Conrad L. Young’s Wired Broadband and Related Industry Glossary of Terms with Acronyms As of 15 February 2012 Open Access This document is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial
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Standards
Synchronous Optical NETwork (SONET) SONET is an optical interface standard to transport digital signals that allows inter- working of transmission products from multiple vendors. Among other things, it defines optical line rates known as optical carrier (OC) signals; the base rate is 51.84Mbps (OC-1), with higher rates being direct multiples of the base rate. (For example, OC-3 runs at 155.52 Mbps, or three times the rate of OC-1.) Synchronous Transmission Protocol A method of encoding a data transmission that does not use start and stop bits at the beginning and end of each byte to synchronize the data time clocks at each end of a connection. Instead it sets its timing signal at the beginning and end of each connection, and corrects discrepancies that arise over time by using the changing values each device on the connection sends and receives to keep their clocks “in sync.” Eliminating the start and stop bits reduces the “overhead” required to transmit each byte, and allows for increased throughput. Syndicated Exclusivity Requirement by which cable systems must black out significant portions of their distant signals in order to protect syndicated programming offered by local television broadcasters under an exclusive contract. The FCC eliminated this requirement in 1980 and re-imposed it in 1990. Syndication The sale of the right to broadcast or publish multimedia content to affiliate publishers. (Fain) System Integrators (SI) Companies that provide installation of networking equipment and possibly other services such as training or network management. System Level The level of signal in a cable television system at the output of each amplifier. Must be carefully chosen and maintained for least distortion and noise. System Loss Cable TV distribution systems are designed to compensate the cable and device losses. The spacing between cable amplifiers can increase as system losses are minimized through the proper choice of connectors, cable and related hardware. System losses are referred to as a “dB of cable” without reference to specific cable size or device losses. Generally these losses are understood to be at the highest operating frequency of the system. System Noise Refers to the random energy generated by thermal and shot effects in the system. It is specified in terms of its rms level as measured in a 4-MHz bandwidth centered within a 6-MHz cable television channel. System Operator The individual, organization, company or other entity that operates a cable TV system. System Test Plan (STP) A plan or policy for verifying system function, performance and/or compliance to a specification. Systems Management Functions in the application layer related to the management of various Open Systems Interconnection (OSI) resources and their status across all layers of the OSI architecture. Systems Network Architecture (SNA) IBM's layered protocols for mainframe communications.
T-1
T-1 Carrier System A 24-channel, time-division, pulse-code modulation, voice carrier used on exchange cable to provide short-haul trunks. Uses two pairs, in one or two cables, pulse repeaters at 6000 foot intervals. (Arris Glossary of Terms) Take Rate The ratio of homes that pay for a cable service to homes passed. Tap A tap is a device which splits off a portion of the feeder line signal for the subscriber. Tap Loss In a fiber optic directional coupler, the ratio of power at the tap port to the power at the input port. (FiberOpticsInfo) Tap Port In a directional coupler where the splitting ratio between output ports is not equal, the output port containing the lesser power. (FiberOpticsInfo) 
Tap Port Diagram courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/t TAR Total Activity Report Tariff A set rate and service schedule established by agreement between the phone company and a government-run regulatory agency, called the Public Utilities Commission. T-Carrier Generic designator for any of several digitally multiplexed telecommunications carrier systems. (FiberOpticsInfo) T-carrier System A digital transmission system that takes analog voice circuits and converts them to digital form for transmission using time division multiplexing. The T-carrier system was designed to operate at different rates, known as T1 (1.544 Mbps, equivalent to 24 channels); T2 (6.312 Mbps, equivalent to 96 channels); T3 (44.736 Mbps, equivalent to 672 channels); and T4 (274.176 Mbps, equivalent to 4,032 channels). (Without compression, a 64-Kpbs channel carries a single voice conversation). Carrier systems are not always channelized; the entire system can be used to carry high-bandwidth communications. T-Commerce Television commerce, an interactive television application which enables electronic transactions between businesses and consumers via television. TCP Transmission Control Protocol TCP/IP Transmission Control Protocol/Internet Protocol; two interrelated protocols that are part of the Internet protocol suite. TCP operates on the OSI transport layer and breaks data into packets. IP operates on the OSI network layer and routes packets. Originally developed by the U.S. Department of Defense. (FiberOpticsInfo) TDD Time Division Duplex TDM Time Division Multiplexing; a type of multiplexing where two or more channels of information are transmitted over the same link by allocating a different time interval ("slot" or "slice") for the transmission of each channel, i.e., the channels take turns to use the link. Some kind of periodic synchronizing signal or distinguishing identifier is usually required so that the receiver can tell which channel is which. TDM becomes inefficient when traffic is intermittent because the time slot is still allocated even when the channel has no data to transmit. Statistical time division multiplexing was developed to overcome this problem. (Dictionary Reference)
Time Division Multiplexing Access TDR Time Domain Reflectometer; a device that uses a principle similar to radar to detect faults in metallic pair cables. A pulse of energy is directed into the cable. If the pulse encounters a discontinuity (break, pinch, bad connection) in the cable, a certain amount of the pulse energy is reflected to the TDR. By calculating the time difference between the original pulse launch and the receipt of the reflected pulse, the TDR can determine where the discontinuity is located. Some units use a digital numeric readout as an indicator. Others display the pulse information graphically on a viewing screen. Also referred to as a Cable Fault Locator. (Arris Glossary of Terms) Tearing A term used to describe a picture condition in which groups of horizontal lines are displaced in an irregular manner. Caused by lack of horizontal synchronization. TEC Thermoelectric Cooler; a device used to dissipate heat in electronic assemblies. (FiberOpticsInfo) 
Photo of Model TC-101 TEC courtesy of Force, Inc. Tee Coupler A three-port optical coupler. (FiberOpticsInfo) 
Tee Coupler Diagram courtesy of Fiber Optics info, http://www.fiber-optics.info/fiber_optic_glossary/t TEDS TETRA Enhanced Data Services; part of TETRA standards Release 2, an evolution of TETRA release 1 to which it is backwards compatible. TEDS provides a step change in the data rates available over TETRA, thereby meeting the need for higher speed data services. Key aspects of TEDS include: • sharing the same government approved high-strength security mechanisms that make TETRA1 secure • ability to be introduced into an existing TETRA1 network as an upgrade; greatly simplifying the operations and maintenance task for the network operator and so avoiding the operational risks associated with having to deploy a separate mission-critical high speed data network • Its spectral efficiency means that TEDS can be slotted into available space within the existing TETRA frequency band, or even replacing existing carriers dedicated for data and providing substantially more capacity. This avoids a costly and time-consuming process of finding new spectrum for a separate high speed data network (Motorola) TEI Terminal Endpoint Identifier Telco A local exchange telephone carrier. Telecommunications Communicating over a distance through wire, radio, optical or other electromagnetic means. Telecommunications & Internet Protocol Harmonization Over Network (TIPHON) A project within the European Telecommunications Standards Institute (ETSI) aimed at enabling systems level interoperability for Voice Over IP technologies. ETSI has historically been focused primarily on H.323-based systems; however, they recently have become interested in MGCP-based technologies, such as PacketCable NCS. Telecommunications Management Network (TMN) A management concept that defines the relationship between basic network functional building blocks (operations systems, data communications networks, and network elements) in terms of standard interfaces. Teledensity The number of telephone lines (including wired residential and business lines) per 100 people, a rough measure of the ubiquity of the public switched telephone network (PSTN) in a country. Teledesic The name of the U.S. proposed low earth orbit (LEO) satellite system that would deploy 840 satellites for global telecommunications services. (Satnews) Telephone Number (TN) A 10-digit number that specifies the location of a particular telephone and consists of a 3-digit area code, 3-digit central office code, and 4-digit station number. Teletext Broadcast service using several otherwise unused scanning lines (vertical blanking intervals) between frames of TV pictures to transmit information from a central database to receiving television sets. Television The electronic transmission and presentation of pictures and sounds. Television Broadcast Band In North America, the UHF and VHF frequencies extending from 54 to 890 MHz assigned to television broadcast stations. These include VHF channels 2-13 and UHF channels 14-69. (Arris Glossary of Terms). The following is a summary of North America OTA TV broadcast band changes and variations from the 1940s to today. Channel 1 was removed early on as a community television reservation and given to amateur radio and other uses. Channels 70 through 83 were removed from the bandplan in the 1980s to make way for AMPS mobile phone service. These channels were mainly used in the U.S., and mainly for broadcast translators, some of which continued in operation if their frequencies were not used by cellular. Channel 37 is allocated to radio astronomy and may not be used by any station. In the U.S., channels 52 through 69 are being reallocated for other purposes as the transition to digital television broadcasting is completed for low-power TV stations. All full-power analog broadcasts ended in June 2009, and all temporary full-power digital broadcasts moved back down to the lower channels. While most other countries abandoned VHF due to its poor suitability for TV broadcasting and allocation for Digital Audio Broadcasting, the FCC chose to cut high-UHF channels instead, because frequency-use rights could be auctioned for a greater price. Channels 14 through 19 are used for two-way radio in major cities on a non-interference basis, although the transition to digital television (DTV) has caused problems in certain instances when a previously unused channel has begun to be used for DTV broadcasts. The same holds true for wireless microphones and medical telemetry devices in that band. In most regions, new digital television stations are placed on UHF (14 to 51, except 37 and sometimes 14 and 20) or high-VHF channels (7-13), although others are used in some of the more crowded media markets. With virtual channel numbering, many digital televisions group digital channels with their corresponding analog broadcasts. For example, the first digital TV stream of a station that broadcasts analog TV on channel 4 will usually appear as 4-1 or 4.1 on a DTV receiver, even though the digital transmissions may be on channel 38. Several digital subchannels can be multiplexed together, so 4-1 through 4-5 might be used by one station. Subchannel 0 (e.g., 4-0) designates the analog broadcast. In the U.S., all channels from 7-36 and 38-51 are frequently used for digital TV broadcasts. However, VHF 2 to 6 are rarely used by DTV broadcasters due to ongoing problems with impulse noise, and channel 6 being an adjacent channel to the FM broadcast band. Additionally, VHF performance is poor for mobile TV, with ATSC-M/H being the standard finalized and approved in late 2009. The VHF bandplan was modified several times before 1948. The last change was the transfer of channel 1, originally intended as a low-power (less than 1,000 watts) LPTV community channel, to two-way land-mobile radio and the six-meter amateur radio band. [1] Amateur television (ATV) is used on four channels in the 420-450 MHz (70-centimeter) amateur band; UHF TV channel 14 starts at 470 MHz. These ATV channels are popular for repeater output and direct communications and are seen over-the-air with a cable-ready tuner set to channels 57 to 60 (14 being seen on 65). ATV is also used on the other amateur bands above 450 MHz. ATV is also known as HAM TV or Fast Scan TV. (Wikipedia TV) Television Channel For NTSC, a standard 6 MHz RF channel included in the television broadcast band. For PAL and SECAM variants, a standard 8 MHz RF channel included in the television broadcast band. (Arris Glossary of Terms) Television Households A household having one or more television sets. Estimates for each county are based on an updating of ARB (American Research Bureau) TV penetration estimates. The number of households that watch television in any locality during prime-time hours determines the top 100 markets for FCC cable rules. Television Market A city or complex of closely associated cities served by commercial television broadcast signals from one or more TV stations located within the area. The FCC uses television markets for designating what kind of cable services an operator should provide in terms of signal carriage and non-broadcast channel use. Television Receiver-Only (TVRO) A satellite receive system consisting of a satellite antenna, LNA or LNB, satellite receiver and any other necessary electronic equipment and hardware needed to receive and process a satellite transmission of viewing. (Arris Glossary of Terms) Telnet A TCP/IP protocol which allows terminal-type login access to computers on the Internet for the purpose of entering remote commands. The protocol name is capitalized; when used in the form “telnet,” it refers to the client software that implements the protocol, or the act of using the protocol. Telstar The AT&T Corporation has maintained its trademark for the Telstar name and currently operates its domestic satellite system under the Telstar name. (Satnews) Tensile Strength The maximum stress that a material subjected to a stretching load can withstand without permanent damage. This is a common way of specifying the strength of optical fibers and cables. (Arris Glossary of Terms) TEP Test Execution Package Terahertz (THz) 1012 HZ. (Arris Glossary of Terms) Terminal Generally, connection point of equipment, power or signal. Any “terminating” piece of equipment such as computer terminal. Terminal Endpoint Identifier (TEI) A unique number that the telephone company switching equipment assigns to each ISDN adapter when it is turned on or connected to a telephone line. Termination An electrical load connected to a cable, device, or net-work, to terminate the unit in a specific manner. Generally a termination will have the same impedance as the unit to which it is connected. (Arris Glossary of Terms) Terminator A resistive load for an open coaxial line to eliminate reflections; usually capacitively coupled to avoid shorts in cable-powered systems. Ternary A semiconductor compound made of three elements (e.g., GaAlAs). (FiberOpticsInfo) Terrestrial Interference (TI) Interference of earth-based microwave communications with reception of satellite broadcasts. (Arris Glossary of Terms) Test Execution Package (TEP) The actual set of instructions, scripts, results tables, and any other document used to test and report compliance with certain specifications. TETRA Terrestrial Trunked Radio, formerly Trans-European Trunked Radio, a digital private mobile radio (PMR) standard defined by the European Telecommunications Standardization Institute (ETSI) that initially described a common mobile radio communications infrastructure throughout Europe. This infrastructure is targeted primarily at the mobile radio needs of public safety groups (such as police and fire departments), utility companies, and other enterprises that provide voice and data communications services. All of these groups have been high-end users of private/professional mobile radio (PMR) or public access mobile radio (PAMR) technology. This is especially true in the areas of law enforcement and public safety, where fast and accurate field communications to and from a central office (CO) or dispatcher are often critical. TETRA is a standard solution for groups that use both PMR and PAMR. Prior to TETRA adoption, when European disasters have struck, emergency response teams from different European nations had a difficult time communicating with each other, due in part to the lack of standardization in their mobile radio equipment. The TETRA standards evolved to answer this communication challenge as well as others faced or anticipated by the European Commission (EC) in its efforts to unify European countries. Based on digital, trunked radio technology, TETRA takes its features from several different technological areas: mobile radio, digital cellular telephone, paging, and wireless data. TETRA-based products come with built-in encryption features to ensure the privacy and confidentiality of sensitive data/voice communications. These products are also designed with the ability to transfer data at faster rates than seen before in mobile communications. TETRA, which originally stood for Trans-European Trunked Radio, was renamed Terrestrial Trunked Radio after ETSI found widespread interest in the TETRA standards beyond Europe's geographic borders. ETSI has had a successful history of developing communications standards that later become accepted industry-wide, such as the Global System for Mobile Communications (GSMC) standard. The TETRA Memorandum of Understanding (MoU) was created in December 1994 as a forum to represent the needs of various members of the mobile communications industry (including product manufacturers, telecommunications agencies, end users of mobile devices). (Geldart) Following regulatory changes in 2011 in Canada and the USA, allowing the use of TETRA technology in those countries, TETRA may now be deployed in all countries of the world. Information provided by the TETRA Association suggested that at the end of 2010 TETRA was in use in 121 countries. (TETRA) TFTP Trivial File Transfer Protocol (Trivial FTP) TGS Ticket Granting Server Thermal Equalizer Download 2.22 Mb. Share with your friends:
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