TELECOMREG FAQS: DEFINITIONS AND ACRONYMS Edited by Barry Orton and John M. Higgins Sources: Wisconsin Governor's Blue Ribbon Telecommunications Infrastructure Task Force; Orange County, Florida "Cable Alphabet Soup;" Springfield (Mo.) Cable Television Franchise; Television & Cable Factbook. A/B Switch: Coaxial or high isolation switch used for selecting one of two input signals, E.G. switching between a cable line and a broadcast antenna. Access Channel: Dedicated channels giving non-discriminatory access to a cable system by the public, government agencies, or schools. Cable operators generally cannot dictate how an access channel is programmed; the channels are generally run by independent non-profit groups, schools or governments. See Section 61l of the Communications Act [47 U.S.C. (531)] ("Cable channels for public, educational, or government use"). Access Charge: Since the AT&T breakup, all telephone users pay local telcos for access to long distance networks. Also called "subscriber line charges." Long distance carriers pay a different set of access charges for a local telco to carry a long distance call to its recipient. Up to 45 percent of the retail cost of a long distance call goes to local telcos for access. Activated Return Capacity: The capability of transmitting signals from subscriber or user premises to the headend. Addressability: The capability of controlling the operation of individual cable subscriber set-top converters by sending commands from a central computer. Absolutely required for a system to offer pay-per-view services, convenient in turning subscribers to pay services on and off. ADI: Area of Dominant Influence. An advertising term delineating the reach of local media, primarily TV stations. The ADI is established by Arbitron ratings. The key determinant of whether a TV station has "must-carry" status on a particular cable system. Affiliate: A cable system that agrees to offer a particular programming service to its subscribers is an affiliate of that service; a television station carrying the programming of a broadcast network is an affiliate of the network. Alternate Access: aka competitive access. Telephone service bypassing the local telco to either link directly to a long-distance carrier or separate local phone net. Because long-distance access charges are so high, alternate access providers (alts) can undercut local telcos when routing traffic from a high-volume commercial user to ATT or MCI. Alts include Teleport and Metropolitan Fiber. Alts: Alternate Access providers. Amplifier: Device used to boost the operating level of an electronic signal. Used in a cable system's distribution plant to compensate for the effects of attenuation caused by coaxial cable and passive device losses. Analog: A way of sending voice, video or data signals in which the signal resembles the original, rather than being an exact copy like a digital signal. A continuously-varying electrical signal in the shape of a wave. From the word "analogous." ANI: Automatic Number Identification. Equipment that automatically records the calling number of an incoming telephone call, and also passes it along to other equipment so the call can be billed. Also called CLI or Calling Line Identification. Architecture: How a system is designed and how the components are connected and operate together. As-Built Maps: Maps depicting a cable system as it has been constructed. Asynchronous: The capability of communications to be time-independent because the information can be stored or recorded for later playback; or, communications that are only one way at a time. ATM: Asynchronous Transfer Mode or "Automated Teller Machine." Audiotex: A generic term for interactive voice response equipment and services for one-way (listen only) voice bulletin board systems and services. Automated Response System: Telephone answering system which routes callers through a voice-mail-like menu. Bandwidth: The potion of the radio spectrum needed to transmit pictures, sound or both. A video channel uses about 620Mhz of bandwidth, while a typical cable system has a bandwidth capacity of 300-550Mhz. Basic cable: The lowest tier of cable service available to a subscriber that includes over-the-air broadcast signals. Basic rates are regulatable by local franchise authorities upon certification by the FCC. Baseband: A signal in its original form, not changed by modulation. May be analog or digital. Bird: jargon for a satellite. Bit: One bit is one digital signal element; a single alphabetical or numeric character is typically represented by 10 bits. BITNET: "Because It's Time" Network, an electronic mail network connecting 300+ universities as well as major European and Asian academic data networks; see also Internet. BOC: Bell Operating Company. Also RBOCs or "Baby Bells." BPS: Bits per second. A measure of the amount of data transmitted in a fixed amount of time. Bridge: Communications device that passes information between two separate networks. Broadband: A transmission channel with a bandwidth greater than an ordinary voice channel. Cable: One or more electrical or optical conductors found within a protective sheathing. Capacity: A measurement of the maximum amount of signal which can be carried by a cable system. Caps: Competitive Access Providers. CARS: Cable Television Relay Station: A microwave system used to relay TV signals to a cable headend for delivery to subscribers. The signal of a distant broadcast TV signal may be relayed via microwave to a cable system. CATV: Community Antenna Television or Cable TV. The cable business started by erecting antenna towers to funnel broadcast signals to homes in valley whose reception was blocked by mountains, hence "community" antennas. CATV is a broadband service. CD-ROM: Compact Disk Read Only Memory. Higher capacity than conventional magnetic discs, but cannot be altered by the user. Cellular Service: A mobile radio service in which an area is broken into many cells, and each cell has its own receiver/transmitter. Calls are handed off from one receiver/transmitter to the next as the user moves between cells. Central Office: Telephone company facility where subscriber lines are terminated on switching equipment, from which connections can be made to local and long distance points. Centrex: Business telephone service offered by local exchange carriers that is similar to a PBX but with the switching equipment located in the telephone company central office. CLASS: Custom local area signaling services. (Bellcore service mark.) Includes number-translation services such as call forwarding, caller identification, automatic recall, distinctive ringing, call waiting, and others. Coax, Coaxial Cable: A cable composed of an insulated central conducting wire, inside a cylindrical conductor, with a buffer layer in between. Carries much more information than copper "twisted pair" cables; offers broadband capability. Used primarily for data or television signals. Codec: Coder/Decoder. Device used to convert audio or video signals from analog to digital form and vice versa. Common Carrier: A company that is recognized by an appropriate regulatory agency as providing communications service to the general public on a non-discriminatory basis. Common carriers cannot exercise any control over content of the messages they carry. Competitive access: see alternate access. Compressed Video: Digital signals can be compressed by various methods to save bandwidth, storage, and transmission time. Only the changes in the moving frames are captured and transmitted. Compression Technology: A technique that allows transport of multiple video signals within a 6 MHz (or equivalent) band width. Converter: A device allowing a TV set to receive cable signals. Sometimes descrambles encrypted signals as well. Customer First: Name given by Ameritech to its current tariff request which essentially deregulates subscriber loops. Database: An organized collection of files and information stored on a disk and available for update and retrieval. DBS: Direct Broadcast Satellite. "Cable" service using a satellite dish. Generally refers to high-power satellite that can be received by small 18-24 inch dishes. The 6-foot-plus diameter dishes already common in the U.S. are generally called TVRO (TV Receive-only) or backyard dishes. DBS is known overseas as "direct-to-home" (DTH). Digital: Information expressed in binary code; digital transmissions are by discrete signals (bits) rather than continuously variable analog waves. Digital processing and transmission allows for very high speed data communication, voice processing and compressed video. Distance Education, Distance Learning: The application of information technology (and infrastructure) to educational and student-related activities linking teachers and students in differing places.. Distant signal: A broadcast station from another market imported and carried by a cable system. Distribution Plant: The hardware of a cable system: amplifiers, trunk cable and feeder lines, attached to aerial support structures or fed through underground ducts or conduits. Downgrade: A decrease in subscriber's level of service. Downlink: Transmission link from a satellite to a ground receiving station. Downstream: Signals traveling from the headend to subscribers. Drop: Cable from a tap at the pole or pedestal connecting to the subscriber's home . DS-0, DS-1, DS-3: Digital services-levels 0, 1 and 3. DS-0 is the worldwide standard speed for one digital voice signal (64000 bps). DS-1, in North America, equals 24 voice channels or 1.544 Mbps. DS-3 equals 28 DS-1 channels, or 44.7 Mbps. DTMF: Dual tone multi-frequency. Generic term for "touch-tone," which is an AT&T service mark. Electromagnetic Spectrum: The frequencies (or wavelength) presenting a given electro-magnetic radiation. A particular spectrum could include a single frequency or wide range of frequencies. Electronic Sweep: Variation in the frequency of a signal over a whole band as a means of checking the response of equipment under the test. Equal Access: Under divestiture, subscribers must be able to reach all long distance common carriers by dialing "1." Exchange Area: Geographic area-generally surrounding a telephone central office-in which telephone services and prices are the same. FCC: Federal Communications Commission, established in 1934 to regulate all electronic interstate communications, set prices, determine standards, and allow access. FDDI: Fiber distributed data interface. An emerging standard for computer LANs operating at 100 MBPS over fiber optic cable. Feeder Cable: Cable that takes signals from the trunk line to the subscriber area and to which subscriber taps are attached. Fiber Optic: Thin glass strands through which light beams are transmitted; capable of carrying very large amounts of information over long distances; the technology of guiding and projecting light for use as a communications medium. Fiber is very efficient both in terms of bandwidth capacity, electricity requirements and quality of the signal delivered. FITL: Fiber in the Loop. Franchise: A contractual agreement between a cable operator and city or other governmental body to offer cable service. Required because operators need to run across or under public rights-of-way. Franchise authority: The governmental body responsible for specifying the terms of a franchise, awarding it and regulating its operation. Usually a local municipality or county, but some states regulate cable on the state level as well. Frequency: The number of complete cycles of a periodic activity which occur in a unit of. time, i.e., the number of times the quantity passes through its zero value in the same sense unit time. If T is the period of a repetitive phenomenon, then the frequency f is 1/T. In SI units the period is expressed in seconds and the frequency is expressed in hertz. Ground Block: A conducting connection by which an electric circuit or equipment is connected to end or to some conducting body of relatively large extent. HDTV: High Definition Television. Headend: The electronic equipment located at the start of a cable television system usually including antennas, earth stations, preamplifiers, frequency converters, demodulators, modulators, and related equipment. Hertz: (Hz) cycles per second. Homes passed: The total number of homes passed by cable plant and capable of subscribing to service. Hit/Electronic Hit: A discrete signal transmitted to a decoder to authorize/deauthorize service. Hub: A communications center: a point at which channels are interconnected. IEEE: Institute of Electrical and Electronics Engineers. INET: Institutional Network. Generally dedicated to linking government and other public buildings for such uses as training, meetings, data and voice interconnection, and the like. Provided by cable operators pursuant to [47 U.S.C. 531 ] for public, educational, and governmental use; not available to consumers. Interactive multimedia: Multimedia means the integration of distinct modes of expression (video, audio and data) into one communication. Interactive means that the recipient shapes the message. Current shopping networks can brag about being "interactive" all day, but they wouldn't fit that definition. Interconnect: The transmission of one or more services on two or more cable systems. As a noun, an interconnect is an advertising cooperative allowing an advertiser to show its commercial simultaneously on all the cable systems in the market. Internet: A network of networks; the U.S. Internet usually refers to the collection of inter-university networks using the TCP/IP communications protocol providing such services as electronic computers, database access, etc. The Internet is connected to the Bitnet and to NREN. Future Internet services will include audio and video transmission and multi-media communications. IRD: Integrated receiver/descrambler. A receiver for satellite signals that also decodes encrypted or scrambled signals. ISDN: Integrated Services Digital Network or "I Still Don't Know." A telephony-based hierarchy of digital switching and transmission systems that provides voice, data and video in a unified manner. A new standard for end-to-end digital networking. ITFS: Instructional Television Fixed Service. Local (i.e. 25-mile radius one-way broadcast channels that operate at very high microwave frequencies. IXC: Interexchange carrier. Long distance carriers, as opposed to LECs. IXCs are regulated by the FCC and provide inter-LATA service; LECs are regulated by the state Public Utility Commissions. JPEG: Joint Photographic Experts Group; sets standards for digitalization of photographs.[also a still-picture compression method developed by JPEG] LAN: Local area network. Data communications network with a limited geographic area, usually single or a few contiguous buildings. LATA: Local Access Transport Area. The geographic area in which a LEC can offer long-distance services. Created by divestiture. Leakage: Undesired emission of signals bleeding out of a cable television system generally through cracks in the cable, corroded or loose connections or loose closure devices. Leased Channels: Channels leased to independent programmers pursuant to the terms of Section 612 of the Communications Act. [47. U.S.C. 532] LEC: Local Exchange Carrier. The local telephone company, a BOC or an independent, that provides subscriber lines and local calling services. Except in special cases, LECs have a monopoly on service within their LATAs, and cannot offer inter-LATA services. Level of Service: See "tier." Line Extension: The use of an amplifier to compensate for loss on distribution feeder lines. LMDS: Local Multi-point Distribution System. Local Origination (LO): Programming carried on a cable television system over one or more channels and subject to exclusive control of the cable operator. Local Service Area: The geographic area being served by the cable operator. MATV: MATV: Master Antenna TV System. One broadcast antenna for an entire apartment building. Mbps: Megabits per second, or million bits per second. A measure of the amount of data transmitted in a fixed amount of time. MDU: Multiple Dwelling Unit. An apartment building. MFJ: Modified Final Judgment. The federal court ruling that set up the rules for divestiture of the Bell System that restricted ATT and the Baby Bells from entering many businesses. MHz-megaHertz: One million Hertz. Microwave: Radio frequency spectrum signals between 890 Megahertz and 20 GigaHertz. Common form of transmitting telephone, facsimile, video, data, and radio "conversations" for both end users and carriers. Microwave signals only travel in straight lines. Also used to transmit to and from satellites. MMDS: Multi-channel, Multi-point Distribution System. Commonly known as "wireless cable". Modem: Modulator-demodulator. Device that converts digital computer signals to analog, voice- grade signals so that they can be transmitted over telephone lines. Modulation: Variation of a carrier wave amplitude, frequency or phase by a baseband signal. MPEG: Motion Picture Experts Group; sets technical standards for digitalization of films. see JPEG MSO: Multiple System Operator. A company that operates more than one cable system. Multiplex: To transmit two or more signals simultaneously over a single transmission channel. Cable networks refer to multiplexing when they launch a separate channel under the same brand name. E.g., MTV has been considering "multiplexing" into MTV:Rap, MTV:Rock, etc. Must-carry: Under the 1992 Cable Act a broadcast station may tell any cable operator in its market that it must be carried on that system. For years operators had dropped weak stations, often religious or foreign-language broadcasters, in favor of cable networks. A station electing must-carry status cannot receive payment for its signal. A strong station that believes it has leverage over cable operators can instead seek payment by opting for "retransmission consent". NAB: National Association of Broadcasters. NATOA: National Association of Telecommunications Officers & Advisors; local telecommunications regulators; an affiliate of the National League of Cities. NCTA: National Cable Television Association. NII: National Information Infrastructure, the formal, federal term for the electronic superhighway concept. Node: A branching or exchange point. NREN: National Research and Education Network. The proposed, federally-funded, high capacity digital "electronic highway" providing the backbone links for the Internet. NTIA: National Telecommunications and Information Agency, an agency of the Department of Commerce. Off-air: Refers to broadcast signals from TV stations, as opposed to satellite-delivered networks. One-Call: Trade name for service that marks utility lines for construction of cable television systems. One-Way Communication: A mode of communication such that information is always transferred in one preassigned direction only. Optical Fiber: Hair-thin glass fiber which allow light beams to be bent and reflected with low levels of loss and interferences. Origination Point: In a signaling network, a signaling point in which a common channel signaling message is generated. Outage: A service disruption. Outlet: A connection terminal which connects a television terminal through a cable, using a matching transformer at the receiver terminals to the cable system. PANS: "Pretty Amazing New Stuff" ISDN -type service (See POTS) Parental Control Devices: Devices enabling subscribers to block reception of channels so the kiddies can't watch MTV or Spice. PBX: Private Branch Exchange. A private telephone switching system, usually located on the user premises. Connected to a common group of lines from one or more telco central offices to provide services to many users internally. PCS, PCN: Personal Communications Service, Personal Communications Network. Sort of a low-power cellular system. A system of small hand-held wireless computer-based devices combining computing, communications and personal notebooks/organizers. PEG: Public, Educational, or Governmental Access. (See Access Channel) Pay cable: A network requiring an monthly fee in addition to the "basic" cable charge, usually a movie or sports channel. Ex: HBO, Showtime, Disney Channel. Also called "premium" channels. Overseas, however, "pay" TV generally includes any kind of TV programming not free to the viewer, including cable, wireless cable or direct broadcast satellite. Penetration: The percentage of TV homes subscribing to cable TV. Basic penetration is the number of homes passed by the system who actually subscribe. Pay penetration is the number of units of a pay services divided by the number of basic subscribers. Because many subscribers take more than one pay network, say HBO and Cinemax together, pay penetration can exceed 100 percent. Pole attachment fee: Cost to cable operators to rent space to attach cable to telco and power poles. POP: Point of Presence. Physical location in a LATA where an ITX connects to the network of a LEC. POTS: "Plain Old Telephone Service." Basic service consisting of a plain telephone line, a plain telephone, and access to the public switched network, and nothing else. PPV: Pay-Per-View. Premium channel: See pay cable. Programming Services: Cable service tier(s) above basic service; usually contains the more desirable satellite-delivered services (MTV, ESPN, CNN, TNT, etc.). Often marketed as as either "satellite" service, "enhanced" or "expanded" basic. Regulated by the FCC upon complaint (FCC Form 329) by either a subscriber of the franchise authority. PUC: Public utilities commission. State agency regulating telephone and electric utilities. Called public service commission in some states. RBOC: Regional Bell Operating Company. Holding company that owns one or more BOC. REA: Rural Electrification Administration. Federal agency that makes loans to extend power and telephone services into rural areas. Residential: Term used to describe subscribers who are individuals or families and receive cable television in their homes. Retransmission consent fees: Compensation paid by a cable system for the right to retransmit a local TV station to its subscribers. Under the 1992 Cable Act stations for the first time could demand payment or other compensation for carriage of signals. RF: Radio Frequency. RFP: Request for Proposal. Generally asks for suppliers to bid on a contract. RSA: Rural Service Area, as defined by the Federal Communications Commission. Scramble: Distort signal so as to render a TV picture unviewable, while permitting full restoration with a properly authorized decoder or descrambler. SCTE: Society of Cable Television Engineers. SMATV: Satellite Master Antenna TV System. Uses a satellite dish to distribute cable programming to an entire building. Competes with the local cable company. Telecommuting: Commuting to another location electronically (e.g., by computer and telephone rather than physically. Telemedicine: The application of information technology (and infrastructure) in the health care industry in support of patient care and patient-related activities. Tier/Service Tier: Different packages of cable television service varying in number of accessible channels, services and price. Transmission Facilities: Those facilities capable of dispatching a signal, message or other form of transmission by means of wire, optical fiber or radio waves. Transponder: The portion of a satellite that sends and receives signals. Trunk Cables: The main distribution lines leading from the headend of the cable television system to the various areas where feeder lines we attached to distribute signals to subscribers. TVRO: Television Receive-Only satellite dish. Those big dishes in people's backyards and near cable headends that receive satellite signals. Two-Way Communications: A cable television system with the capacity to conduct signals to the headend ("upstream") as well as away from it ("Downstream"). UHF: Ultra High Frequency. Corresponding to electromagnetic signals in the range from 300-3000 MHz Channels 1+83 on the television dial. Universal Service: The concept that residential telephone service be priced low enough so that everyone in the U.S. could afford it. Uplink: Transmission link from all earth station to a satellite. Upstream: Signals traveling from subscribers to the headend. VHF: Very High Frequency. Corresponding to electromagnetic signals in the range from 30 to 300 MHz Channels 2-13 on the television dial. VHS: Video Home System; most popular 1/2" VCR format. Video Dial Tone: An FCC ruling allowing for limited video services to be delivered by telephone companies in their service areas. Just as a telephone gives a dial tone allowing you to call anyone you want, "video dial tone" allows subscribers to connect with a several different packagers of TV services. Designed in response to objections about telcos being able to control content. Telcos simply lease capacity to outsiders who decide whether or not to sell MTV. Seen as a competitor to cable television. Video Teleconference: Real-time, usually two-way transmission of video images between two (or more) locations. Meet by satellite. Virtual: A service that appears to be something it is not. For example, a virtual private line appears to the user to be a dedicated circuit, but is really ordinary dial-up service that is available to the subscriber on demand. VSAT: Very Small Aperture Terminal. Small satellite receive dishes, making it economical to serve isolated locations with voice, video and data services. Two-way VSATs allow for return data transmission. WAN: Wide Area Network. Wireless cable: A system transmitting TV signals to subscribers via microwave rather than coaxial cable.