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What is VoIP and How Does It Work?

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Learn more about, VoIP, how it works, and how it enables free internet calls to anywhere in the world.

What is VoIP? 

VoIP, or Voice over Internet Protocol, is a technology that allows voice or video calls to be made over the internet, rather than through a traditional landline or mobile network. This technology is not new, dating back to the 1970s when it was first tested by the US Department of Defence. 

The principle behind VoIP is simple: it works by dividing information into small packets that are transported via data networks connecting devices such as computers and smartphones. These packets are then reassembled at the receiver's end.  

It offers a completely different system to traditional phone networks, which has led to VoIP calls becoming increasingly popular for both business and personal calls that would previously have been made via a landline or mobile network. 

How does VoIP work?

To understand how VoIP works, it's important to know the different types of VoIP services offered in the UK: 

  • Device-to-Device: This form of VoIP uses your device’s microphone and speakers and is usually used on an instant messenger service. Zoom is an example of this. 
  • Device-to-telephone network: This is when the caller uses an internet-enabled device to call a landline or mobile number. Skype can be used in this way, although you’ll have to pay for calls of this kind. 
  • Telephone network-to-telephone network: With this type of service, the caller uses an adaptor to make VoIP calls from a normal landline telephone. Examples include AXvoice and Ooma. 
  • VoIP phone-to-telephone network: This is when the phone itself is IP enabled, and so there is no need for an adaptor. Services such as Vonage and BT Digital Voice include VoIP phones. 

What is VoIP used for? 

VoIP is used for making audio and video calls over the internet. It has become a popular alternative to traditional phone calls, particularly for international calls, as they are typically much cheaper with better quality sound. 

The increase in remote working has led to a lot of growth in the business use of VoIP. However, its use extends beyond the professional realm.  Many popular device-based VoIP services are free to sign up, although there may be charges to access premium features like video conferencing. Once signed up, free VoIP calls can be made to others using the same service.

If you wish to make VoIP calls to regular landline and mobile numbers, a monthly subscription or a per-minute charge may apply. However, these calls are generally much cheaper than making landline-to-landline or mobile-to-mobile phone calls. 

Can I replace my landline with VoIP?

While VoIP is a cost-effective and flexible alternative to traditional phone calls, you may still need a landline at home. If the internet goes down, a VoIP service cannot be used to contact the broadband provider – or emergency services. Many people use VoIP to complement their home phone service rather than replace it entirely.

If you want to make VoIP calls using a normal phone, VoIP home phone providers are available. They will send either a VoIP phone or a VoIP adaptor to connect your landline to the internet. However, you may often need a landline to access the internet in your homes, so you may have to continue paying landline line rental to be able to make VoIP calls. 

Some home phone providers, including BT, are making a move towards replacing all home phone services with VoIP.  

Are there any downsides to using VoIP?

Despite the many benefits of VoIP, there are a few downsides. The sound quality of VoIP calls can dip if the internet connection is poor or unavailable.

Also, certain numbers, such as directory enquiries, may not be contacted via VoIP calls. Certain calls are not possible with a VoIP service.  

However, the sound quality on a VoIP call is usually be better than a traditional landline phone, depending on the quality of the broadband connection. 

How can I set up VoIP? 

Setting up VoIP is straightforward. All you need is a device such as a smartphone, tablet, laptop, or desktop computer and a broadband or mobile data connection. Various VoIP apps or services are available in the UK, including WhatsApp, Messenger (Facebook), Skype, and Zoom. 

While we don’t currently have a VoIP comparison service, you can find a great deal on VoIP calls with one of the broadband providers we work with.  

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