Voice over IP

What is Voice over IP (VoIP)?
Voice over IP (VoIP) is the most common method for making phone calls over the internet. This is in contrast to traditional telephony, where communication is over the Public-Switched Telephone Network (PSTN).

What is the ‘IP’ in VoIP?

It standards for Internet Protocol, which gives unique addresses to every computer and other internet-connected device (either physical or virtual). This allows us to send and receive data between computers over the internet, including voice data for telephone calls.
What is the difference Between VoIP and traditional phone calls?
The main difference is that they use different networks. Traditional telephony uses the PSTN, while VoIP uses the internet.

What is the PSTN?

The PSTN is what most of us know as the phone network. It was originally a fixed-line analog network, but now the core of the PSTN is mostly digital. It consists of a mix of copper telephone lines, fibre optic cables, cellular networks and undersea cables.

As a circuit-switched network, the PSTN establishes a dedicated line between callers. This is a resource-intensive approach compared to VoIP, which sends call data over the internet to the recipient in labelled packets via the most efficient route. These packets are then re-assembled and converted back into audio so the recipient can hear what’s been said.

How does VoIP work?

In order to make a VoIP phone call, it is necessary to have a VoIP solution such as the NFON Cloud Telephone System (see figure below).


Based on this architecture, VoIP calls are delivered in three key phases. These are:

1) Audio is digitised

As you speak into your device’s microphone (laptop, mobile or headset), the audio signal is digitised by your VoIP application. This data is then broken up into pieces called packets and each is given a unique label.

2) Data travels over the internet

Your call is made up of different packets of data. Each packet of data travels over the Internet to the recipient.

3) Data is decoded and reassembled

When the data arrives at the end destination, it is put back into the correct order. The data is then converted into audio and the recipient hears what you said. 

Interestingly, the data packets don’t necessarily arrive in the order they were sent. This is because VoIP ensures that each data packet is routed to the recipient using the most efficient route across the internet.

Are VoIP calls secure?

This all depends on whether your chosen VoIP solution is hosted in a secure data centre and is able to protect your voice data with technologies such as encryption. One of the most secure VoIP solutions is the NFON Cloud Telephone System, which is hosted in geo-redundant, inland data centres. The fact that our solution is highly secure and highly available has helped us to achieve compliance with EU Electronic Communications legislation. The data centres where our solution is hosted is also fully compliant with ISO/IEC 27001 – Information Security Management standards, giving our clients total peace of mind.

Can you use VoIP to call non-VoIP users?

Yes, in the majority of cases, VoIP users can call non-VoIP mobile phones or landlines, which means you can get all the simplicity, flexibility and cost savings of VoIP, whoever you’re calling. 

VoIP solutions use something called a VoIP gateway to connect with regular mobile phones and landlines via the PSTN network. The VoIP gateway also converts calls from traditional phones into IP, so anyone in the world can call you on your VoIP phone.

How can you migrate your telephony to VoIP?

There are four main ways you can do it:

Use your PC or laptop to make and receive VoIP calls
This converts your PC into a VoIP-enabled device. Your voice, captured by the device’s microphone, is converted into data packets, sent to the recipient, and played on the speakers of their PC - or on their headset. Many VoIP solutions also give you instant messaging and video calls on your PC, with no need for additional hardware.

Use a VoIP phone
VoIP phones such as IP and SIP telephones, convert audio signals into IP packets and send them to recipients over the internet. VoIP phones typically have Ethernet connections, which means you can plug them directly into your modem or router.


Use your existing phones to make VoIP calls
If you want to use your existing telephone to make VoIP calls, you’ll need something called an Analog Telephone Adapter (ATA). This allows you to plug your phone line into a modem or router, which means that analog phone calls can be converted into IP packets and sent over the internet. Converting existing phones into IP phones can help you maximise returns on investments in existing office equipment. 

Use your mobile device to make VoIP calls
The fourth option is to make VoIP calls on your mobile device. To do this, you’ll need to download an FMC client, which allows your phone to connect into an internet telephony system. One benefit of this approach is that everyone can contact you on a single number, whether you’re at the office or on the move. The best internet telephony solutions also help you reduce costs by choosing the most efficient mobile connectivity option - whether that’s WLAN or mobile data on a carrier network. 
Another benefit of making your mobile phone an extension of your office internet telephony system is that you can consolidate two costly lines (and service providers) to a single service provider. This saves you costs and reduces supplier management admin.

What are the top VoIP use cases for business?

There are many VoIP use cases, but here are our top three:

Internal calling
With the NFON Cloud Telephone System, you can call anyone in your organisation completely free of charge, including colleagues in different offices and branches in different countries. There’s no need for expensive equipment or service provider contracts.

External calling (to fixed and mobile phones)
With the NFON Cloud Telephone System, you can reduce the cost of calling external mobile phones and landlines compared to conventional phone systems.

Placing calls from your mobile device
With the NFON FMC client, which is quick and easy to download, you can access all the features of our Could Telephone System on your mobile device. You will also have a single number for your landline and mobile, which makes it easier for colleagues and customer to reach you.

What are the benefits of VoIP?

The benefits of VoIP are many and varied, including support for new Unified Communications features and lower overall telephony costs. They include:

Lower costs
Typically, VoIP telephony is considerably more cost effective than traditional landline and mobile telephony. This is because VoIP transports voice data efficiently between callers over the internet. This is a contrast to traditional calls over the PSTN network, which require a dedicated connection for the entire call duration.

Less hardware
Because the best VoIP solutions are hosted in the cloud, they provide the full range of telephony features with no need for costly physical telecommunications infrastructure. This lowers costs while also simplifying and speeding up deployment.

Pre-integration with Unified Communications tools
The NFON Cloud Telephony System works with Unified Communications systems such as Skype for Business. This pre-integration means you can deploy video calls and other great Unified Communications features quickly and at low cost.

How can I deploy VoIP in my business?

The first requirement for deploying VoIP is a good internet connection. Everything is hosted in the cloud on our secure servers, so you can access the system with no need for complex software installation. 
How can I find out more?
NFON has prepared lots of resources to help you find out more about internet telephony and the capabilities of the NFON Cloud Telephone System. 

Further information

IP address

What is an IP address?
Internet Protocol (IP) addresses are a series of numbers separated by dots. In the same way that street addresses allow us to identify their location, IP addresses allow us to…

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Internet telephony

What is Internet Telephony?
Internet telephony refers to all features of traditional telephony (phone calls, fax, voicemail etc.) where all calls and data are sent over the Internet rather than over…

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The term “cloud” or “cloud computing” refers to a technology that allows applications and services to be accessed over a network such as the Internet as opposed to being run locally. Services made…

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