Here is a list of words and phrases you may encounter throughout your journey with Telzio and your VoIP phone system, along with their meanings.


Actions are features in a Call Flow that contain instructions for routing inbound calls. Actions include:


An API is a service that companies provide to enable outside programmers to integrate certain aspects of the company’s system into other applications.

Telzio offers an API you can use to integrate your Telzio services with your other business applications, such as CRM, help desk, and team chat programs.


An ATA is a device that enables you to use an analog phone with your Telzio VoIP service. You can use an ATA with desk phones, conference phones, and fax machines, and use them with your Telzio service.

Automated Attendant

Auto attendant is a phone feature that greets callers with menu options to be directed to the right department. Upon dialing a business, callers are prompted with a voice recording to make a selection on their keypad, which routes them to the desired party. Auto attendant service is also known as a phone menu. 


Bandwidth describes the speed of your internet connection. The more bandwidth you have, the faster your internet will be.


Callback is an option offered in the Queue settings of your Telzio phone system. While in a Queue, you can offer callers a Callback instead of holding on the phone. When it’s their turn in the Queue, the system will call your agent first, then call the caller back.

Call Barge

Call Barge enables managers to barge into agents' calls and talk to both the agent and the customer. 

Learn more about Call Barge.

Call Flow

A Call Flow is the arrangement of Actions designed to automate inbound call routing. Learn more about Call Flows.

Call Monitor

Call Monitor enables managers to listen in on agents' calls. You can listen in on calls without being heard, barge into the call, or whisper so only the agent can hear you.

Learn more about Call Monitoring.

Call Screening

Call Screening is a feature that plays a message to the agent when they've answered a call, during which time the caller continues to hear ringing. The message informs the agent which Call Flow the caller has connected to. The agent can then decide whether to accept the call or to reject it. 

Learn more about using Call Screening in your Call Flows.

Call Whisper

Call Whisper enables managers to listen in on agents' calls and speak to the agent without the customer knowing. 

Learn more about Call Whisper.


A codec is a programming tool used in VoIP to send audio data through an IP phone or softphone. Using different codecs can result in varying levels of audio quality.

Competitive Local Exchange Carrier (CLEC)

A CLEC is a telephone carrier. There are many CLECs all over the world that supply phone numbers to internet-telephone service providers (ITSPs) like Telzio.


Compression is when the size of an audio signal is reduced to take up less bandwidth, which lowers audio quality as a result. Similarly when you compress a JPEG file, the image quality becomes less clear. On the other hand, compression reduces the file size, enabling the file to load faster.

Conference Bridge

A conference bridge is a phone line that enables multiple callers to dial in at any given time to join the same call. You can add a conference bridge to any of your Telzio phone numbers.


A Destination is the User, Email, Group, Phone Number, or Call Flow where you intend to route calls, voicemails, or text messages.

IVR Menu

Interactive voice response menu (IVR) menu, or simply a Phone Menu, is an automated greeting that provides callers with options to be connected to a given destination.

Private Branch Exchange (PBX)

PBX is the hardware and/or software system that powers an organization’s phone lines and functionality – essentially, the phone system. PBX systems can be cloud based, on-premise, or a hybrid of both. Telzio is a virtual, or hosted PBX provider, which means we manage the telephone system infrastructure for our business customers.

Phone Menu

Also called an IVR Menu or Automated Attendant, a Phone Menu is an automated greeting that provides callers with options to be connected to a given destination.


A Queue is a virtual line where callers wait to be connected to the next available agent. Learn more about Queues.

SIP Trunking

In VoIP, SIP trunking connects your PBX system with your carrier services. You do not need a separate SIP trunking service to use Telzio. Telzio is your hosted PBX system, SIP trunk, and VoIP service all in one. 


In VoIP, a softswitch is a central component of a hosted PBX that enables two ends of a phone call to connect. Softswitches are built-in to your Telzio phone system, eliminating the need for you to manage softswitches and SIP trunking services.


Timeout is the amount of time a call will attempt to connect before moving onto the next destination or action. You can customize the length of the Timeout in the Forward and Queue settings of your Telzio Call Flows.


Voicemail Transcription is an included feature with your Telzio service, which enables you to receive a transcribed text version of voicemail to your email.


A User is a sub-account of your Telzio phone system, which enables employees to log into devices and the Telzio website. In VoIP, Users are also called SIP Accounts.

Learn more about Users.