Broadband Glossary and Abbreviations

Broadband Glossary of Terms

4G – Abbreviation for fourth-generation wireless, the stage of broadband mobile communications that will supersede the third generation (3G). Specifies a mobile broadband standard offering both mobility and very high bandwidth. Usually refers to LTE and WiMax technology.

Access Network – Combination of Last and Second Mile portions of a broadband network. See Last Mile and Second Mile.

Actual Speed – Refers to the data throughput delivered between the network interface unit (NIU) located at the end-user’s premises and the service provider Internet gateway that is the shortest administrative distance from that NIU. In the future, the technical definition of “actual speed” should be crafted by the FCC, with input from consumer groups, industry and other technical experts, as is proposed in Chapter 4 of the National Broadband Plan. The technical definition should include precisely defined metrics to promote clarity and shared understanding among stakeholders. For example, “actual download speeds of at least 4 Mbps” may require certain achievable download speeds over a given time period. Acceptable quality of service should be defined by the FCC.

Asymmetric Digital Subscriber Line (ADSL) – A technology that transmits a data signal over twisted-pair copper, often over facilities deployed originally to provide voice telephony. Downstream rates are higher than upstream rates—i.e., are asymmetric. ADSL technology enables data transmission over existing copper wiring at data rates several hundred times faster than analog modems using an ANSI standard.

Broadband – According to the FCC, the term broadband commonly refers to Internet access that is always and faster than traditional dial-up access.  For the purposes of Utah’s broadband mapping and planning projects, the term broadband denotes high-speed Internet access equal to or above speeds of 768 kbps downstream and 200 kbps upstream.

Brownfield – A network in which a carrier already has infrastructure in the area that can be used to deliver service going forward.

Burst Rate – The maximum rate or “speed” which a network is capable of delivering within a short timeframe, typically seconds or minutes. This is usually expressed as a rate in Mbps.

CableCARD – A credit card-sized device that contains the video provider’s security information. When this card is plugged into a set-top box, it enables customers to access the video programming and services to which they have subscribed.

Capacity – Ability of telecommunications infrastructure to carry information. The measurement unit depends on the facility. A data line’s capacity might be measured in bits per second, while the capacity of a piece of equipment might be measured in numbers of ports.

Carrier of last resort – The carrier that commits (or is required by law) to provide service to any customer in a service area that requests it, even if serving that customer would not be economically viable at prevailing rates.

Census Block– The smallest level of geography designated by the U.S. Census Bureau, which may approximate actual city street blocks in urban areas. In rural districts, census blocks may span larger geographical areas to cover a more dispersed population.

Census tract – A small, relatively permanent statistical subdivision of a county, designed to contain roughly 1,000 to 8,000 people who are relatively homogeneous with respect to their demographics, economic status and living conditions.

Central Office (CO) – A telephone company facility in a locality to which subscriber home and business lines are connected on what is called a local loop. The central office has switching equipment that can switch calls locally or to long-distance carrier phone offices. In other countries, the term public exchange is often used.

Churn – The number of subscribers who leave a service provider over a given period of time, usually expressed as a percentage of total customers.

Code-Division Multiple Access (CDMA) – Any of several protocols used in so-called second-generation (2G) and third-generation (3G) wireless communications. As the term implies, CDMA is a form of multiplexing, which allows numerous signals to occupy a single transmission channel, optimizing the use of available bandwidth. The technology is used in ultra-high-frequency (UHF) cellular telephone systems in the 800-MHz and 1.9-GHz bands.

Commercial Mobile Alert System – A system established by the Federal Communications Commission that allows wireless service providers choosing to participate to send emergency alerts as text messages to their subscribers.

Commercial Mobile Radio Service – A mobile communications service that is provided for profit and makes interconnected service available to the public, usually in the form of mobile phone service.

Common carrier – A telecommunications provider, such as a telephone company, that offers its services for a fee to the public indiscriminately.

Competitive Access Provider (CAP) – Facilities-based competitive local exchange carriers (CLECs).

Competitive Local Exchange Carrier (CLEC) – The term and concept coined by the Telecommunications Act of 1996 for any new local phone company that was formed to compete with the ILEC (Incumbent Local Exchange Carrier). A company that offers local telephone service in competition with the legacy telephone company.

Coverage – In wireless communications, refers to the geographic area in which one can obtain service.

Customer Premises Equipment (CPE) – Equipment which resides on the customer’s premise. Examples include set top boxes , cable modems, wireless routers, optical network terminals, integrated access devices, etc.

Dark fiber – A fiber optic cable that is laid and ready for use, but for which the service provider has not provided modulating electronics; usually contrasted to lit fiber, which is fiber optic cable in use to provide wired communications.

Data Over Cable Service Interface Specification (DOCSIS) – A cable modem standard from the CableLabs research consortium (, which provides equipment certification for interoperability. DOCSIS supports IP traffic (Internet traffic) over digital cable TV channels, and most cable modems are DOCSIS compliant. Some cable companies are currently deploying third-generation (DOCSIS 3.0) equipment. Originally formed by four major cable operators and managed by Multimedia Cable Network System, the project was later turned over to CableLabs.

Digital signal 1 (DS-1) – Also known as T1; a T-carrier signaling scheme devised by Bell Labs. DS-1 is a widely used standard in telecommunications in North America and Japan to transmit voice and data between devices. DS-1 is the logical bit pattern used over a physical T1 line; however, the terms DS-1 and T1 are often used interchangeably. Carries approximately 1.544 Mbps.

Digital Subscriber Line (DSL) – A generic name for a group of enhanced speed digital services generally provided by telephone service providers. DSL services run on twisted-pair copper wires, which can carry both voice and data signals.

Digital Subscriber Line Access Multiplexer (DSLAM) – Technology that concentrates or aggregates traffic in DSL networks. Located in the central office or in a remote terminal.

Emergency Alert System (EAS) – A national public warning system that requires broadcasters, cable television systems, wireless cable systems, satellite digital audio radio service (SDARS) providers, and direct broadcast satellite (DBS) providers to provide the communications capability to the President to address the American public during a national emergency. The system also may be used by state and local authorities to deliver important emergency information, such as AMBER alerts and weather information targeted to specific areas.

Fast Ethernet (Fast-E) – A network transmission standard that provides a data rate of 100 Mbps.

Fiber to the Node (FTTN) – A high-capacity bandwidth approach that uses both fiber and copper wires. Optical fiber is used from the core of the telco or CATV network to an intelligent node in the neighborhood where copper wire is used for the connection to the end-user, with one node serving perhaps many residences or small businesses. The few 100 meters or so of the local loop from the node to the premises generally is either unshielded twisted pair (UTP) in a telco application or coaxial cable (coax) in an HFC application, although some form of wireless technology is also possible. Known as Fiber to the Neighborhood, or Fiber to the Cabinet (FTTCab), as well.

Fiber-to-the-Premise (FTTP) – A fiber-deployment architecture in which optical fiber extends all the way to the customer’s premise. Also known as Fiber to the Home (FTTH) or Fiber to the Building (FTTB). Typically using PON for residential deployments.

Fixed Wireless (FW) – Wireless service that uses fixed CPE in addition to (or, possibly, even instead of ) mobile portable devices to deliver data services. FW solutions have been deployed as a substitute for wired access technologies. For example, it is being used commercially in the U.S. by Clearwire with WiMAX and Stelera with HSPA, and globally by Telstra with HSPA.

Gateway device – A network device that acts as an entrance to another network and often is used to connect two otherwise incompatible networks.

Gigabit Ethernet (Gig-E) – A network transmission standard that provides a data rate of 1,000 megabits per second.

Greenfield – A network in which a carrier has no infrastructure currently (of that technology), and it needs to be built from scratch.

Housing Units (HU) – Includes a house, an apartment, a mobile home, a group of rooms or a single room that is occupied (or if vacant, is intended for occupancy) as separate living quarters.

Hybrid Fiber Microwave (HFM) – A network (usually wireless) whereby the backhaul transport elements of the network are a mixture or combination of fiber-optic facilities and wireless microwave transport.

Hybrid Fiber Coaxial (HFC) – Another term for cable systems, which are a combination of fiber (Middle and Second Mile) and coaxial cable (Last Mile).

Incumbent Local Exchange Carrier (ILEC) – The dominant local phone carrier within a geographical area. Section 252 of the Telecommunications Act of 1996 defines Incumbent Local Exchange Carrier as a carrier that, as of the date of enactment of the Act, provided local exchange service to a specific area; for example, Verizon, Windstream and Frontier. In contrast, Competitive Access Providers (CAPs) and competitive local exchange carriers (CLECs) are companies that compete against the ILECs in local service areas.

Independent System Operator (ISO) – An organization that coordinates, controls, and monitors the operation of the electrical power system, either within a single state or across multiple states.

Internet Gateway – The closest peering point between a broadband provider and the public Internet for a given consumer connection. See diagram below.

Internet Service Provider (ISP) – A company that provides a connection to the public Internet, often owning and operating the Last-Mile connection to end-user locations.

Last Mile – Refers generally to the transport and transmission of data communications from the demarcation point between the end user’s internal network and the carrier’s network at the customer premise to the first point of aggregation in the carrier’s network (such as a remote terminal, wireless tower location, or HFC node).

Long-Term Evolution (LTE) – A high performance air interface for cellular mobile communication systems. LTE technology increases the capacity and speed of wireless networks relative to current 3G deployments.

Loop – The connection from the network central office to t customers’ premises.

Microwave – Microwave transmission refers to the technique of transmitting information over microwave frequencies, using various integrated wireless technologies. Microwaves are short-wavelength, high-frequency signals that occupy the electromagnetic spectrum 1 GHz to roughly 300 GHz, (typically within ITU Radio Band Signal EHF) though definitions vary. This is above the radio frequency range and below the infrared range.

Microcell – Cell sites with extremely limited, but targeted, coverage. Microcells may provide indoor coverage in skyscrapers or may be placed in fire trucks, police cars and ambulances.

Middle Mile – Refers generally to the transport and transmission of data communications from the central office, cable headend or wireless switching station to an Internet point of presence.

National Broadband Availability Target – The level of service set in the National Broadband Plan that should be available to every household and business location in the U.S. The initial target is an actual download speed of at least 4 Mbps and an upload speed of at least 1 Mbps, with a proposed review and update every four years.

Next Generation 911 (NG911) – An emergency response system that integrates the core functionalities of the E911 system and also supports multimedia communications (such as texting, e-mail, and video) to the PSAP and to emergency personnel on the ground.

Node – An active or passive element in a cable system where Second-Mile fiber connects with coaxial cable.

Node splitting – In a cable system, adding infrastructure so that subscribers previously served by a single node are moved to multiple nodes, reducing the number of subscribers per node.

Offload – Shifting telecommunications traffic from one network to another to relieve network congestion.

Open source – A software development model by which the source code to a computer program is made available publicly under a license that gives users the right to modify and redistribute the program.

Over-builder – A facilities-based provider of cable service, telecommunications, or broadband that builds in an area already served by another facilities-based provider.

Overlay auction – An auction for licenses to unused portions of the spectrum already assigned to incumbent users.

Passive Optical Network (PON) – A type of Fiber To The Premise (FTTP) network in which unpowered optical splitters are utilized to enable a single fiber to be shared by multiple end users. There are several varieties of PON currently in use in the U.S., including BPON, EPON and GPON, each of which has its own set of standards and capabilities.

Plain Old Telephone Service (POTS) – The basic single line switched access service offered by local exchange carriers to residential and business end users, using loop-start signaling.

Point of Presence (POP) – An access point to the Internet. A point of presence is a physical location that houses servers, routers, switches and aggregation equipment. A location where a communications carrier allows other carriers to access its network.

Point to point (P2P) – A type of fiber to the premise network in which each endpoint is connected to its serving office via a dedicated fiber optic strand.

Public Safety Answering Point (PSAP) – A call center responsible for answering emergency calls and dispatching emergency services.

Public Switched Telephone Network (PSTN) – The worldwide collection of interconnected public telephone networks that was designed primarily for voice traffic. The PSTN is a circuit switched network, in which a dedicated circuit (also referred to as a channel) is established for the duration of a transmission, such as a telephone call. This contrasts with packet switching networks, in which messages are divided into small segments called packets and each packet is sent individually. Packet switching networks were initially designed primarily for data traffic.

Regional Bell Operation Company (RBOC) – Local exchange carriers formed after the breakup of AT&T in 1984. The seven regional holding companies (RHCs) of roughly equal size were formed as a result of the 1982 Consent Decree AT&T signed with the U.S. Department of Justice, stipulating that it would divest itself of its 22 wholly owned telephone operating companies. The seven RHCs were Ameritech, Bell Atlantic, BellSouth, NYNEX, Pacific Telesis, Southwestern Bell and US West. After a series of acquisitions, mergers and name changes (including one in which a combination of several RHCs reclaimed the original AT&T name), only three of the original seven remain. They are AT&T, Qwest and Verizon. The RBOCs are the incumbent local exchange carriers (ILECs) in their local markets.

Remote Terminal – Telephone communications equipment that is installed within the service area or “neighborhood” that traditionally aggregates and multiplexes telephone local loops and transmits the aggregated signals from the service area back to the telephone central office switch. This has evolved to become the “Node” within a service area in a fiber-to-the-node architecture.

Right-of-Way – The right to pass over or occupy a particular piece of land. For example, utilities generally receive right of-way from municipalities to erect and wire poles to carry electricity, telecommunications services, and cable service.

Second Mile – Refers generally to the transport and transmission of data communications from the first point of aggregation (such as a remote terminal, wireless tower location, or HFC node) to the point of connection with the Middle Mile transport.

Set-Top Box – A stand-alone device that receives and decodes programming so that it may be displayed on a television. Set top boxes may be used to receive broadcast, cable, and satellite programming.

Smart Grid – The electric delivery network, from electrical generation to end-use customer, integrated with sensors, software, and two-way communications technologies to improve grid reliability, security, and efficiency.

Smart Meter – A digital meter (typically electric) located on the customer premises that records energy usage and has two-way communications capabilities with utility systems.

Spectrum Allocation – The amount of spectrum dedicated (or allocated) to a specific use; in wireless, spectrum allocation is typically made in paired bands, with one band for upstream and the other for downstream.

Spectrum Band – The frequency of the carrier wave in wireless communications. Radios can transmit on different frequencies in the same area at the same time without interfering; frequency marks the division of different parts of spectrum for different uses. Frequency is measured in Hertz (Hz); the range of frequency typically used for radio communications is between 10,000 (10 kHz) and 30,000,000,000 Hz (30 GHz). Different frequencies have different natural properties: Lower frequencies travel farther and penetrate solids better, while higher frequencies can carry more information (faster data rates, etc.) The best balance of these properties for the purpose of cell phones is in the range of roughly 700-2,500 MHz. A specific range of frequencies allocated for a specific purpose is called a “band.”

Take Rate – The ratio of the number of premises that elect to take a service divided by the total number of premises in a market area; effectively a penetration rate of homes passed.

Teletype or Telephone Typewriter – A type of machine that allows people with hearing or speech disabilities to communicate over the phone using a keyboard and a viewing screen.

Time Division Multiple Access (TDMA) – Technology used in digital cellular telephone communication that divides each cellular channel into three time slots in order to increase the amount of data that can be carried. TDMA is used by Digital-American Mobile Phone Service (D-AMPS), Global System for Mobile communications (GSM), and Personal Digital Cellular (PDC). Each of these systems implements TDMA in somewhat different and potentially incompatible ways. An alternative multiplexing scheme to FDMA with TDMA is CDMA (code division multiple access), which takes the entire allocated frequency range for a given service and multiplexes information for all users across the spectrum range at the same time.

Unserved – Those housing units without access to a broadband network capable of offering service that meets the National Broadband Availability Target.

Very high bit rate Digital Subscriber Line (VDSL) – A form of DSL similar to ADSL but providing higher speeds at shorter loop lengths.

Voice Over Internet Protocol (VOIP) – A family of transmission technologies for delivery of voice communications over IP networks such as the Internet or other packet-switched networks. Other terms frequently encountered and synonymous with VoIP are IP telephony, Internet telephony, voice over broadband (VoBB), broadband telephony and broadband phone.

Wireless ISP (WISP) – An Internet service provider that provides fixed or mobile wireless services to its customers. Using Wi-Fi or proprietary wireless methods, WISPs provide last mile access, often in rural areas and areas in and around smaller cities and towns. The largest provider of wireless broadband in the U.S. is currently Clearwire Corporation, a WISP that uses an early version of WiMAX to deliver the Internet to customers in the U.S., Ireland, Belgium and Denmark (see WiMAX).

Wireless Priority Service (WPS) – A federal program that authorizes cellular communications service providers to prioritize calls over wireless networks. Participating service providers typically deploy WPS in stages until service is available in most coverage areas and functionality has reached full operating capability.

WiMax – Worldwide Interoperability for Microwave Access (WiMAX) is a telecommunications technology that uses radio spectrum to transmit bandwidth between digital devices. Similar to WiFi, WiMAX brings with it the ability to transmit over far greater distances and to handle much more data.

Common Abbreviations

3G                    Third generation
4G                    Fourth generation
ADSL              Asymmetric Digital Subscriber Line
AGRC              Automated Geographic Reference Center (State of Utah)
AMPS              Advanced Mobile Phone Service
BDIA               Broadband Data Improvement Act
BIP                  Broadband Infrastructure Program
BPON              Broadband Passive Optical Network
BTOP              Broadband Technology Opportunities Program
CAP                 Competitive Access Provider
CDMA             Code-Division Multiple Access
CLEC               Competitive Local Exchange Carrier
CO                   Central Office
CPE                 Customer Premises Equipment
DOCSIS           Data Over Cable Service Interface Specification
DS1                  Digital Signal 1
DS3                  Digital Signal 3
DSL                 Digital Subscriber Line
DSLAM           Digital Subscriber Line Access Multiplexer
DTS                 Department of Technology Services (State of Utah)
DTV                Digital television
E911                 Enhanced 911
EAS                 Emergency Alert System
EPON              Ethernet Passive Optical Network
ERIC                Emergency Response Interoperability Center
EV-DO            Evolution-Data Optimized
FCC                 Federal Communications Commission
FS-ISAC          Financial Services Information Sharing and Analysis Center
FTTN               Fiber to the Node or Fiber to the Neighborhood
FTTP               Fiber-to-the-Premise
FW                   Fixed Wireless
Gbps                 Gigabits per second
GHz                 Gigahertz (1 billion Hertz)
GIS                  Geographic Information System
GOED             Governor’s Office of Economic Development (State of Utah)
GPS                 Global Positioning System
GSM                Global System for Mobile communication
HD                   High definition
HFC                 Hybrid Fiber Coaxial
HFM                Hybrid Fiber Microwave
HU                   Housing Units
Hz                    Hertz
ILEC                Incumbent local exchange carrier
IP                     Internet Protocol
IPAWS            Integrated Public Alert and Warning System
ISAC                Information Sharing and Analysis Center
ISO                  Independent System Operator (ISO)
ISP                   Internet service provider
IT                     Information technology
IT-ISAC           Information Technology Information Sharing and Analysis Center
IXC                  Interexchange Carrier
kbps                 Kilobits per second
Kft                   Kilo-feet (1,000 feet)
kHz                  Kilohertz (1 thousand Hertz)
kWh                 Kilowatt-hour LATA Local Access and Transport Area
LEC                 Local exchange carrier
LTE                 Long-Term Evolution
Mbps                Megabits per second (1 million bits per second)
MHz                 Megahertz (1 million Hertz)
MSA                Metropolitan service area
MS-ISAC         Multi-State Information Sharing and Analysis Center
NBP                 National Broadband Plan
NG911              Next Generation 911
NIST                National Institute of Standards and Technology
NTIA               National Telecommunications and Information Administration
PBS                 Public Broadcasting Service
PC                   Personal computer
PDF                 Portable Document Format
POP                 Point of Presence
PON                Passive Optical Network
POTS               Plain Old Telephone Service
PSAP               Public safety answering point
PSBL               Public Safety Broadband Licensee
PSC                 Public Service Commission (State of Utah)
PSTN               Public Switched Telephone Network
QOS                 Quality of Service
R&D                Research and development
RBOC              Regional Bell Operation Company
RSA                 Rural service area
RUS                 Rural Utilities Service
SIM                  Subscriber Identity Module
SLC                 Subscriber line charge
SMS                 Short Message Service
TDMA             Time Division Multiple Access
Telco                Telecommunications
TOP                 Technology Opportunity Program
TV                   Television
UHF                 Ultra high frequency
USF                 Universal Service Fund
VDSL              Very high bit rate Digital Subscriber Line
VHF                 Very high frequency
VOIP               Voice Over Internet Protocol
WCS                Wireless Communications Service
WiMAX           Worldwide Interoperability for Microwave Access
WISP               Wireless Internet service provider
WPS                Wireless Priority Service

Glossary and Common Abbreviations Sources: