution facilitates video calls—which is built into most mobile devices and laptops.

Is there a difference between VoIP and IP telephony?

You’ll often hear the terms VoIP and IP telephony used interchangeably. However, there is a difference between them.

  • IP telephony is a term used to describe any system that falls into internet-based telecommunications.
  • VoIP refers to technology that allows you to make and receive voice phone calls over the internet.