What is Telephony? Here’s a Hint: It’s More Than Your Phone
Telephony is technology that enables interactive communication between two or more physically distant people.
Yet even as telephony evolves, questions abound. You might be wondering, what’s the best type of telephony for my business? Do I need special equipment? And how does the choice I make affect how my organization serves customers?
Here, we explain everything you need to know about telephony.
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What are the different types of telephony?
What is traditional telephony?
Traditional telephony, sometimes called “plain old telephone service” (POTS), enables conversation between physically distant people by way of the public switched telephone network (PSTN). The PSTN consists of fixed lines that connect telephones around the world via physical wiring. Imagine a call center with agents using hardwired telephones connected to wall jacks (and ultimately to the vast network of buried copper cables beyond) and you get the idea.
PSTN setups are known for their reliability but are limited in terms of flexibility. A traditional telephone line won’t accommodate video calling, for example. They’re also expensive to install and maintain.
What is mobile telephony?
Mobile telephony uses cellular technology, two-way radio waves, and radio towers to transmit sound and data wirelessly to a device.
What is internet telephony?
Internet telephony is software that changes sound into data and transmits it over high-speed computer networks. An important subset of internet telephony is Voice over Internet Protocol (VoIP), which transmits sound, video, and text messaging.
What is fax telephony?
How does traditional, mobile, and internet telephony work for business?
Traditional telephony transforms voice sounds into electronic signals and transmits them using cables, later changing the signals back into voice sounds when they arrive at their destination. In the past, the cables that transmitted the sounds were made from copper, but today, they’re increasingly fiber-optic. That’s because fiber-optic cable transmits electronic signals faster and stronger, nurturing a clearer connection.
Mobile telephony transforms voice sounds into electronic signals, transmitting them to cell towers using radio waves. Then, the cell tower transmits the radio waves using the cell tower network until they arrive at their destination, where the electronic signals are turned back into voice sounds.
Internet telephony changes voice sounds into digital signals and transmits them over broadband (high-speed) internet. VoIP can also transmit other types of communications, such as video conferencing and text messaging.
Fax telephony encodes a document as a graphic, turns it into an electric signal (traditional faxing) or data (IP faxing), and transmits that to its destination over cables or the internet. Once it arrives, the machine or the computer decodes the signal or data, creating a copy of the original document.

What are VoIP and cloud telephony, and why are they important?
Cloud telephony is a specialized type of hosted VoIP used by businesses. It’s a unified communications as a service (UCaaS) model that connects a company’s voice, video, messaging, customer relationship management, and processes together.
What are the pros and cons of VoIP for businesses?
The pros of VoIP include cost savings and greater value — as long as you have internet access, you can get free or low-cost calling, video conferencing, messaging, and faxing, often eliminating the need for a traditional PSTN line. However, during an electrical outage, you might lose access to those services if backup power isn’t available. Also, some VoIP providers don’t connect directly to emergency services like 911.
With VoIP, you can talk to anyone with a phone number, including international and mobile numbers. In most cases, the person you’re calling does not need special equipment to talk to you if you’re using VoIP.
What equipment does telephony require?
The older your telephony system is, the more equipment you’ll need — and the more you’ll need to spend to maintain it.
What’s the difference between cloud telephony and on-premises telephony?
What are different types of call center telephony solutions?
The three types of call center telephony solutions are on-premises private branch exchange (PBX), VoIP or IP PBX, and hosted VoIP.
Traditional on-premises PBX systems offer features like hold music, call transferring, call queuing, and private extensions for each employee. These systems are reliable, but also expensive — and becoming less common as they begin phasing out.
A VoIP phone system (sometimes called an IP PBX) transfers voice data between computer IP addresses. But instead of using the PSTN like a traditional PBX, VoIP systems use data networks and one or more IP PBX servers that function like a traditional switchboard.
With hosted VoIP, voice is converted into data packets, which are transmitted over the network. Instead of using servers onsite, the VoIP provider hosts the telephony in the cloud. That reduces hardware and maintenance expenses, increases the speed of installation and configuration, enables automated software updates, and eliminates the need to install cabling and wiring.

How can telephony improve customer service?
VoIP is the best solution for service teams because it increases the productivity and efficiency of your agents while also costing less money than traditional telephony. And, if you integrate VoIP with your customer relationship management (CRM) platform and digital communications channels, you empower your agents to deliver connected and seamless customer experiences from anywhere.
Here’s why. Consider that with VoIP, you can quickly scale the size of your customer service team without having to make costly investments in cabling, wiring, or desk phones — or spend money with communications providers on long-distance and overseas calls. Also, because VoIP digitizes voice data, transcribing calls is easy, automated, and instantaneous. Agents won’t have to waste time asking callers to repeat themselves, a top frustration among customers when it comes to service. When your agents have a complete view of the customer’s interactions with marketing and sales, they can give personalized answers to questions quickly. And that improves customer satisfaction.
An integrated VoIP-CRM system also gives management more insight into how service teams are performing, too, because dashboards surface important metrics like average hold time and call length. And by studying call transcripts, service organizations can find the communications most likely to satisfy customers, offering an opportunity to reskill agents as new best practices emerge.
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