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Montana's State Broadband Website

Montana's State Broadband Website

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Montana Broadband

Connecting Across the Big Sky

Montana Broadband

Connecting Across the Big Sky

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Broadband Terms 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

A

A/D (Analog-to-Digital Converter): A device that constantly converts varying analog signals to digital signals.

Access Channels: Channels set aside by a cable operator for use by third parties, including the public, educational institutions, local governments, and commercial interests unaffiliated with the operator (see also PEG and LEASED ACCESS).

Access: The service provided by local exchange carriers or alternate access providers, that enable a user to enter a circuit and connect with an interexchange carrier.

ADSL (Asymmetrical Digital Subscriber Line): A modem technology that provides greater bandwidth from ordinary telephone lines. Asymmetrical is able to provide faster one way speed connectivity between the central office and the customer premises.

American Recovery and Reinvestment Act (ARRA): The American Recovery and Reinvestment Act was passed by Congress in 2009.

Analog: A mechanism or method in which data is represented by continuous variable physical quantities and that uses nondiscrete variations in frequency, amplitude or location to carry sounds, signals, mathematical data or other information.

Aspect Ratio: The ratio of a television screen?s width to its height (4:3 for NTSC, 16:9 for HDTV).

ATM (Asynchronous Transfer Mode): A high-speed multiplexing and switching technique that uses fixed size of cells to support several types of traffic such as voice, data and video.

ATV (Advanced Television): A series of digital television technologies that are designed to improve the current commercial-quality television system.

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B

Bandwidth (BW): A measure of the capacity of a channel of communications in the broadcast spectrum. A range of frequencies or the amount of spectrum used to transmit pictures, sound, and data (In the United States, the Federal Communications Commission has assigned broadcast television channels a bandwidth of 6 megahertz).

Base Station(BS): A fixed land station in the land mobile service that relays signals to and from mobile voice and data terminals or handsets.

Basic Cable: Primary level or levels of cable service offered for subscription. Basic cable offerings may include retransmitted broadcast signals as well as local and access programming. In addition, regional and national cable network programming may be provided. Basic service offerings at the system level may be offered as more than one tier.

BPS (Bits Per Second): Transmission rate for digital information expressed as the number of bits (zeroes or ones) sent or received per second. Broadband Communications System: A network such as a cable system capable of delivering multiple high capacity services simultaneously.

Bundling: Combining goods and/or services into a single package, often for a discounted price.

Business Support System(BSS): A system that supports and manages information of various telecommunication functions such as billing, data warehousing, customer care, network management and account receivables.

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C

Cable Modem: A communication device connected to a personal computer which offers customers access to the Internet over a cable system at speeds 50-100 times faster than a telephone connection. Cable Ready: Label for consumer electronic devices, such as television sets and VCRs, that are designed to allow direct connection to a cable television network.

Cable System: A localized communications network that distributes television, Internet, and telephone services by means of coaxial cables and/or fiber optics.

Cablecasting: The use of cable systems by federal, state, and local officials

CATV (Community Antenna TV): Also known as Cable TV, it uses several TV units connected by cable to a common antenna to serve a community.

CBR (Continuous Bit Rate): A transmission rate that is uniform.

CCITT (Consultative Committee International Telephony and Telegraphy): Presently known as the International Telecommunications Union (ITU), the ITU sets and develops standards for telecommunications.

CDPD (Cellular Digital Packet Data): Developed by IBM as a way to transmit short wireless data messages, such as credit card verification, over cellular providers' analog network.

Central Office: A telecommunications facility (generally serving 10,000 telephone lines) where local calls are switched.

Channel Capacity: Maximum number of television channels that a cable system can carry simultaneously.

Coaxial Cable (Coax): A transmission line 1/4 to 1 inch thick with an inner wire to conduct signals and an outer aluminum coating to act as a ground. The two metal layers are separated by insulation and may be wrapped in a protective plastic sheathing.

CODEC (Coder/Decoder): A device that converts digital codes to analog and vice versa.

Committed Information Rate: The bandwidth committed by the carrier for the port connection that is assigned to a permanent virtual circuit in a frame relay network.

Common Carrier: A communications provider, such as a telephone company, which offers its services to all members of the public for a set fee (tariff). Common carriers are regulated by federal and state agencies and exercise no control over the content of the messages they carry.

Community Antenna Relay Service (CARS): Microwave facilities used to relay television, FM radio, and other signals from a cable television headend to a reception site for distribution over cable.

Competitive Access Provider (CAP): Companies that provide connections to long distance providers while bypassing local telephone companies.

Compression: A technique for reducing the number of bits that make up a digital television signal and reducing the amount of bandwidth required to carry it. By reducing the bandwidth necessary to carry compressed digital signals, cable companies and others can greatly increase the number of channels they offer to consumers.

Converter: Device which increases the number of channels that a TV set can receive by converting the large number of signals carried on a cable or satellite system to a single channel tuned by the TV set, e.g., channel 3 or 4.

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D

dial-up: a temporary internet connection made by 'dialing' a telephone number from a computer

Digital Cable: Cable services, programming, and equipment that use digital, not analog, formats (see DTV and HDTV).

Digital Crossconnect System (DCS): A high-speed data channel switch that in response to dialing instructions independent of the data traveling through, switches transmission paths.

Digital Data Service (DDS): A synchronized digital service that interconnects digital transmission centers.

Digital Selective Calling (DSC): A synchronous system that is used to set up contact by radio with a station or group of stations.

Digital Signal Level 0 (DS-O): A classification of digital circuits with a rate of transmission rate of 64 kb/s.

Digital Signal Level 1 (DS-1): The rate of transmission of a DS-1 (or T -1) is of 1 .544 Mb/s and 24 channels are associated with it.

Digital Signal Level 3 (DS-3): The rate of transmission of a DS-3 (or T -3) is of 44.736 Mb/s and is associated with 672 channels.

Digital Signal Processor (DSP): A special programmable device used for digital signal processing by providing ultra-fast instruction sequences.

Digital: An intelligence-carrying signal consisting of a stream of bits of zeros and ones for sound, video, computer data or other information.

Direct Broadcast Satellite (DBS): A TV broadcast service from a small satellite dish antenna that offers similar services, like that of cable TV, and which transmits highly compressed digital signals.

Dish: A parabolic antenna used to receive satellite transmissions at home. The older 'C band' dishes measure 7-12 feet in diameter, while the newer 'Ku band' dishes used to receive high- powered DBS services can be as small as 18 inches in diameter.

Distant Signal: Television signal from another city that is imported and carried locally by a cable television system.

Downstream: Flow of signals from a cable system?s headend through its distribution network to a customer.

Drop Cable: The final stretch of coaxial cable that connects a customer?s home to the cable system.

DSL: A Digital Subscriber Line provides Internet access over the wires of a telephone, allowing data transmission simultaneously with voice.

DTH (Direct-To-Home): All satellite service providers, including C-band and Ku band (DBS).

DTV (Digital TV): Television signals transmitted and received in digital format (discontinuous zeroes and ones; compare with ANALOG). Digital TV has several formats and varying degrees of resolution, from 480 lines per screen progressively scanned to 1080 lines interlaced. DTV includes HDTV, but not all DTV is HDTV since the bandwidth required for HDTV can be broken down to accommodate several DTV signals of lesser resolution.

Dual Cable: Two wires or coaxial cables operating side-by-side to provide extra channel capacity and interactivity.

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E

Earth Station (ES): A satellite communications center, including the antenna, receiver and electronics necessary in receiving satellite transmitted signals.

Electronic Data Interchange(EDI): An electronic messaging system for the trading and interchanging of information.

Ethernet : The Institute of Electrical and Electronic Engineers' (IEEE) widely used access method for the local area network (LAN) protocol. An 'ethernet' connection is often distinguished from 'wireless' as a network connection using a cable.

Extranet: The part of a company or an organization internal computer network which outside users and which uses the public Internet as its transmission system, but requires passwords to gain access.

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F

FDDI-LAN (Fiber Distributed Data Interface- LAN): An American National Standards Institute (ANSI) and ISO defined standard for high-speed (100 MBPS) local area network (LAN) communications using fiber-optic cable as the transmission medium.

Federal Communications Commission (FCC): Established by the Communications Act of 1934, the FCC is the federal agency in charge of overseeing interstate telecommunications, as well as all the communications services originating and terminating in the United States.

Feeder Line: Intermediate distribution line (fiber or coaxial cable) that connects a trunk from the headend to the drop cables serving individual homes.

Fiber Distributed Data Interface (FDDI): An ANSI define standard by which computers can communicate at 100 million bits per second over fiber-optic token ring network.

Fiber Optics: Thin transparent fibers of glass or plastic that are enclosed by material of a lower index of refraction and in which Light-Emitting Diodes (LED)s send light through the fiber to a detector that turns the light into an electrical signal.

Fiber: Refering to fiber-optic cable, of which there are several 'grades', all used in high-speed transmission of data.

Forbearance: A regulatory body?s decision not to exercise its authority over a given market or company, usually because there is competition.

Forward Error Correction (FEC): A data transmission technique that is able to correct for bad data transmitted on the receiving end by using the correction bits and a predetermined algorithm sequence.

Frame Relay (FR): A packet access protocol primarily used to interconnect distant LANs and routers together, to Internet access via T -1.

Franchise: Contractual agreement between a cable operator and a governmental agency

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G

Gateway Server (GS): A station on the local area network that has devices necessary to provide system interoperability between one or more network users.

GIS: Geographic Information System data is commonly map data in digital format, which enhances visualization and interpretation of maps and map 'dimensions.'

GSM (Global Standard for Mobile Telecommunications): A TDMA standard set by the European Union for all European countries and increasingly used throughout the world, for two- way digital cellular systems. It operates in the 1.8 to 1.9 GHz band in North America.

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H

H.323 : An ITU standard for videoconferencing over packet-switched network which is widely supported for Internet telephony.

Hardware : Equipment involved in the production, storage, distribution, and reception of electronic signals, such as computers, amplifiers, cameras, and VCRs.

HDSL (High Data Rate DSL): A digital subscriber line technology that allows for upstream data transmission at T -1 of fractional T -1 speeds and quality over copper wires.

HDTV (High Definition Television) : Digital television which offers twice the resolution, wider screens, better sound, and better color than the NTSC format. ?True? HDTV involves a 16:9 aspect ratio and at least 720 lines per screen.

Headend : Facility that originates and distributes cable service in a given geographic area. Depending on the size of the area it serves, a cable system may be comprised of more than one headend.

HFC (Hybrid Fiber/Coax) : A network architecture developed by the cable industry which uses a blend of fiber and coaxial cable to bring consumers interactivity, greater channel capacity, increased signal strength, and improved reliability.

Homes Passed : Households with the ability receive cable service and which may opt (not) to subscribe.

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I

Independent: Name given to an individually owned and operated cable television system (compare with MSO).

Institutional Network (I-NET): A private, dedicated network built and/or operated by a cable TV system for local schools, businesses, or government.

Interactive: Two-way communications allowing a person to both send and receive information (compare with passive or receive-only systems, such as broadcast television).

Interconnection: The linking of two or more telecommunications networks, such as a cable system to a local exchange company or a long distance carrier.

Interlaced: A scanning format for televisions which blends two separate images, alternatively scanned on odd and even numbered lines, into one frame (compare with PROGRESSIVE scanning).

International Telecommunications Union (ITU): An international organization within which governments and private sectors set communications standards.

Internet Service Provider (ISP): A service provider that has its own network (or leases) to which end-users dial into to connect to the Internet.

Internet Telephony Service Provider (ITSP): A company that provides users with telephony service via the Internet through standard telephone wires.

Internet : A global data network supporting research, engineering, commercial, information, and educational services.

Intranet : An in-house company network Web site that serves the employees of the enterprise and which offers similar features and services as the Internet.

IP (Internet Protocol): An International Standards Organization (ISO) standard that implements the network layer 3 of an open system interconnection (OSI) model that contains a network address and is utilized in directing a message to a different network.

IS (Information Service): The name given the department in a company which oversees the computers, networking and data management. This term has been updated to IT (Information Technology).

ISDN (Integrated Services Digital Network) : A standard and integrated digital network that allows users to simultaneously send voice, data and video over multiple multiplexed communications channels from a common network interface.

ISN (Internet Service Node) : An interconnection point in the Internet network to other specific entities.

IXC (Interexchange Carrier): A long distance telephone company linking separate local exchanges.

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L

Layer-1 : Networking: the fist phase of the communications protocol of the open system interconnection (OSI) model, also referred to as the physical layer, which provides the transmission of bits over the network medium.

Layer-2 : Networking: the second layer of the open system interconnection (OSI) model that contains the physical address of a client or server station, also called the data link layer.

Layer-3 : Networking: the third layer of the open system interconnection (OSI) model, which contains the logical address of a client or server station.

Layer-4 : Networking: also known as the transport layer, it is the layer of the open system interconnection (OSI) model which provides end-to-end management of the communications session.

Layer-5 : Networking: the fifth layer of the open system interconnection (OSI) model that initiates and manages the communications session.

Leased Access : Commercial channels made available by a cable operator to third parties for a fee, as required by the Cable Acts of 1984 and 1992.

Liquid Crystal Display (LCD): An electro-optical display technology that uses rod-shape molecules that flow like liquid and bend light.

Local Area Network (LAN): A data communications network that links together computers and peripherals to serve users within a confined area.

Local Exchange Carrier (LEC): Any authorized carrier that has been given permission by the state PUC to provide local voice-level telecommunications services within a predetermined area

Local Multipoint Distribution Service (LMDS): A wireless cable system that enables greater upstream bandwidth than most other wireless services from a fixed station for entertainment video and CLEC services.

Local Origination Programming (LO): Material developed by an individual cable television system specifically for the community it serves.

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M

Main Distribution Frame (MDF): A unit that connects between outside plant cables and internal lines or line equipment in the central office (CO).

Metro Area Exchange (MAE): Major access points in a network in the Internet.

Metropolitan Area Network (MAN): A communications network that covers a large portion of a city or a large campus through which two or more LANs interconnect.

MMDS (Multi-Channel/Multi-Point Distribution System) : A wireless cable service using microwaves to transmit multiple television signals to customers.

MODEM (Modulator?Demodulator): An electronic device that allows users to connect computers and other equipment in their homes, schools, or businesses to a network for the purpose of sending and/or receiving data.

MPEG (Moving Picture Experts Group): An international group that sets standards for compressing video images.

Multiplexer (MUX): A device that combines many input devices into one compiled signal to be carried over one telephone line.

Multipoint Distribution Service (MDS): A pay-TV broadcast delivery service through microwave frequencies from a fixed station to multiple small dish antennas.

Must Carry: A policy, developed by the FCC in the 1960s and codified by Congress in 1992, requiring cable systems to carry the analog signal of a local television station if that broadcaster so chooses (see also RETRANSMISSION CONSENT). The Supreme Court voted 5-4 in 1997 to uphold must carry for analog broadcast television signals.

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N

National Telecommunications and Information Administration (NTIA): The National Telecommunications and Information Administration is part of the Department of Commerce, and is principally responsible for advising the President on telecommunications and information policy issues.

National Television System Committee (NTSC): Responsible for the specifications administered by the FCC for commercial broadcasting.

Near Video On Demand: The practice of offering the same programming on different channels at different times so that customers do not have to wait long for a desired show to begin.

Network Access Point (NAP): Also known as the Internet Exchanges (IXS), it is a point where major Internet service providers come together and interconnect with each other.

Network Element Layer (NEL): The layer of an integrated digital network whose function and capabilities include the information necessary for billing and collection, for routing or transmission of a telecommunications service.

Network Interface Card (NIC): An interface card that interconnects all the adapters in a computer to provide access to the network.

Network Service Provider (NSP): An Internet provider that offers high-speed backbone services.

Node: A connection point in a cable system (often where a fiber enters a neighborhood and connects to coaxial cables serving 200-1000 individual homes).

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O

Off-The-Air: Refers to the reception of broadcast television signals with a local antenna (either roof-top or set-top) instead of through a cable or satellite dish.

OpenCable : An initiative of the cable industry (through CableLabs) to develop and label a new generation of interoperable digital boxes available through retail stores that will provide subscribers with video, data, and interactive services.

Open System Interconnection (OSI) : A logical structure developed by the International Standards Organization to enable devices from multiple vendors to communicate with any other OSI-compliant system.

OSP (On-Line Service Provider) : An interactive computer service such as Road Runner, @Home, or AOL which provides subscribers with proprietary information as well as access to the Internet (compare with ISP).

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P

Packet Transfer Mode (PTM): A technique of packet switching and transmission that enables more effective sharing of network resources by various users.

Packet: A group of bits switched as a unit block of data used for transmission in a packet-switched network.

Pay Cable Unit: Each premium service to which a household subscribes is counted as one unit. Pay-Per-View: Pay service that enables a subscriber to order and view events or movies on anindividual basis.

Pay Cable: A network or service available for an added monthly fee. Also called premium. Some services, call mini-pay, are marketed at an average monthly rate below that of full-priced premium.

PEG (Public, Educational, and Governmental): See ACCESS CHANNELS.

Penetration: The number of homes actually served by cable in a given area, expressed as a percentage of 'homes passed' (e.g. cable penetration in November 1998 was 67.4 percent nationwide).

Permanent Virtual Connection (PVC): A point-to-point virtual connection scheduled ahead of time for a long-term connection between data terminal equipment.

Plant: Number of cable plant miles laid or strung by a cable system; the cable miles in place.

Point of Presence (POP): A site where telecommunications companies (such as cellular and long distance (IXC) providers) physically interconnect their systems with other networks (such as local telephone companies or cable companies).

Point-to Point Protocol (PPP): A data link protocol that is popular for Internet access and for carrying higher level protocols, while supporting both asynchronous and synchronous lines.

Pole Attachment: The place where, for a fee, cable systems attach their wires to telephone or utility poles.

Premium Services : Individual channels such as HBO and SHOWTIME which are available to cable customers for a monthly subscription fee.

Primary Rate Interface (PRI): An interface standard for integrated services digital network providing a total of 1.544 MBPS.

Public Service Commission (PSC): Also known as the Public Utilities Commission (PUC), a state regulatory body that oversees public utility service providers.

Public Switched Telecom Network (PSTN): The common domestic telecommunications network that is access by private branch exchange trunks, telephones, and Centrex systems.

Public Utility Commission (PUC): A state regulatory body that is responsible for establishing and implementing public policy and regulating intrastate utilities.

Pulse Code Modulation (PCM): The sampling of a signal and each sample is then digitized so as to have it transmitted over a medium.

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R

Radio Frequency (RF): The range on the electromagnetic frequencies with radio transmission. (RJ-11 Jack) Registered Jack -11: The type of phone jack that local telephone companies wire for most residential homes and which can only hold one line.

RADSL (Rate Adaptive DSL): A modem technology (DSL) that maximizes the digital speed of copper lines and adjusts speeds in reference to signal quality.

Real Time Protocol (RTP): An Internet protocol for the transmission of voice and video.

Regional Hubs : Fiber optic rings that link several adjacent or regional headends, thus improving reliability, lowering costs, and expanding cable?s offerings to include Internet access and telephone service.

Resource Reservation Protocol (RSVP) : A network protocol that signals a router to reserve a resource along the data path for real-time transmission.

Retransmission Consent : A policy enacted by Congress in 1992 requiring cable operators to secure the consent of local television stations before retransmitting their signals. Instead of retransmission consent, broadcasters may choose MUST CARRY.

Router : A device that forwards data packets of a specific protocol type from one logical network to another logical network, based on routing tables and routing protocols.

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S

Satellite : Communications device usually located in geostationary orbit, which receives transmissions from earth and retransmits them to different parts of the globe.

Scrambling : An electronic security technique used to render a TV signal unviewable unless it is processed and restored by an authorized decoder or descrambler.

SHVA (Satellite Home Viewer Act) : Federal law (section 119 of the Copyright Act) which gives direct-to-home satellite distributors such as DBS a compulsory license for the retransmission of broadcast television programming. The SHVA will expire on December 31, 1999, unless extended by Congress.

Signaling : The transmission of electrical signals that contain switching information between stations, user's premises, offices and various central offices.

SLIP (Serial Line Internet Protocol) : A protocol that enables a computer to utilize Internet Protocol via high-speed modem and a telephone line.

Speed Data: Information about a user's Internet connectivity collected from a 'speed test' It is used to help build and verify broadband maps, using information such as your Internet transmission speed, provider, IP address, and geographic location.

Subscriber : This term is used interchangeably with household.

Switched Multimegabit Data Service (SMDS) : A fast packet-switching service offered by local telephone companies to provide cross-premises communications services between LANs.

Synchronous Optical Network (SONET) : An American National Standards Institute (ANSI) standard for high speed, fiber optical transmission on the network.

Synchronous Transport Signal (STS): The signal rate carried over a Synchronous Optical Network (SONET).

System : Facility that provides cable service in a given geographic area, comprised of one or more headends.

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T

T-1 : Two pairs of copper wire that can carry 24 DS-O signals at a rate of 1.544 MBPS. (TA)

TCP/IP (Transmission Control Protocol/Internet Protocol) : A communications protocol developed by the Department of Defense to inter-network dissimilar systems and operates at layers 3 and 4 (network and transport, respectively) of the OSI model.

Telecommunications Management Network (TMN) : A network using a set of international standards that interconnects and interfaces with a telecommunications network in order to interchange information in order to control and maintain the telecommunications network.

Teleradiology : A system that enables the viewing and processing of images within a hospital's nuclear medicine departments or remote image viewing from home computers or remote sites.

TELNET Virtual Terminal Protocol : An Internet service that allows a user to create an interactive session with a computer on a different network as if they were actually on that system.

Terminal Adapter : An external device, which connects computers to an ISDN line.

Tier : A package of television channels offered to customers for a single price. Most cable systems have more than one tier, e.g., a basic package including local broadcast stations, and one or more expanded tiers featuring popular cable program networks. In addition, cable operators offer premium subscription services, such as HBO and SHOWTIME, and pay-per-view events such as movies, boxing matches, and concerts.

Time Division Multiplexing (TDM) : A digital multiplexing method to merge signals from two or more channels, such as telephones, computers, and video, into a common channel for transmission over telephone lines.

Translator : A relay system that picks up distant television signals, converts the signals to another channel to avoid interference, and retransmits them into areas the original television station could not reach.

Transponder : The part of a satellite that receives and retransmits a signal.

Transport : The transfer access service to and from a point of presence (POP) serving wire center and a customer's serving wire center or 'end office' (EO).

Trunk : A communications network that can be used to connect circuits between switches or to interconnect switches themselves to form a network.

Trunking : Transporting signals from one central point in a cable system (such as a headend) to another site without serving customers directly. Trunking can be accomplished by using fiber optics, coaxial cable, or microwave, although fiber is now the norm for the cable industry.

Two-Way : See INTERACTIVE.

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U

UDP (User Datagram Protocol) : A host-to-host protocol, which allows an application program on one computer to send a datagram to an application on another computer via packet-switched communications network.

Unbundling : Requiring local exchange companies to separate the various components of their telephone service into independently available and separately priced features, such as the local loop, switching, operator assistance, and billing.

Underground Installation : Installing coaxial and fiber cable underground as opposed to hanging it from poles (compare with AERIAL PLANT).

Universal Service : A fund to which interstate carrier must contribute in order to provide access to the advanced interexchange telecommunications services to those people living in rural areas and where it world otherwise not be cost- efficient to invest.

Unserved Area : See WHITE AREA. Upstream: Flow of information from a customer back up through a cable system to the headend.

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V

Video On Demand : The ability to provide television programming to customers upon request (see also NEAR VIDEO ON DEMAND).

Virtual Private Network (VPN) : A private switched network that allows sites that are connected with one another to contact each other without dialing all eleven digits.

VPI/VCI (Virtual Path Identifier Virtual Channel Identifier) : The combination of the address of a virtual circuit and of a virtual path, thereby identifying a connection on an ATM network.

(VSAT) Very Small Aperture Terminal : A small earth station for satellite transmission and which is made up of one master earth station and several two- way satellite terminals. Commonly used by multinational firms in the transmission of fax, voice, and data throughout a widespread area.

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W

Wavelength Division Multiplexing (WDN) : A technology that utilizes the transmission of multiple light signals simultaneously through the same optical fiber, while preserving the integrity of each individual signal.

White Area : An area unserved by a local, over-the-air broadcast signal (outside its grade B contour).

Wide Area Network (WAN) : A network that connects two or more LANs in multiple cities via telephone lines.

Wi-Fi: A technology which allows an electronic device to connect to the internet wirelessly using radio waves.

World Wide Web (WWW) : A basic way of communication through the Internet for world- wide hypertext linking of multimedia documents.

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