IP telephony refers to any phone system that uses an internet connection to send and receive voice data. Unlike a regular telephone that uses landlines to transmit analog signals, IP phones connect to the internet via a router and modem. The first publicly available IP phone arrived on the market as early as 1995. But, compared to a standard phone system, it had low audio quality and was prohibitively expensive.
Since then, internet-based phone technology has improved by leaps and bounds. IP telephony now offers HD voice quality, cheaper running costs, and advanced business phone features. And the need for up-front investment is next to nothing.
In this article, we’ll give you a complete breakdown of IP telephony.
IP telephone systems use the Internet Protocol (IP) or other digital protocols to transfer voice communications over the internet.
If you use an IP PBX system, the data is transferred digitally on a Local Area Network (LAN), and then transformed to analog voice signals and sent to the PSTN.
Hosted VoIP has become the most popular IP telephony solution. It lets businesses take advantage of advanced PBX features without hardware installed on-site.
With hosted VoIP, your IP phone sends digital data over the internet to your provider. Your provider handles the routing of calls, call queues, and everything else in the cloud.
You can also use SIP trunking to connect a legacy IP PBX to a modern VoIP provider to take advantage of missing features.
The terms are often used interchangeably, but there is a subtle difference between them.
IP telephony describes any system that fits within the internet-based telecommunications umbrella, including fax and other systems.
Initially, the term VoIP (Voice over Internet Protocol) was more specific. It only referred to the technology used to make and receive phone calls over the internet.
In recent years, though, even VoIP providers and telecommunications companies have started to use these terms interchangeably. IP telephony and VoIP both cover phone systems that use a LAN (local area network) to connect to the internet via a modem/router.
IP telephony relies on a variety of open-source protocols to transfer data from the phone to the service provider.
Here are the three most common:
Which protocols IP telephony uses depends on how your phone system is set up as well as your VoIP provider.
To effectively send voice data over the internet, you need a way to compress and decompress it. Because phones stream data in real-time and the focus is on human voices, they can’t use general codecs like MP3.
Most IP telephony service providers, including Nextiva, use the specialized G.711μ codec — the same as the new digitized PSTN. You can check out our more in-depth guide on VoIP codecs if you’re interested in learning how they affect your call quality.
VoIP telephony is taking over the business telecommunications market. Over 79% of US businesses use VoIP phones for at least one location.
Why are so many businesses making the switch?
There are a few primary benefits.
For starters, VoIP is significantly cheaper than traditional business plans.
Switching to an unlimited VoIP plan can save you up to 60% over a comparable business landline plan.
Nextiva Basic, for instance, starts at $20/month per line and includes unlimited calling in the US, Canada, and Puerto Rico.
IP telephony also enables your business to access advanced features without having to invest in extra hardware.
For example:
With Nextiva, you can choose advanced enterprise plans that include all our VoIP features or upgrade your plan with the necessities you need.
VoIP also makes it a lot easier to integrate voice communications with your CRM and other business tools.
The ability to centralize data and provide consistent customer service across multiple channels (at a lower cost) makes IP telephony and VoIP a no-brainer for many businesses.