Virtual Call Center & Hosted PBX Terms


Abandoned Call (Inbound) – (Lost call)

The caller hangs up before reaching an agent.  Abandoned calls are available directly from ACD reports.

Abandoned Call (Outbound)

In a predictive dialing mode, this is the percentage of calls connected to a live person that are never delivered to an agent.


(Automatic Call Distributor) A computerized phone system that responds to the caller with a voice menu and connects the call to the appropriate agent.  It can also distribute calls equally to agents.  ACDs are the heart of call centers, or contact centers, which are widely used in the telephone sales and service departments of all organizations.


A general term for someone who handles telephone calls in a call center.  Other common names for the same job include operator, Telephone Service Representative (TSR), attendant, and representative.


(Average Handle Time) The period of time an employee is occupied with an incoming call.


(Automatic Number Identification) Ability to recognize the number of the person calling.  Your office must have the equipment and your network must have the ability to provide you with the calling number.


(Agent Performance Analytics)


(Average Speed of Answer) How many seconds it takes for an operator to answer a call, on average.


(Application Service Providers) Companies that remotely host software applications and provide access to and use of the applications over the Internet or a private network.  Typically, the service fee is usage based, for example, per user per month.  Although the term itself has somewhat fallen into disfavor because of the number of ASPs that were formed and then failed at the end of the dot-com bubble, today almost all outsourcing service providers rely on the ASP model for linking aspects of their services to the customer organizations.
An Open Source PBX system that is recognized as the standard by the open source development community and has proved stable, reliable and robust with the ability to accomplish and integrate with numerous feature sets.


(Analog Telephone Adapter) A device that coverts analog voice signals to digital signals which can then be transmitted over the Internet.


(All Trunks Busy) No trunks are available to handle the call, they or either being used or out of service at that moment.

Attendant console

The larger, specialized phone an operator or attendant uses to answer incoming calls and route them to the  appropriate extension.  In an IP PBX, this may be replaced by software running on a PC.

Auto Attendant

An automatic response system, such as a voice presenting options, such as press 3 for sales, 4 for parts, etc.  An attendant can handle incoming calls and directs them to the proper person, department or extension.

Automatic callback

This term can refer to a hosted PBX feature that lets employees calling from outside the office avoid long-distance charges.  The employee places a short call to the PBX, which calls the individual back using an inexpensive (VoIP) calling plan.  Confusingly, the term also refers to a feature that sets a phone to make multiple attempts to reach an unavailable number, alerting the caller when a connection is finally made.



The transmission capacity of a given device or network.

Blended Call Center

A call center that allows agents to both make and receive calls as demand and strategy dictate.  Combining automatic call distribution for incoming calls with predictive dialing for outbound calls, it makes more efficient use of an agent as each can handle the overflow of the other.


(Business Process Outsourcing) A form of outsourcing that involves the contracting of the operations and responsibilities of a specific business functions (or processes) to a third-party service provider.  Given the proximity of BPO to the information technology industry, it is also categorized as an information technology enabled service or ITES.


Call Forward

A feature that allows an incoming call to a called party, which would be otherwise unavailable, to be redirected to a mobile telephone or other telephone number where the desired called party is situated.

Call Park

Allows a person to put a call on hold at one telephone set and continue the conversation from any other telephone set.

Call Queuing

Feature that will allow an unlimited number of callers to wait for an available sales representative or for resources to become accessible to assist them.

Call Termination

A call initiated as a VoIP call is terminated using the public switched telephone network (PSTN).  The opposite of call termination is call origination, in which a call initiated from the PSTN is terminated using VoIP.  Thus, in “origination” a call originates from PSTN and goes to VoIP, while in “Termination” a call originates in VoIP and terminates to PSTN.

Call Transfer

Enables a user to relocate an existing call to another telephone or attendant console by using the transfer button and dialing the required location.

Caller ID

A telephone service that transmits a caller’s number to the called party’s telephone equipment during the ringing signal, or when the call is being set up but before the call is answered.


A telecom company that provides telecommunications circuits.  They can include local telephone companies and other telecom companies.


A term that comes from the enCOder/DECoder or Compressor-Decompressor process used for software or hardware devices that can convert a data stream.  Two VoIP codecs often used are G711, a non-compressed codec, and G729, a codec that uses compression to lower bandwidth requirements.


(Customer Premise Equipment) Equipment that resides on premise, usually at or with a business or customer.


(Customer Relationship Management) Strategy for managing and nurturing a company’s interactions with customers and sales prospects.  It involves using technology to organize, automate, and synchronize business processes.


(Computer Telephony Integration) The use of computers to manage telephone calls, allowing for automation possibilities and allows for integration of text and faxing and other services.


Data Packet

All data transmitted over the Internet uses the same basic technology.  When this data is transmitted, it is sent in blocks of digital data called packets.


(Direct dialing in) ISDN supplementary service.


(Direct Inward Dialing) A telephone number that rings in on a T1 circuit.  A T1 circuit may have tens or even hundreds of DID numbers, each one assigned to an individual.  A service that allows a company to allocate individual phone numbers to each person within its hosted PBX system.


Using a series of on/off states to represent a signal.


The creator and primary developer of Asterisk, the industry’s first open source telephony platform.  Asterisk is the basis for all Xorcom products.


(Digital Subscriber Line) Phone technology that allows a broadband internet digital connection to be carried over existing copper phone lines, while still allowing the phone service carry analog signals over the same line.

Dynamic Jitter Buffer

As a ATA receives voice packets they are stored briefly, rearranged and then processed in predefined intervals to reduce distortion.



Used in the majority of computer network connections, it is a digital networking system that involves a process known as packet switching, in which client requests are routed to their correct destination in the network.



A hardware device that converts traditional PSTN (analog/T1) signals into IP bridging the two protocols allowing them to communicate with each other.



(Inter-Asterisk eXchange protocol) An Asterisk PBX protocol, now most commonly refers to IAX2, that usually carries both signaling and data on the same path and is used to enable VoIP connections between servers as well as client-server communication.

IP Address

(Internet Protocol Address) Address of a computer that is connected to the Internet.

IP Phone

A phone that connects using Internet Protocol instead of more traditional analog lines.  An IP phone is more computer like, allowing advanced feature sets and other software functionality.


(Internet Protocol Private Branch Exchange) A hosted PBX that has the ability to send a VoIP voice stream over a LAN/WAN circuit.


(Integrated Services Digital Network) A standard digital network that lets users send voice, data and video over one telephone line from a common network interface.


(Internet Service Provider) A company that provides Internet access to consumers, allowing them to connect their computers to the Internet.


International Toll-Free Service


(Interactive Voice Response) A feature of a hosted PBX which prompts the caller with voice messages and received input from the touch tone keys.  An integrated software information system that speaks to callers and uses voice responses.  By using touchtone keypad entries to interact with the software, you get voice responses with real time data.


Key System

An office telephone system where each “outside” line appears as a button on each telephone set.  An incoming call will blink the corresponding line button on each set.



(Local Area Network) A network located in the same premise or small geographic area that is used to connect computers and other devices together through cabling or wireless connections enabling data to be sent from one point to another.


The time, usually measured in milliseconds, it takes data to travel from one point on a network to another point.


(Local Exchange Carrier) A local phone company.


An Unix-like operating system created by Linus Torvalds.  Linux enjoys a world-wide developer community with enhancements added on an ongoing basis.  Linux is distributed under the GPL (open source) license.

Live Answer

Where a person answers incoming calls and directs each call to the appropriate extension.  Compare with auto attendant.



A modem converts the serial digital (binary) data from a transmitting terminal into a form suitable for retransmission over an analog telephone channel.  A second modem reconverts this signal to binary data for acceptance by the receiving terminal.



(Network Control Center) A central location on a network where remote diagnostics and network management are controlled.


A system of computers linked together by communication channels allowing the flow of data between the linked computers.


Open Source

A licensing mechanism whereby users are allowed to use, modify, re-distribute, and even sell copies of a software program.  The only stipulation is that, if the program is re-distributed with modifications, the source code of the modifications must be provided.



(Private Automatic Branch Exchange) See PBX.


(Private Branch Exchange) A private telephone switching system that allows outside phone lines from a telecommunications provider to connect to extensions within the office or building.  They usually have multiple features including call forwarding, rollover, paging and voicemail.


(Point of Presence) A physical place where a carrier has a presence for network access.

Predictive Dialer

An automatic telephone dialing system that dials from a list of numbers and turns the call over to an agent when a human responds.  It increases productivity in a call center, because the agents can spend their time talking rather than waiting for calls to go through as well as hanging up on busy signals and answering machines.

Preview Dialing

Allows agents to review (preview) information about the contact and choose when to dial the outbound call.


(Primary Rate Interface) The ISDN equivalent of a T-1 circuit.

Progressive Dialing

Presents contact information to the call center agent prior to dialing the phone number.


(Public Switched Network) Any common carrier network that provides circuit switching between public users.


(Public Switched Telephone Network) The traditional telephone network which uses pairs of copper wire to carry analog signals or digital T1 signals carrying multiple channels.



A queue is a number of calls that are waiting to be answered by agents in an ACD queue.  The calls are usually assigned to available agents in a first-arrived, first-answered basis.  The queue is the “line up” where incoming calls wait until they are answered.  The queue sometimes refers to the group of agents available to answer incoming calls to an ACD queue.


Remote Call Pickup

Ability to remotely answer calls ringing to other extensions by dialing a feature code (i.e. *87+extension).  This allows calls to be answered prior to going into voicemail for that extension or back into a queue.


(Responsible organization) A term that refers to the company providing the telecommunications services of toll-free telephone numbers.


The way a call is passed through the Northern telephone system.  The telephone system handles the way a call is sent, and the route the call takes through the telephone system.  Different version of the Northern telephone system can route a call in different ways, according to the available routing features.



Any computer in a network whose function is to provide user access to files, printing, communications, etc.


(Session Initiation Protocol) A signaling protocol for Internet conferencing, telephony, and instant messaging.  It is a request-response protocol, dealing with requests from clients and responses from servers initiating an interactive user session.

SIP Trunking

Using SIP (Session Initiation Protocol) to connect with an ITSP (Internet Telephony Service Provider) from a PBX for primarily voice communications, which can benefit the end user with lower cost calls.  For companies to take full advantage of their premise IP-PBXs which communicate over IP within the enterprise, they can have a SIP trunk configured to connect to a traditional PSTN network though an Internet SIP connection.  The benefits can include lower monthly calling costs for long distance as well as International.


(Skills-based Call routing) A call assignment strategy utilized by many call centers.  Rather than assign calls to the next available agent, SBR assigns calls to the most suitable agent.

Stutter Tone

The type of dial tone sound created by electronic voicemail systems to let users know that a message is waiting to be retrieved. The quick-sounding alert is heard when the receiver is picked up or when the talk button is depressed to make a call.



(Transmission Control Protocol/Internet Protocol) A networking protocol that provides communications across interconnected networks, between computers with diverse hardware architectures and various operating systems.

Three Way Calling

This option allows callers to add a second outgoing call to an already connected call.

Toll Free Number

A number which you can call at absolutely no cost.  The owner of the toll-free number pays a monthly fee to their service provider.  This comes with a certain number of free minutes for the month.  Additional minutes are available for a fee.


Trunks are the physical links that enable telephone communication.  A trunk route carries calls from outside to answering positions in your ACD queue.

Trunk Line

When dealing with a PBX, trunk lines are the phone lines coming into the PBX from the telephone provider, verses extensions which typically connect to desk phones.


An IP PBX’s process of merging data from multiple calls into a single set of packets to reduce transmission overhead.



A telephone messaging system that digitizes the analog voice signals and stores them on disk or flash memory in a central computer.


(Voice over Internet Protocol) The transmission of voice over the Internet as digital packets rather than the traditional circuit-committed protocols of the PSTN.  VoIP uses real-time protocol (RTP) to help ensure the packets get delivered in a timely way.


(Voice Recognition) The ability of a machine to recognize your particular voice.



(Wide Area Network) A geographically disperse network that encompasses routers and other devices over a large area and can route that data to the proper endpoint.


(Workforce Management) Solutions that help call center managers more efficiently manage their agent workforce.

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