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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 PEG.)

Analog
Digital / Two different kinds of communications signals. Analog is the continuously varying electrical signal in the shape of a wave (such as a radio wave), transmitted electronically. Traditional television signals are transmitted in analog format. Digital is based on a binary code in which the picture or audio information is sent as a series of “on” and “off” signals; it is more precise and less subject to interference than analog. (See HDTV.)

ATM
Asynchronous transfer mode. A set of standards for transmitting many types of baseband digital signals over a network. Very efficient for sharing channels among bitstreams of varying bit rates.

Bandwidth
This is the range of signal frequencies that can be carried on a communications channel. The capacity of a channel is measured in cycles per second, or Hertz (HZ), between the highest and lowest frequencies. While this indicates the channel’s information-bearing capacity, it is more commonly expressed as “bits per second”. Bandwidth varies according to the sort and method of transmission.

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.

Broadband
This term has a number of meanings. It was coined originally to describe a channel with more bandwidth (bits per second) than a standard voice grade channel, usually a 48 KHz link, equivalent to twelve voice grade channels. Such channels are gradually being superseded by digital circuits. Today, the term refers to the ability of a network to carry digital signals at the high bandwidth used by cable television, ranging from 550MHz to 1GHz. A single TV channel requires 6MHz. In addition, the term  “broadband” is often used loosely to refer to high-speed Internet service.

Building-by-Building Disposition
This phrase is used in the FCC’s MDU inside wiring to describe a situation in which an MDU owner decides to convert an entire building or complex of buildings to a new video service provider.

Bulk Contract
A contract for the provision of video, DBS or ISP services by a PCO or MSO to an MDU which covers all units in the community, rather than a contract between the provider and an individual MDU resident.

Cable Act
In 1992, both the Senate and the House overrode a presidential veto to pass the Cable Act. Designed to protect consumers from escalating cable TV rates, the law regulated the cable industry but did not address the issue of competition from telecommunications companies.

Cable Home Wiring
The internal wiring contained within the premises of a subscriber which begins at the 12-inch demarcation point, excluding any active elements such as amplifiers, converter or decoder boxes or remote control units.

Cable Home Run Wiring
The wiring extending from the “demarcation point” (i.e., usually, a point 12 twelve inches outside of an MDU resident’s unit) back to the point (lockbox or pedestal) at which the wiring first becomes dedicated to an individual resident’s unit.

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 Services Bureau
The division of the FCC that regulates the cable television industry. The Cable Services Bureau (CSB) enforces regulations that were designed to ensure competition among cable companies, satellite companies and other entities that offer video programming services to the general public. The Bureau is responsible for several areas, including: mandatory carriage of television broadcast signals; commercial leased access; program access; over-the-air reception devices; open video systems; commercial availability of set-top boxes; and accessibility of closed captioning and video description on television programming. CSB also resolves appeals of local rate orders issued by franchising authorities and addresses issues concerning the computation of the franchise fee. It issues annual reports that analyze trends and developments in the multichannel video programming industry, including pricing and the state of competition.

Capacity
The highest possible reliable transmission speed that can be carried on a channel, circuit, or piece of equipment. Capacity may be expressed as raw speed or as net throughput.

CARS
Cable antenna relay service. The official FCC designation for a set of microwave frequencies reserved for the use of cable television companies.

CATV
Community Antenna Television. A master antenna and distribution system capable of receiving, amplifying and distributing a television signal via coaxial cable to television receivers. Also known as “Cable Television.”

Channel
A range of frequencies assigned to a signal in an FDM transmission system. In North America, analog video and most other downstream channels are 6 MHz wide and correspond to one of the allocation forms defined in the ANSI/EIA542 standard.

CLEC
Competitive Local Exchange Carrier. A telephone company that competes with the already established local telephone business by providing its own network and switching. The term distinguishes new or potential competitors from established local exchange carriers (local exchange carrier) and arises from the Telecommunications Act of 1996, which was intended to promote competition between both long-distance and local phone service providers. North American Telecom and Winstar Communications are examples of CLECs (which generally are listed as simply “local exchange carriers.”).

Closed-Captioning
A system used to transmit captioning information to hard-of-hearing viewers, allowing text to overlay the picture. The system has been expanded to permit transmission of other types of data, most notably the V-chip rating data.

Coaxial Cable
A type of wiring that is also widely used in the cable television industry, and can carry voice, data and video simultaneously. The coaxial (or “coax”) cable consists of an inner conductor on which signal voltage is impressed with respect to the shield. The center conductor is surrounded by a dielectric, then a shield. Frequently, an insulation layer surrounds the shield.

Common Carrier Bureau
The division of the FCC that regulates long distance and local wireline telephone service to consumers. Telephone companies (referred to as “common carriers”) generally provide consumers with voice, data and other telecommunication transmission services. The CCB ensures that everyone has rapid, efficient, nationwide and worldwide access to these services at reasonable rates. CCB is also responsible for consumer protection in telecommunications. It develops rules and policies to protect consumers from slamming and cramming, and ensures Truth-in-Billing and Truth-in-Advertising. The Bureau additionally takes measures to encourage the development of competition for local and long distance services. It works to help open local markets to competition by deciding when and how companies’ networks should interconnect and how phone numbers should be allocated. CCB reviews proposed mergers of telecommunications companies and determines when a local telephone company has met the Congressional requirements that will allow it to begin selling long distance services.

Consumer Information Bureau
The Consumer Information Bureau (CIB) is a one-stop-shopping place for information regarding FCC policies, programs and activities. Through the Bureau’s toll free numbers, 1-888-CALL-FCC (voice) and 1-888-TELL-FCC (TTY), and website, www.fcc.gov/cib, the public is given access to updated consumer information.

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.

CSR

Customer service representative. An employee of a cable system who handles incoming telephone calls from customers.

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Dark Fiber
An inactive fiber-optic strand without electronics or optronics, i.e., no connected transmitters, receivers, regenerators, etc.

Data Compression
A way of reducing the amount of data to be transmitted by applying an algorithm to the basic data at source. A decompression algorithm expands the data back to its original state at the other end of the link. Digital Video requires up to 45 Mbps for reasonable performances but with compression can achieve the same in one to three Mbps.

DBS
Direct (Digital) Broadcast Satellite Service. Full motion television programming transmitted via satellite directly to the user, who receives video and audio information using a satellite antenna or receiver dish less than 1 meter diameter. This is a one-way (outgoing from origination site) transmission. DBS is the most significant competitor to cable in the provision of direct (non-over-the-air) video broadcasting nationwide. Major DBS providers include DirecTV (60% market share), Echostar (Dish Network, 39% market share) and WSNet (about 1% market share).  DBS has not significantly penetrated the MDU market.

Demarcation Point
As used in the FCC’s MDU inside wiring rules, this term refers to a point on the wiring located approximately 12 inches outside of an MDU resident’s individual unit. On the resident’s side of the demarcation point, the inside wiring is called “cable home wiring,” and on the other side, “cable home run wiring.” If the wiring at the12 inch demarcation point is “physically inaccessible,” the demarcation point is located at the point where the wiring is first physically accessible outside of the subscriber’s unit. The demarcation point is physically inaccessible if accessing the wiring at that point would require significant modification or damage of pre-existing structural elements (e.g., the wiring is embedded in brick, metal conduit or cinder block), and would add significantly to the physical difficulty and/or cost of accessing the wiring. IMCC believes that the FCC will soon broaden its definition of physically inaccessible to include, for example, wiring behind plaster or wallboard. Wiring enclosed behind hallway molding is not currently considered to be physically inaccessible.

Deregulation
Removal or lessening of regulations governing a communications service provider.

Descrambler
Electronic circuit that restores a scrambled video signal to its original form. Television signals, especially those transmitted by satellite, are often scrambled to protect against theft and other unauthorized use.

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.

Divestiture
The break-up of the AT&T monopoly into 7 regional Bell operating companies, Bellcore, and the 22 Bell operating companies. Divestiture resulted from the 1984 Modified Final Judgment, which settled the government’s long-standing antitrust suit against AT&T.

DOCSIS
Data-over-cable service interface specification. The formal name of the cable modem standard produced by a consortium led by CableLabs.

Downstream
Signal flow from a headend toward subscribers. Also known as the forward direction.

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

DSL
Digital Subscriber Line. a generic term encompassing a family of moderate to high- speed Internet access using a subscriber’s existing copper lines.

Enforcement Bureau
The Enforcement Bureau (EB) is responsible for ensuring compliance of numerous statutory and regulatory provisions designed to protect consumers. There are four Divisions within EB, including Telecommunications Consumers, Investigations and Hearings, Technical and Public Safety and Market Disputes Resolution.

EPG
Electronic Program Guide. A display on the TV of a selection of programs available to the subscriber. The EPG may include other features such as information on programs or interactivity, including automatic tuning to selected programs or the ability to program a VCR.

Exclusive Contract
As used in the private cable industry, an access or service agreement between a video provider and an MDU (or MTE) owner that gives the provider the exclusive right to provide service to residents in the building or community, to the exclusion of all other video providers.

Expanded Basic Service
A subscription service offering by a cable company or PCO that consists of basic service plus more advertiser-supported channels (as opposed to pay services).

FCC
Federal Communications Commission. 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 Optic Cable
A medium for transmission comprised of many glass fibers. Light emitting diodes send light through the fiber to a detector that converts the light back to an electrical signal for interpretation. Fiber was initially used for network backbones but, as the cost of fiber has come down, it is gaining dominance in all areas of communications. Advantages include huge bandwidth, and immunity to eavesdropping, interference and radio activity.

Fifth Amendment
The Fifth Amendment to the United States Constitution bars the federal government from “taking” (whether directly, or by confiscatory regulation) private property without providing “just compensation” to the property owner. The FCC’s OTARD and inside wiring rules raise Fifth Amendment questions because they limit a property owner’s control over property.

Franchise
Contractual agreement between a cable operator and a governmental entity that defines the rights and responsibilities of each in the construction and operation of a cable system within a specified geographic area. In general, any cable operator using coaxial cable to cross a public right of way is required to obtain a franchise from the relevant local franchising authority (“LFA”), usually a municipality or county. Typically, the franchise agreement grants the cable operator a limited monopoly in return for the operator’s obligation to serve all residents of the franchise area who desire service. Under federal law, no LFA may grant an exclusive franchise to any single cable television provider.

Gulf Power
Refers to a recent decision of the 11th Circuit Court of Appeals in a case called Gulf Power Co. v. FCC, 208 F.3d 1263 (11th Cir. 2000). The court ruled that the Pole Attachments Act (47 U.S.C. § 224) does not give the FCC the authority to require utilities to provide non-discriminatory access for providers of wireless communications and high-speed Internet services. The Gulf Power case is currently being reviewed by the United States Supreme Court.

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 a least 720 lines per screen.

HFC
Hybrid fiber-coax. A network for transmitting signals modulated onto RF carriers that includes a linearly amplitude modulated optical link followed by a coaxial distribution network.

Headend

The central transmission point for an MSO or PCO system from which programming is distributed to users. In the MDU environment, the headend consists of a satellite reception dish and all electronic equipment needed to descramble the video signal for distribution to individual units. The cost of constructing one or more headends places PCOs at a significant competitive disadvantage with respect to franchised cable operators because the cable operator usually only requires a single headend to serve any particular community, whereas a PCO must usually construct a headend for each MDU building or complex of buildings serviced.

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ILEC
Incumbent Local Exchange Carrier. A telephone company in the U.S. that was providing local service when the Telecommunications Act of 1996 was enacted. ILECs include the former Bell operating companies (BOCs), which were grouped into holding companies known collectively as the regional Bell operating companies (RBOCs) when the Bell System was broken up by a 1983 consent decree. ILECs are in contradistinction to CLECs (competitive local exchange carriers). A “local exchange” is the local “central office” of an LEC. Lines from homes and businesses terminate at a local exchange. Local exchanges connect to other local exchanges within a local access and transport area (LATA) or to interexchange carriers (IXC) such as long-distance carriers AT&T, MCI, Qwest and Sprint.

IMCC
Independent Multi-Family Communications Council.  A professional organization of MDUs and PCOs, formerly known as Independent Cable & Telecommunications Association.

Inside Wiring Rules
FCC regulations governing the disposition of cable wiring inside MDUs. These rules are designed to enhance competition among video service providers by making existing wiring available for competing providers’ use. The FCC’s inside wiring rules may be found at 47 C.F.R. §§ 76.800 et. seq. A brief primer on the FCC’s MDU inside wiring rules may be found elsewhere on the IMCC website.

International Bureau
The division of the FCC that deals with international aspects of the communications industries. The International Bureau (IB) serves as the focal point for international activities and satellites services, and advises the Commission on worldwide communications. Its mission is to promote innovative, efficient, reasonably priced, widely available, reliable, timely and high quality domestic and international communications services for consumers. In addition, the IB monitors the effects of significant legislation, such as the World Trade Organization Agreement on Basic Telecommunications Services, which helped decrease rates paid by US consumers for international service, among other benefits.

Internet
The Internet is a collection of many networks worldwide which is commonly referred to in two ways: The internet (lowercase i) is any collection of separate physical networks, interconnected by a common protocol, to form a single logical network. The Internet (uppercase I) is the worldwide collection of interconnected networks, which grew out of the original ARPANET, that uses Internet Protocol (IP) to link the various physical networks into a single logical network.

ISP
Internet Service Provider. A company or institution that provides a connection between a user’s computer and the Internet.

LAN
Local Area Network. A data communications network that can cover a limited area of up to about six miles in radius, with moderate to high data speeds. The machines linked by a LAN may all be in the same building or a group of buildings in relatively close proximity. It is user owned and does not run over leased lines, although it might have gateways to the PSTN or other private networks.

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.

LEC
Local Exchange Carrier. A local telephone company, i.e., a communications common carrier that provides ordinary local voice-grade telecommunications service under regulation within a specified service area. Historically, a LEC is a Regional Bell Operating Companies (RBOC) that sells local telephony service over twisted-pair copper wire and must (under Federal law) make that infrastructure available to CLECs for their use.

Local Network
Set of telecommunications links within a limited area.

Lockbox
In the MDU environment, this term refers to the location (usually a locked metal box containing one or more distribution panels) where the cable home run wiring (extending to the demarcation point) begins.

Loretto
Refers to a 1982 decision of the United States Supreme Court, Loretto v. Teleprompter Manhattan CATV Corp., 458 U.S. 419 (1982). The Court ruled that any government action (in this case, New York’s mandatory access law) that effects a “permanent physical occupation of private property,” even if minimal, violates the Fifth Amendment, unless just compensation is paid. The Loretto decision often comes up in discussions of the constitutionality of the FCC’s MDU inside wiring and OTARD rules, and is a crucial ruling in protecting an MDU owner’s property rights.

Mandatory Access
Generally refers to state statutes (or local regulations) that provide a video provider (usually the locally franchised cable operator) or providers with a legal right to install MDU inside wiring and provide service to residents without the property owner/manager’s consent. Most mandatory access laws impede competition because they prevent PCOs from entering into exclusive service contracts with MDU owners. Currently, nineteen states (including the District of Columbia) have mandatory access statutes in effect. (A list of these states is included elsewhere on the IMCC website.)

Mass Media Bureau
The division of the FCC that regulates the radio and broadcast television industries. The Mass Media Bureau (MMB) ensures that consumers have access to interference-free radio and television services that are in the public interest. To achieve this, MMB issues licenses for radio and television stations and establishes regulations to make certain that these stations serve their local communities through programming and advertising. Information about these obligations and how broadcast stations are licensed is available in a manual produced by MMB, called “The Public and Broadcasting.” This manual also describes the public inspection file, which contains publicly available documents relevant to the operations of all radio and TV stations.

MDU
Multi-Dwelling Unit. A multi-dwelling building or complex of buildings dedicated to residential use, such an apartment, condominium or co-op building. Within the industry, MDUs (residential buildings) are to be distinguished from MTEs (commercial buildings).

Modem
Abbreviation of modular/demodulator, the modem converts digital computer signals into analogue form for transmission over analogue telephone systems. Modems work in pairs, so at the other end of the channel the signal is returned to digital form. Remember, traditional telephone networks were designed for the human voice, which are analogue, not digital computers.

NPRM
Notice of Proposed Rulemaking. A term of administrative law referring to a procedure used by governmental agencies (such as the FCC) to begin the process of promulgating a rule. The agency publishes the NPRM in the Federal Register describing the factual and legal bases for the proposed rule as well as its rationale. In general, any member of the public has ninety days from the date of publication in which to file written comments on the proposed rule.

MSO
Multiple System Operator. Term used to designate a franchised cable TV organization that has cable systems in multiple locations.

MSO-SO
Master System Operator – System Operator. This term is used to refer to a business arrangement used by DirecTV, a major DBS provider, in the provision of video services to MTEs and MDUs. DirecTV distributes programming through an MSO such as PACE, and the MSO uses an System Operator to install, maintain and manage the infrastructure needed to provide video service to residents of the MTE or MDU.

MTE (U)
Multi-Tenant Environment (or Unit). According to the FCC, any contiguous premises under common ownership or control that contains two or more distinct units occupied by different tenants. Under the FCC’s definition, MTEs include, for example, apartment buildings (rental, condominium or co-op), office buildings, office parks, shopping centers and manufactured housing communities. The FCC’s definition of “MTE” – insofar as it includes residential buildings – is inconsistent with industry usage, according to which an MTE is a commercial building (or buildings), in contrast to an MDU, which is a residential building. This inconsistency has lead to some confusion in certain FCC regulations.

Multiplexing
Reversible technique for combining signals for convenience in transmission.

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. The Supreme Court voted 5-4 in 1997 to uphold must carry for analog broadcast television signals.

MVPD
Multichannel Video Program Distributor.  All providers of multichannel TV, including MSOs, PCOs, CLECs and DBS systems.

Open Cable
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.

OTARD
The FCC’s Over-the-Air-Reception Devices Rule. This rule can be found at 47 C.F.R. § 1.4000 and has been in effect since October 14, 1996. OTARD prohibits restrictions that impair the installation, maintenance or use of antennas (primarily DBS dishes) used to receive video programming. The rule applies to viewers who place video antennas on property that they own or that are within their exclusive control, including apartment residents, condominium and co-op owners who have an area where they have exclusive use, such as a balcony or patio, in which to install the antenna. However, the availability of a central antenna (located, for example, on the roof of the building) may allow the management entity (e.g., condominium association, landlord, property owner) to restrict the installation of antennas by individuals. Restrictions based on the availability of a central antenna are permitted provided that: (1) the viewer receives the particular video programming service that he/she desires and could receive by means of an individual antenna; (2) the quality of the video reception in the viewer’s home using the central antenna is at least as good as that which the viewer could receive with an individual antenna; (3) the costs associated with the use of a central antenna are not greater than the costs of installation, maintenance and use of an individual antenna; and (4) the requirement to use the central antenna (instead of an individual antenna) does not unreasonably delay the viewer’s ability to receive video programming.

OVS
Open Video System.  A video distribution facility used by a telephone company to provide video services. Assuming that the telephone company certifies that it complies with certain non-discrimination and other requirements, the FCC may certify the company as an OVS operator exempt from regulation under Title II (“common carrier”) of the Communications Act of 1934, and subject to reduced regulation under Title IV (“cable services”).

Pay Cable
A network of 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.

Pay-Per-View
Pay service that enables a subscriber to order and view events or movies on an individual basis.

PCO
Private Communications Operator.  Smaller, independent cable company that competes with an MSO, usually in the multi-family environment.

Pedestal
For a franchised cable operator in the MDU environment, the point at which cable wiring becomes dedicated to an individual unit. (See Lockbox.)

PEG
Public, educational, and government. A set of locally generated channels many systems are required to carry as a public service.

Perpetual Contract
An access or service agreement between a video provider and an MDU (or MTE) owner that contains (explicitly or implicitly) no specific termination date. Perpetual contracts include, for example, service agreements that are automatically renewed or extended whenever the provider’s franchise is renewed.

POE
Program of Excellence. A set of performance standards created by IMCC for PCOs. The POE is designed to be used in contract negotiations setting PCOs off from their competitors, and as benchmarks for the improvement of PCO products and services by meeting the needs of property owners and their residents, thus increasing PCO penetration in the MDU market.

Pole Attachments
Refers to 47 U.S.C. § 224 (the Pole Attachment Act). Section 224 provides that a “utility” must allow any cable television or telecommunications provider to attach wiring to the utility’s pole, duct, conduit or right-of-way at “just and reasonable” terms, rates and conditions. For purposes of Section 224, an ILEC is considered to be a “utility.” The FCC has recently issued a rule (WT Docket No. 99-217) requiring utilities to provide non-discriminatory access under Section 224 to ducts, conduits and rights-of-way within MTEs and MDUs.

Program Access
A series of FCC rules, established in accordance with federal law, that are generally designed to ensure that cable operators have competitive access to cable programming. Specifically, the program access rules prohibit discriminatory acts and practices by program vendors and cable operators in cases where these entities are financially related. The program access rules may be found at 47 U.S.C. § 548 and 47 C.F.R. §§ 76.1003 et. seq.

Public Right of Way
A pathway or road with a specific description that is dedicated to a public use. The term includes any strip of land over which public facilities such as highways, railroads, or power lines are built.

Public Utility
Privately owned business entity, subject to government regulation that provides an essential commodity or service, such as water, electricity, transportation, communication to the public.

Regulation
A rule having the force of  law established by the federal or state government which establishes procedures that a utility or other regulated entity must follow.

REIT
Real Estate Investment Trust.  Investment groups who may own and/or manage MDUs

Report and Order (“R & O”)
Term used by the FCC to designate the document setting forth its final agency action in proceedings such as adjudications or rule-makings.

ROE
Right of Entry Agreement. An agreement between a PCO and an MDU owner setting forth the parties’ respective rights and obligations with regard to the PCO’s provision of video (and/or other communications) services to residents of the MDU.

Scrambling
In cable television, the process of modifying an analog TV signal so that it cannot be received by a television receiver. In data transmission, scrambling refers to the process of randomizing the bit pattern of a transmitted signal to prevent peaks in the spectrum of the modulated signal. Note that the cable television and data transmission definitions are not equivalent. The cable television industry usually uses the data transmission term encryption for program denial of digital signals.

Set-Top Box
Electronic equipment used to descramble television signals in a consumer’s home, usually housed in a “box” that sits atop a TV set or VCR.

SMATV
Satellite Master Antenna Television. A technology used by PCOs to deliver video services to MDU buildings. One or more satellite dishes receive broadcast signals, which are fed into a headend and distributed to subscribers within the building or complex.

Splitter
A device having three or more ports, used to divide a video signal equally among multiple paths (such as when a single cable feeds into multiple television sets) without regard for the frequency of the signal. Can also be used to combine two signals.

Tap
The component installed in the distribution cable that diverts a portion of the downstream distribution signal and splits it to feed two to eight individual subscribers. In the reverse direction, it combines the signals from subscribers and inserts them into the upstream direction of the distribution cable.

TCP
IP / Transmission Control Protocol/Internet Protocol (TCP/IP) is a transport and internetworking protocol that is a de facto networking standard. It is commonly used over X.25 and Ethernet wiring and is viewed as one of the few protocols available that is able to offer a true migration path towards OSI. It was originally developed by the US Department of Defense and is able to operate in most environments. TCP/IP operates at Layers Three and Four of the OSI model ( Network and Transport respectively). The name TCP/IP refers to an entire suite of data communications protocols. Originally known as “Internet protocol suite”, the entire family became known as TCP/IP from two of the most popular protocols which belong to it: Transmission Control Protocol (TCP) and the Internet Protocol (IP).

Telephony
The provision of telephone (voice) communications services by any method (e.g., wireline, cable, wireless).

Trunk
1. The untapped portion of a coaxial distribution network. Trunk links are typically operated at lower levels than distribution links to minimize distortions. 2. An amplifier module used in the trunk portion of a coaxial distribution system. 3. An amplifier station that contains a trunk module. It may also contain a bridge module if it is desired to create a distribution leg at that location.

Twisted Pair
A type of cable used extensively for transmission of balanced audio signals. The cable consists of two insulated conductors twisted on each other. It may or may not have a shield over the twisted pair.

Unit-by-Unit Disposition
Phrase used in FCC’s inside wiring rules to describe a situation in which an MDU owner permits two or more video service providers to compete for subscribers in individual units in a building or complex of buildings.

Upstream
Signal flow from subscribers toward a headend.

Video Conferencing
Allows participants to hold a conference from their remote desktop computers. Videoconferencing introduces new requirements to the ordinary transfer of video information. First, there is a requirement for guaranteed latency because to sustain a moving image, the next frame of information must get to the other end to avoid image freeze. In practice, the image information is highly compressed and the effects of delayed information in a video sequence is less than the effect on voice. A second requirements is synchronization. Videoconferencing includes voice and other media such as electronic chalkboard. It is important that the sound replay matches the image of the person. When the image is written on the pad, the information on the electronic chalkboard should appear at the same time. The third requirement is broadcast. In many cases, the conferences may involve more than two parties and an efficient method of sending to multiple sites simultaneously is desired.

VOD
Video on demand. A video service that allows users to select the program and exact start time interactively. In some embodiments, it allows VCR-like control of the playback (for example, pause, rewind, and fast forward). Most “VOD” today is actually “near VOD,” meaning that there is some delay between the user’s selection of programming and its playback.

Wireless
The use of frequencies in the MDS, MMDS, OFS, and ITFS ranges, reserved by the FCC for commercial use, to form a transmission service, typically for entertainment programming — usually MMDS-multichannel broadcasting to compete with or fill in a niche not served or poorly served by cable.

Wireless Telecommunications Bureau
The division of the FCC that regulates the wireless telecommunications industry. The Wireless Telecommunications Bureau (WTB) is responsible for all FCC domestic wireless telecommunications programs and policies, except those involving satellite communications or broadcasting. Wireless communications services include: cellular telephones; paging; personal communications services (PCS); public safety; and other commercial and private communications services. The Bureau is also responsible for spectrum auctions.

WWW
World Wide Web. A network of computers constituting an important component of the Internet. The World Wide Web was initially devised at CERN for allowing the academic community to gain access to scientific documents, which can contain sound and video, from a range of information servers distributed over the network. Since then it has grown enormously (there are currently several thousand WWW servers on the Internet) and has become the de facto standard for distributed information access. Client front-ends for WWW are available for the majority of commonly-available platforms including UNIX/X-Windows, Macintosh and PCs (MS-DOS and MS-Windows). These front-ends are termed browsers and usually include the necessary functionality to display the commonest media types, such as text and image data. Presentation of media types such as video is generally accomplished by invoking a separate viewer program automatically from within the browser.