Glossary
Access charge
A monthly fee imposed by the Federal Communications Commission on all phone customers (except Lifeline customers) for access to the long distance network. It’s also called a network access charge.
Analog
A transmission method using continuous electrical signals that vary in amplitude or frequency in response to changes in sound, light, pressure, or position.
Average revenue per user (ARPU)
A measure of revenue on a per user or subscriber basis (revenue divided by the number of subscribers). ARPU allows companies to track revenue sources and growth.
Backbone
The large transmission line that carries data gathered from small lines that interconnect with it.
Bandwidth
The smallest range of frequencies that can be transmitted without distortion. It’s measured as the number of bits that can be transferred per second. Greater bandwidths have a higher information carrying capacity.
Bell System
A term for AT&T prior to its 1984 divestiture, which included 24 Bell operating companies providing local exchange phone service, the AT&T Long Lines Division providing long distance connections, equipment manufacturing (Western Electric), and a research and development arm (Bell Laboratories).
Bit
The smallest unit of digital information utilized by electronic or optical information processing, storage, or transmission systems. Bit is short for binary digit. Binary technology is based on the representation of data with 0s and 1s, whose combinations form a protocol medium for all data transmission.
Bundles
A marketing strategy that involves offering several different products for sale as one combined product. The rate structure provides a financial or other benefit that is usually contingent on the use, consumption, or subscription to all the service elements in the bundle.
Byte
A byte consists of eight bits and represents the amount of data of a number or letter. It’s also the smallest unit of information that a computer system can locate within its data storage or memory.
Carrier
A telecom provider that owns circuit-switching equipment. In contrast, resellers provide phone services but don’t own the switching equipment. Also called a service provider.
CDMA (code division multiple access)
A spread spectrum air interface protocol that uses radio frequencies to provide mobile telecom services, including interoperability with the wireline PSTN (public switched telephone network). CDMA was developed by Qualcomm and is one of three main protocol implementations used in delivering mobile voice services.
Churn rate
A measure of customer turnover. It’s used especially in the mobile telephony or Internet access markets and is usually measured as a rate per month. The calculation is the number of subscribers that terminated service divided by the average number of customers in the network during the period.
Circuit switching
A switching system in which a dedicated physical circuit path exists between a sender and receiver for the duration of the call.
CLEC (competitive local exchange carrier)
A company that provides local wireline phone service and competes with an incumbent local exchange carrier (ILEC). CLECs were formed in response to the Telecom Act of 1996, which aimed to increase local carrier competition.
Coaxial cable (coax)
A copper wire surrounded by insulation which is itself surrounded by a grounded shield of braided wire. The coax minimizes electrical and radio frequency interference. Coaxial cable is the most common type of cabling used for network access lines that deliver television and other audio-visual signals into customer premises.
Common carrier
A company offering telecommunications services or facilities to the public.
Cramming
Adding services and charges for enhanced features such as voicemail, caller ID, and call-waiting that customers have not ordered.
Data compression
Techniques (usually mathematic algorithms) to reduce data’s size so less disk space storage and transmission time is required to manage it.
Default carrier
A customer’s direct dial carrier. By calling 1-700-555-4141, a caller can identify his default carrier.
Digital Subscriber Line (DSL)
A generic name for a group of enhanced speed digital services provided by telephone service providers. DSL services run on twisted-pair wires; they carry both voice and data.
Ethernet
A networking protocol developed by Xerox Corp. that is used in local area networks (LANs).
Exchange
A unit generally smaller than a LATA, established by the local exchange carrier (LEC) for the administration of communications service in a specified area (usually a city, town, or village and its environs). An exchange consists of one or more central offices together with the associated facilities used to provide communications services within that area. Multiple exchanges make up a LATA.
Facilities
Transmission lines, switches, and other physical components used to provide telephone service.
Federal Communications Commission (FCC)
An independent agency of the US government, which was established by the Communications Act of 1934 to regulate the Telecom sector. It oversees licenses, rates, tariffs, standards, limitations, and so on.
Federal Subscriber Line Charge
Also know as a Federal Access Charge, Customer Line Charge, Interstate Access Charge, Interstate Single Line Charge, FCC Approved Customer Line Charge, Subscriber Line Charge, or SLC. It’s a federally mandated charge billed by local telephone companies and pays part of the cost of supplying a phone line to a home or business to the local telephone company. It is designed to help local phone companies recover the cost of providing “local loops.” It’s not a tax, but a charge that is part of the price you pay to your local telephone company. Neither the FCC nor any other government agency receives the Federal Subscriber Line Charge, and the FCC places a cap on the charge.
Fiber optics
Technology based on transferring information over thin filaments of glass or other transparent materials. Coded light pulses that represent data, image, and sound are transmitted at higher speeds than more conventional materials, like copper.
GSM (global system for mobile)
GSM is the most popular standard for mobile telephony systems in the world. GSM differs from its predecessor technologies in that both signaling and speech channels are digital, and thus GSM is considered a second generation (2G) mobile phone system.
High definition television (HDTV)
An improved television system which provides video with approximately twice the vertical and horizontal resolution of pre-existing television standards. It also provides audio quality approaching that of compact discs.
Incumbent Local Exchange Carrier (ILEC)
An ILEC provides telephone exchange services in a specific region. The regional boundaries for ILECs were determined by the Telecommunications Act of 1996.
Intercarrier payment
Expenses payable to another telecommunications service provider for a range of services, such as the transmission and termination of traffic, roaming charges, and services either for administrative purposes or to provide telecommunications services or facilities.
Interexchange carrier
A long distance company providing long-distance phone service between LATAs. Also called IEC and IXC.
Internet Service Provider (ISP)
Any service provider, including providers of voice telephony or cable television services that provides Internet connectivity or an Internet-based application on a retail or wholesale basis. ISPs may provide additional services, such as e-mail accounts and remote data file storage.
ISDN (Integrated Services Digital Network)
ISDN integrates speech and data on the same lines by providing access to packet switched networks over ordinary telephone copper wires. Prior to ISDN, phone lines were used overwhelmingly for voice, with limited data services.
LAN (local area network)
LAN is a transmission network encompassing a limited area, such as a single building or several buildings in close proximity. In such a small geographic area, leased telecommunication lines are not needed to link computers and devices.
Landline
Traditional wired phone service.
LATA (local access transport area)
A geographic service area established in accordance with the Modification of Final Judgment (MFJ) in order to define the area within which a telephone company may offer services.
LEC (local exchange carrier)
The local or regional telephone company that owns and operates lines to customer locations. It can be either an independent company or a Bell Operating Company.
Local loop
The communications channel, usually a physical line, between the customer’s premises and the edge of the telecom service provider’s network. It’s also known as a subscriber loop.
MMS (multimedia messaging service)
A wireless messaging service that adds images, text, audio clips, and video clips to SMS (Short Message Service/text messaging).
Mobile data
Mobile data is wireless data transmission to a handheld device, such as a smartphone or PDA. Mobile data plans have provided a growing source of revenue for telecom firms due to the popularity of smartphones.
Mobile penetration rate
Measures the number of mobile subscribers per 100 inhabitants and is usually represented as a percentage figure.
Modification of Final Judgment (MFJ)
The 1982 US federal court judgment that set the rules and regulations concerning deregulation and divestiture of AT&T and the Bell system.
Multiplexing
An electronic or optical process that combines a large number of lower-speed transmission lines into one high-speed line by splitting the total available bandwidth of the high-speed line into narrower bands (frequency division). The same result can be achieved by allotting a common channel to several different transmitting devices, one at a time in sequence (time division). Multiplexing devices are widely employed in networks to improve efficiency by concentrating traffic.
Network
Any system designed to provide one or more access paths for communications between users at different geographic locations. Networks may utilize circuit or message switching that route messages based on unique addresses for recipients.
OEM (original equipment manufacturer)
The manufacturer of products that are resold by another vendor who usually substitutes its name on the product for that of the manufacturer.
Packet
A group of binary digits switched over a digital network. When data has to be transmitted, it is broken down into similar structures of data, which are reassembled in the original data chunk when they reach their destination.
Packet switched network
A digital data transmission network that uses packet switching technology.
Packet switching
A digital data transmission method that divides messages and files into standard-size pieces (packets) that are switched across networks individually and then reassembled at their destination.
Prepaid calling card
A card or virtual card that is bought in advance entitling the owner to make phone calls. When the owner of the card makes phone calls, the value of the card decreases at a predetermined rate per minute.
Public Utilities Commission (PUC)
The agency regulating intrastate phone service.
RBOCs (regional Bell operating companies)
RBOCs resulted from the 1982 AT&T antitrust settlement with the US Department of Justice, in which it agreed to divest its local service companies. The seven resulting independent RBOCs are also known as the “Baby Bells.”
Reseller
A company that does not own transmission facilities. It purchases telecommunications services at wholesale and sells them to the public for profit. Also known as a Resale Carrier.
Roaming
A tariff charged by mobile communications network operators which allows a subscriber to use a cell phone outside of the local calling area. The tariff is usually measured by minute, data, or message. There are often at least two charges: an end-user retail charge paid by the end-user to a service provider, and an intercarrier retail charge paid from one service provider to another for network use.
Router
An electronic device that intercepts signals on a computer network. The router determines where the signals have to go. Each signal it receives is called a data packet, and the packet contains address information that the router uses to divert signals appropriately.
Satellite
A satellite communications system is composed of earth stations that communicate with each other via a radio relay station that orbits the earth—a satellite. Satellites are used to transmit a variety of data signals, including telephone and television.
Service area
An area within which a local phone company provides services. Also called a local access transport area (LATA).
Service plan
The rate plan you select when beginning wireless phone service. A service plan typically consists of a monthly base rate for access to the system and a fixed amount of minutes per month. Various service plans are offered to be cost-effective for different types of customers. Also called a rate plan.
Service provider
A telecom provider that owns circuit-switching equipment. In contrast, resellers provide phone services but don’t own the switching equipment. Also called a carrier.
SMS (short messaging service)
A wireless messaging service that permits the transmission of a short text message from and to a digital mobile telephone, regardless of whether the transmission originates and terminates on a mobile telephone. SMS messages can be up to 160 characters.
Spectrum
The range of electromagnetic radio frequencies used in the transmission of data, sound, and television.
Subscriber Line Charge (SLC)
A monthly fee paid by telephone subscribers that is used to compensate the local telephone company for part of the cost of installation and maintenance of the telephone wire, poles, and other facilities that link your home to the telephone network, aka the local loop.
Switch
A device that can be controlled to interconnect two circuits.
Telecommunications
As defined in the Telecommunications Act of 1996: the transmission between or among points specified by the user, of information of the user’s choosing, without change in the form or content of the information as sent and received. Any transmission, emission, or reception of signs, signals, writings, images, and sounds or intelligence by wire, radio, optical, or other electromagnetic systems.
Telephony
The technology of transmitting voice over distances via a telecommunications network.
Twisted pair
A cable consisting of two solid copper strands twisted around each other. The twisting provides a measure of protection from electromagnetic and radio-frequency interference.
Unbundling
Local exchange carriers providing other service providers access to buy or lease portions of their networks to serve subscribers.
Universal Service Fund Fee (USF)
Also known as Universal Service Fund Charge or Universal Service Charge. This charge started on January 1, 1998, as part of the FCC overhaul of telephone fees. The USF fee is a charge collected by telecommunications carriers for federal and state funds that support the provision of affordable communications services to rural, isolated, and high-cost regions of the country; low-income residential consumers; schools, libraries, and rural health care. Telecom companies are required by law to contribute to this fund, but the law does not prohibit companies from passing this charge on to customers.
VoIP (voice over internet protocol)
Any of a family of methodologies, communication protocols, and transmission technologies for delivery of voice communications and multimedia over Internet Protocol (IP) networks, such as the Internet.
WAN (wide area network)
A computer network that extends over a broad area. It usually connects LANs to other LANs using communications lines provided by a common carrier.
Wavelength
The distance between a point on one lightwave and the point of corresponding phase on the following lightwave. Lightwaves can be divided into wavelength portions and deployed as a series of communications channels. Although the bandwidth supplied by these channels is a function of the equipment deployed at their ends, most commercial wavelength products are offered in standard bandwidth increments, especially 2.5 Gbps and 10 Gbps.
Wi-Fi (802.11)
A limited-range wireless networking protocol based on the 802.11 family of standards, which enables a device such as a personal computer, video game console, smartphone, or digital audio player to connect to the Internet.