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Call Center Glossary

  A B C D E F G H I J K L M N O P Q R S T U V W X Y Z  Other


This glossary was written, complied, and edited by Peter DeHaan.




AC (Alternating Current): Standard household current, available at wall plugs and used to power most electrical devices. The most common AC Voltage is 120, although 220/240 and 440 also exist. AC is the opposite of DC (Direct Current).

ACD (Automatic Call Distributor): An ACD is commonly used to route and deliver incoming calls in call centers to agents. Compare to a PBX and switch.

Agent: A generic name for call center employees, encompassing both CSRs (Customer Service Representative for inbound calls) and TSRs (Telephone Sales Representative for outbound work).

Analog: A signal or voltage that can vary continuously between two values. Contrast to digital which can possess only two states or conditions. Speech is analog, but with modern technology, it is often converted into a digital signal to be transmitted and switched.

ANI (Automatic Number Identification): A telephone company service that provides the telephone number of the calling party (and sometimes their name) electronically to the called party while the phone is ringing. It is a more sophisticated version of caller ID.

Area Code Overlay: When a new area code is assigned to the same geographic region as the existing area code(s), which is in jeopardy of depletion. With an overlay, no one needs to change area codes. However, if it is not already implemented, ten-digit dialing becomes required for all calls, even local numbers. All new number assignments are in the new area code. As such, ordering a second line could result in a number with a different area code. Overlays are not popular with most consumers, as they do not want to dial ten digits on every call, nor remember different area codes for friends and neighbors. Contrast to an area code split.

Area Code Split: When the geographic region of the area code is divided in two. One part will keep the same area code, while the other section must switch to a new area code, but they will retain their seven-digit number. There is a transition period for this, called permissive dialing, in which either the old or new area code can be dialed for the affected section. After a time, mandatory dialing goes into effect, when any call to the new region using the old area code will not go through. These numbers eventually become available for reuse. Splits are not popular with most businesses because  it requires printing new stationary and other changes, as well as reprogramming phone systems. To avoid repeating this process in a few years, sometimes a three-way split is made at the same time. Contrast to an area code overlay.

ASP: An acronym for Application Service Provider, it refers to a company that makes software available via the Internet. The ASP handles maintenance, upgrades, and backups. End users pay a fee to use the software.

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B Channel: In ISDN service, the B channel is also called the bearer channel and is used for voice transmission. In BRI-ISDN, there are two B channels, whereas in PRI-ISDN, there are 23 B channels; all B channels use 64 kbps of bandwidth.

Bridge Clip: A small conductive metal device that is used to electrically connect a phone line from one point to another. Generally, the bridge clip is used on a "split block" and is the "demark point" between the phone company and the call center. Removing the bridge clip allows the telephone company and customer equipment to be disconnected from each other and isolated for troubleshooting.

BRI-ISDN (Basic-Rate Interface ISDN): The simple version of ISDN that allows for two main channels for voice, fax, or data and one data channel (primarily for control purposes). See ISDN; compare to PRI-ISDN.

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Call Back: A Website feature that allows a user to submit a request for an agent to call them. Compare to the “talk-to-me” feature, which uses VoIP to establish a phone connection over the Internet.

Call Center: Any centralized location to which calls can be directed, answered, and processed. However, in common usage it also encompasses operations that may be decentralized and that process more than calls. Contact center is a broader term that is often substituted for call center

CAP (Competitve Access Provider): See CLEC (Competitve Local Exchange Carrier).

Central Office (CO): A telephone company facility where customers' lines are connected to switching equipment so that they can call other numbers, both locally and long distance.

CLEC (Competitive Local Exchanged Carrier): A relatively new telephone company, competing with the entrenched local telephone company (called ILECs) who used to be a protected monopoly. CLECs are believed to meet customer needs and drive innovation much better than the traditional telephone company. CLECs serve to push down prices for local telephone service. They are also called CAPs (Competitive Access Providers); compare to LEC and ILEC.

Client: A customer of an outsource call center.

Conference: A procedure where three or more people are connected together on a telephone call and can talk simultaneously to one another.

Contact Center: A newer name for a call center, reflecting that other forms of contact (email, fax, text chat, Internet call back, VoIP, and even regular mail) are handled in addition to phone calls.

CSR (Customer Service Representative): An employee of a call center tasked with providing phone support to customers who call for assistance. See agent and contrast to TSR.

CSU/DSU (Channel Services Unit/Digital Services Unit): A device that is the demark point and interface used between equipment and a digital circuit, typically a T-1 or ISDN circuit. It offers protection and serves as a diagnostic point.

CTI (Computer-Telephony Integration): Integrating a computer system with a telephone switch to allow relevant computer database information about the caller or account to be presented to the CSR simultaneously with the call. The telemessaging industry enjoyed basic CTI functions with its first computerized systems in the mid 1980s, years before it was introduced to the general business market. Now, more sophisticated second-generation CTI platforms are common, representing the leading edge of technology.

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D Channel: In ISDN service, the D channel is also called the delta channel and is used for control and signaling functions. In BRI-ISDN, the D-channel is 16 kHz of bandwidth; in PRI-ISDN, the D-channel is 64 KHz of bandwidth.

DC (Direct Current): A steady flow of electricity in one direction; it is the opposite of alternating current (AC). Power supplies in equipment often run on AC, but convert it to DC. Telephony switches, especially Central Offices, make extensive use of 48 Volts DC. The 48 Volts DC is what provides the “talk battery” on a telephone.

Decision Tree Software: A computer software program that presents a series of predetermined questions, each based on the answer of the previous question, allowing the user, or agent, to reach a correct decision even though they do not personally have the expertise required to make such a decision. See help desk.

Dedicated 800 Service: The opposite of switched 800 service whereby the 800 numbers are permanently connected to the customer’s switch, usually via T-1.

DID (Direct-Inward-Dial): A special telephone service in which there is no direct relationship between one line and a specific telephone number, but where many different numbers can be served by the same trunk or group of trunks. To specify which number was called, identifying digits are dialed on the trunk and decoded by the equipment. By definition, calls can only be received with this type of service, however, many phone companies have enhanced DID service so that calls can be made on DID trunks as well. This allows for greater efficiency (since they can be used for two purposes) and also a higher quality patch (since it is switched and handled by the phone company’s central office). This is called two-way DID, but it is not available from all phone companies or from all central offices.

DID Numbers: A group of usually consecutive numbers, often in multiples of 20 or 100 that are used for DID service. The numbers have no unique physical line and calls cannot be placed on a DID number.

DID Trunks: The physical lines that DID calls are received on. Many DID numbers can be handled on a few DID trunks. Although phone companies and telephony engineers often recommend ratios as low as one trunk for each six numbers, the common reality for the telemessaging industry is a much higher ratio, such as 1:25.

Digital: The representation of information in a two state format, either “on” or “off,” 1 or 0. Computer programs, information, and instructions all exist in digital form. Speech, although an analog waveform, is often converted into a digital format for transmission or storage (such as in a voice mail system). The electrical transmission and switching of speech in digital form provides greater overall quality and less noise than doing so in analog form. Most modern switches are digital switches and represent improved quality over older analog switches.

Digital Switch: The device that directs or routes calls. As the name implies, all phone calls are processed as digital signals. A digital switch is more advanced and produces higher quality connections that are less prone to noise. Virtually all switches currently on the market today are digital switches.

DS-1: See T-1.

DS-3: See T-3.

DSL (Digital Subscriber Line): A transmission protocol that allows data to be sent over standard copper wires at high speeds. There are several different types of DSL service, such as ADSL and VDSL, each providing different transmission speeds. DSL is often used for Internet access.

DTMF (Dual-Tone, Multi-Frequency): Also known by the AT&T registered trademark of Touch-tone. It is a method of placing a call whereby a unique pair of tones are used to represent each digit of the phone number.

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Email: A text form of communication, analogous to voice mail. Anything that can be stored on a computer can be sent from one email address to another. Email that has access to the Internet can send a message to any other Internet email address anywhere in the world. Generally, email messages are short, informal typed messages. However, they can also be long or formal and can contain attached files and pictures.

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Fax Server: An external device that accepts client messages from a telemessaging platform, converts them into the format used by fax machines, and delivers them to the client's fax machine. Many fax delivery units have been expanded to send alphanumeric pages and email messages as well.

Flat Rate Service: A phone company designation indicating that an unlimited number of local and/or long distance calls are included in the monthly service fee. Compare to measured rate service.

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Generator: A device to produce electricity to run equipment in the event that commercial power is lost. Generators are powered by gasoline, propane, or natural gas and produce the AC power required to run electrical equipment. Generators are sometimes used in conjunction with or as an adjunct to UPS (Uninterruptible Power Supplies).

Gigabyte: A measurement of computer memory capacity, a gigabyte is one billion bytes of data or 1,000 megabytes. Sometimes incorrectly shortened to “gig” or “gigs.”

Gigahertz: A measurement of transmission frequency, either over the airwaves or through a conduit such as a fiber optic or network cable. One gigahertz is one billion times a second or 1,000 megahertz.

Ground Start Lines: An alternative type of business line that requires the circuit to be electrically grounded before answering or placing a call. It is not common, but is considered superior to its ubiquitous cousin, the loop start line.

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Headset: A hands-free device allowing one to talk on the phone and yet keep both hands available for typing. Headsets are highly recommended for call center agents.

Headset Box: A network interface box into which a headset amplifier is plugged. A headset box is connected to the phone system (be it a PBX, ACD, or switch). Some equipment allows a headset to be directly connected without the need for a headset box.

Help Desk: A segment of the call center industry, whereby entry-level staff can use decision tree software to answer questions and provide basic support functions for technical applications.

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ILEC (Incumbent Local Exchange Carrier): One of the original local phone companies that resulted when the Bell System was broken up in 1984. See LEC; compare to CLEC.

IM: See Instant Messaging.

Inbound Telemarketing: One of two aspects of telemarketing where customers or prospects call a company for assistance when they want or need it as opposed to outbound telemarketing where the company calls customers or prospects.

Instant Messaging (IM): Commercial versions of text chat that allows Internet users to type messages to one another. There are several competing instant messaging services, which have varying degrees of compatibility with each other.

InterLATA: Literally, between LATAs. InterLATA traffic is generally the domain of the long distance carriers (IXCs).

Internet: A complex international network of networks, allowing email and information to be readily sent from one computer to another. Several different services are available on the Internet, including email and the World Wide Web.

Internet Telephony: See VoIP (Voice Over Internet Protocol).

IntraLATA: Literally, inside the LATA. IntraLATA traffic is generally the domain of the local telephone companies (known as generally as LECs or specifically as ILECs and CLECs). See LATA and contrast to InterLATA.

IP Telephony (Internet Protocol Telephony): See VoIP (Voice Over Internet Protocol).

ISDN (Integrated Services Digital Network): An international standard for all digital telephony communication. There are two types of ISDN: BRI-ISDN and PRI-ISDN.

IVR (Interactive Voice Response): A computerized system that allows callers to interact with and receive information from a database using touch-tone signals. The information is provided audibly using text-to-speech conversion. Some IVR systems will also recognize basic speech instead of requiring callers to press keys on their telephone.

IXC (Inter eXchange Carrier): A telephone company that does not provide local telephone service, but which does provide long distance service.

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Last Mile: A term referring to the final leg in connecting a home or business to the public switched telephone network (PSTN). Traditionally this was and often still is done via a pair of copper wires, though it can also be coaxial cable, fiber optics, or even wireless transmission. Although new technologies are implemented in central offices and in distribution networks, it is the last mile that is the last to be upgraded. See local loop.

LATA (Local Access and Transport Area): In most cases the LATA was essentially the area code. However, with area code splits and overlays this simplification is losing clarity. A LATA is the geographic area in which the local phone companies can generally handle calls without assistance from long distance companies (IXCs). A LATA serves as a legal limitation as opposed to a technical constraint.

LDAP: An acronym for Lightweight Directory Access Protocol, which defines a standard for organizing directory hierarchies and interfacing to directory servers.

LEC (Local Exchange Carrier): The local phone company. LECs used to be a protected monopoly (and some still are). See CLEC (Competitve Local Exchange Carrier) and ILEC (Incumbent Local Exchange Carrier) for two types of LECs.

Live: A somewhat inane term to indicate that a call will be processed by a real person as opposed to automation from an IVR platform, voice mail system, or an answering machine. Although call automation is preferred in some circumstances, most consumers prefer to interact with a person, presuming that that person is trained and empowered to assist them.

Local Loop: The connection between the local phone company and a business or residence. This is comparable to, but more encompassing then, the last mile.

Loop Start Lines: A standard business line, in which a circuit needs to be closed in order to get dial tone or answer a call. Most individual phone lines are loop start. Compare to the less common ground start line.

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Measured Rate Service: A phone company designation indicating that each local call is counted (measured) and billed to the calling party. Businesses in many areas are on a measured rate, though some enjoy a flat rate service where an unlimited number of calls can be placed without incurring an additional charge.

Megabyte: A measurement of computer memory capacity, it is one million bytes of data. It is often incorrectly shortened to “meg” or “megs.”

Megahertz (MHz): A measurement of transmission frequency, either over the airwaves or through a copper wire; also, a measurement of the clock speed on a computer. One megahertz is one million times a second.

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ODBC: An acronym for Open Database Connectivity and is a database standard. Any database that is ODBC compliant can connect to any other database that is ODBC compliant.

OPX (Off-Premise Extension): A service that functions identically to a residential extension, but with the extension at a different location. Once the primary method of connecting clients to telephone answering services, call forwarding is generally the connection method of choice, due to increased flexibility and lower cost.

Outbound Telemarketing: One of two aspects of telemarketing whereby a company proactively calls consumers or businesses in order to make sales. Contrast to inbound telemarketing.

Outsource Call Center: A call center that provides various call answering and call processing services to third parties for a fee. Sometimes called Teleservice Companies or a Service Bureau. This term is sometimes also used to encompass telephone answering services or telemessaging services. See Outsourcer.

Outsourcer: A call center that processes calls for other companies.

Outsourcing: The concept of taking internal company functions and paying an outside firm to handle them. Outsourcing is done to save money, improve quality, or free company resources for other activities. Outsourcing was first done in the data-processing industry and has spread to areas, including telemessaging and call centers. Outsourcing is the wave of the future.

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Patch Cord: A short cable often used in a patch panel, to easily and quickly connect two points together.

Patch Panel: A junction or interface where telephone lines or computer network cables can be easily and quickly connected or moved using short patch cords. A patch panel saves time and costs when installing or reconfiguring telephone or computer access.

Patching: A method of connecting two callers together. See conference.

PBX: A phone system that has many of the same capabilities as a phone company’s central office. A PBX is sometimes referred to as a switch. Most larger businesses have a PBX. Contrast to an ACD found in most call centers.

PIC (Primary InterLATA Carrier): A designation for a main, or default, long distance company. Although it is an oxymoron, some areas allow an IntraLATA PIC to select a long distance carrier for calls made within the LATA.

Port: A generic name for the portion of a card that connects with a line, trunk, network, or computer peripheral.

POTS (Plain Old Telephone Service): Traditional phone service that is found in most homes and businesses. POTS is in contrast to advanced services such as ISDN and DSL, which are digital and provide greater bandwidth.

PRI-ISDN (Primary-Rate Interface ISDN): A high capacity version of ISDN that allows for twenty-three main channels (for voice, fax, or data) and one data channel (primarily for control purposes).

PSTN (Public Switched Telephone Network): The traditional international telephone system in which phone calls are switched or routed from origin to destination. This is in contrast to private networks and dedicated point-to-point services.

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Queue: A stack of calls on hold, or ringing, and waiting to be answered. Most call centers make use of a queue for increased agent efficiency and productivity.

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Rep (Representative): Another name for agent; see CSR and TSR.

RJ-11 (Registered Jack 11): A standard modular jack used for to connect a single phone line. In alternate variations, it can also handle two or three lines.

RJ-45 (Registered Jack 45): A standard modular jack used for many computer network connections. It can accommodate eight wires, although all eight may not be used or needed in certain network configurations.

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Screen Pop: In CTI (Computer-Telephony Integration) applications, causing a computer to display information about the call at the same time as the CSR answers the call.

SS7 (Signaling System 7): A sophisticated telecommunications protocol that provides out-of-band signaling and a data interface between phone company switches for the express purpose of reducing congestion in the PSTN (Public Switched Telephone Network). For example, without SS7, a long distance call is routed through the network to the called party to make their phone ring or before a busy signal can be returned, thereby tying up circuits along the entire path. With SS7, once the call is dialed, the data interface sends a message to the end switch to ring the phone or to check if the called party is busy before the call is routed. If the call is answered, it is then immediately routed though the network, thereby not using the circuits while the phone is ringing or in busy and no-answer situations.

Surge Suppressor: An electronic device that limits the damaging effect of surges on electronic equipment from commercial power plants, generators, and electrical storms. All important or expensive equipment should be plugged into a surge suppressor.

Switch: A generic name referring to any device that can connect lines or trunks and route calls from port to another. It can be analog or digital. Digital is more advanced and produces higher quality connections that are less prone to noise. See ACD and PBX.

Switched 800 Service: In the past all 800 numbers required expensive dedicated lines. With switched 800 service, the long distance company routes 800 calls to existing local telephone lines. This is efficient and cost-effective for low volume applications. Also, since 800 numbers cannot have call forwarding on them, the switched 800 service can effectively be rerouted by forwarding the local lines they ring in on. Contrast to Dedicated 800 Service.

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T-1: In common usage T-1 is a designation for a high speed, four-wire data circuit that can accommodate up to 24 separate audio channels. Technically, T-1 is the medium and DS-1 (not to be confused with DSL) is the format, though in many instances the terms are used interchangeably. A T-1 circuit is also a common high-speed Internet connection.

T-3: In common usage, a designation for a very high speed, four-wire data circuit that can accommodate up to 28 T-1 circuits, which is 672 separate audio channels. Technically T-3 is the medium and DS-3 is the format, though in many instances the terms are used interchangeably. A T-3 circuit is also used in connecting to the Internet backbone and even for some Internet backbones.

Telco: Short for Telephone Company.

Telecommunications: Communications that take place using the telephone or telephone network.

Telemarketing: Sales and service conducted using the telephone. It is classified as inbound or outbound. See inbound telemarketing and outbound telemarketing.

Telemessaging: The act of answering a call, taking a message, processing that information, and relaying it to the client.

Telephone Answering Service: A business that handles calls for clients at a central location, whereby a client's phone is answered, a message is taken or information provided to the caller, and the results are documented and provided to the client. Many telephone answering services also provide voice mail service and enhanced services, such as order taking.

Telephony: A term used to refer to telephone lines, trunks, circuits, related equipment, and the information (voice, fax, and data) that is transmitted over them.

Telephony Switch: See switch.

Teleservice Company:  See Outsource Call Center

Text Chat: An Internet service that allows two (or more) users to type messages and immediately send to each other. Text chat is a real-time communication; compare to email, which is not. Instant Messaging (IM) is a subset of text chat.

Touch Tone: A dialing method that uses tones as opposed to dial-pulses. Today most phone lines are designed for touch-tone dialing (which is faster and more reliable). Many touch-tone lines will also accept dial pulse signaling, but this is not always the case. Touch-tone is a trademark of AT&T; the generic name is DTMF.

TSR (Telephone Sales Representative): A term commonly used in the telemarketing and call center industries for employees who proactively place calls to customers or prospects to obtain data, share information, or sell products and services. See agent and contrast to CSR. Some define TSR to stand for Telephone Service Representative, though CSR is a more universally accepted term for that context.

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Unified Messaging: A system that allows voice mail, email, and faxes to be received, stored, and retrieved from a common system using various interfaces, including a phone, fax machine, or computer.

UPS (Uninterruptible Power Supply): A device that supplies continuous power to computers and switches by converting energy stored in batteries to 120 Volts AC. Commercial power is used to charge the batteries. In the event that commercial power is lost, a UPS will provide power until the batteries run down, commercial power is restored, or a generator is turned on. In many installations, a UPS is used for short-term outages and gives time for the generator to be started and stabilized to power equipment during prolonged power outages.

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Voice Logging: Recording phone calls in a call center. Voice logging systems can be hardware based or software only. Most systems record only agent phone calls, whereas others record all audio continuously. Some systems can be linked to call records and even screen displays to provide a complete picture of the phone call. Voice logging is useful for call verification, agent training, and customer service resolution. In some industries voice logging is required. Also, laws regarding the legality of voice logging vary from state to state and country to country.

Voice Mail: A device that plays announcements to callers, records messages, and allows the messages to be retrieved. There are hundreds of different voice mail systems, each with slightly different features and user interfaces. Many newer voice mail systems provide aspects of unified messaging, which allow voice mail, email, and faxes to be handled on a single platform.

VoIP (Voice Over IP or Voice Over Internet Protocol): Using the Internet to send voice signals or phone calls. Also referred to as Internet Telephony or IP Telephony.

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24 x 7: A notation to indicate continuous operations, twenty-four hours a day, seven days a week. Most teleservice companies and outsourcing call centers operate 24 x 7.

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