Telecommunications terms starting with T

499 terms

  1. tie trunk A telephone line that directly connects two private branch exchanges (PBXs).
  2. TIFF Tagged Image File Format - a graphic file format used for storing still-image bitmaps.
  3. tight buffer See buffer.
  4. tiling See block distortion.
  5. Time (1) A request by a player to suspend play while he decides what he's going to do. Simply, "Time, please!
  6. time ambiguity A situation in which more than one different time or time measurement can be obtained under the stated conditions.
  7. time availability Synonym circuit reliability.
  8. time block An arbitrary grouping of several consecutive hours of a day, usually for a particular season, during which it is assumed that propagation data are…
  9. time bomb In COMSEC, a logic bomb to be activated at a predetermined time. [2382-pt.8] 2.
  10. time code A code used for the transmission and identification of time signals. Note: In telecommunications systems, the format of the time code must be specified.
  11. time code ambiguity The shortest interval between successive repetitions of the same time code value.
  12. time code resolution The interval between two successive time code states. Note: Time code resolution is determined by the most rapidly changing symbol position within the…
  13. time constant The interval required for a system or circuit to change a specified fraction from one state or condition to another.
  14. time diversity Transmission in which signals representing the same information are sent over the same channel at different times.
  15. time division See time-division multiplexing.
  16. time guard band A time interval left vacant on a channel to provide a margin of safety against intersymbol interference in the time domain between sequential operations…
  17. time instability The fluctuation of the time interval error caused by the instability of a real clock.
  18. time interval error (TIE) The time difference between a real clock and an ideal uniform time scale, after a time interval following perfect synchronization between the clock and…
  19. time jitter Short-term variation or instability in the duration of a specified time interval.
  20. time marker A reference signal, often repeated periodically, enabling the correlation of specific events with a time scale, such as for establishing synchronization.
  21. time of occurrence The date of an event, i.e., the instant an event occurs, with reference to a specified time scale.
  22. time scale A time measuring system defined to relate the passage of temporal events since a selected epoch.
  23. time scale factor A multiplier used to transform the real time of occurrence of an event or a problem into system time, such as that of a telecommunications system or a…
  24. time server The server maintaining and distributing the correct date and time over a computer network. Note: There is usually a special time-distribution protocol.
  25. time slot Period of time during which certain activities are governed by specific regulations. [JP1] 2. A time interval that can be recognized and uniquely defined.
  26. time stamp (TS) 1. A data field in which is recorded (typically with a resolution of 1 millisecond) the cumulative variable queuing delay experienced by a packet in…
  27. time standard A stable device that emits signals at equal intervals such that their count may be used as a clock.
  28. time tick A time mark output of a clock system.
  29. time-assignment speech interpolation (TASI) An analog technique used on certain long transmission links to increase voice-transmission capacity.
  30. time-consistent busy hour (TCBH) The identical hour each day during which, over a number of days, the highest average traffic is measured. [T1.Rpt 11-1991]
  31. time-delay distortion Synonym delay distortion.
  32. time-derived channel See time-division multiplexing.
  33. time-division multiple access (TDMA) A communications technique that uses a common channel (multipoint or broadcast) for communications among multiple users by allocating unique time slots to…
  34. time-division multiplexing (TDM) Digital multiplexing in which two or more apparently simultaneous channels are derived from a given frequency spectrum, i.e.
  35. time-division switching Switching of time-division multiplexed (TDM) channels by shifting bits between time slots in a TDM frame.
  36. time-domain reflectometer (TDR) An electronic instrument used to characterize and locate faults in metallic cables (e.g., twisted pair, coax).
  37. time-gated direct-sequence spread spectrum Direct-sequence spread spectrum where the transmitter is on only for a short fraction of a time interval.
  38. time-out A network parameter related to an enforced event designed to occur at the conclusion of a predetermined elapsed time. 2.
  39. time-sharing The interleaving of two or more independent processes on one functional unit. 2.
  40. time-variant value In cryptography, a value that changes with each transaction or with each message value. [After X9.19]
  41. timeliness See responsiveness.
  42. timing extraction Synonym timing recovery.
  43. timing jitter The short-term variations of the significant instants of a digital signal from their ideal positions in time.
  44. timing recovery The derivation of a timing signal from a received signal. Synonym timing extraction.
  45. timing signal The output of a clock. 2. A signal used to synchronize interconnected equipment.
  46. timing tracking accuracy A measure of the ability of a timing synchronization system to minimize the clock difference between a master clock and any slaved clock.
  47. TLM Abbreviation for telemetry.
  48. TLP Abbreviation for transmission level point.
  49. TM A mental technique used to promote relaxation, reduce stress, and improve quality of life. TM is the registered trademark of the Maharishi Foundation Ltd.
  50. TOD Abbreviation for time of day. See time of occurrence.
  51. Token See definition for: access token
  52. token passing A network access procedure in which a token passes from station to station and the only station allowed to transmit information is the station with the…
  53. token ring adapter A network interface card (NIC) designed to attach a client workstation to a token ring computer network and operate as a token-passing interface.
  54. token-bus network A bus network in which a token passing procedure is used.
  55. token-ring network See network topology.
  56. Tolerance A condition in which higher doses of a drug are required to produce the same effect achieved during initial use; often associated with physical dependence.
  57. tolerance field The region between two curves, such as circles or rectangles, used to specify the tolerance on component size and geometry. 2.
  58. toll call See long-distance call.
  59. toll center An office (or group of offices) within a city which generally handles the originating and incoming toll traffic for that city to or from other toll center…
  60. toll center area The areas served by a toll center, including the toll center city and the communities served by tributaries of the toll center. [47 CFR Pt.36-A]
  61. toll center toll office A toll office (as contrasted to a local office) in a toll center city. [47 CFR Pt.36-A]
  62. toll circuit A general term applied to interexchange trunks used primarily for toll traffic. [47 CFR Pt.36-A]
  63. toll connecting trunk A general classification of trunks carrying toll traffic and ordinarily extending between a local office and a toll office, except trunks classified as…
  64. toll diversion A system service feature by which users are denied the ability to place toll calls without the assistance of an attendant.
  65. Toll Free Number Portability The FCC Order that provided the customer with the ability to retain his toll free number and move or select carrier(s) of choice to service that same toll…
  66. Toll Free Service End-User Subscriber The entity which subscribes to Toll Free Service from the Toll Free Service Provider.
  67. toll office A central office used primarily for supervising and switching toll traffic. [47 CFR Pt.36-A]
  68. toll quality The voice quality resulting from the use of a nominal 4-kHz telephone channel. Note: Toll quality may be quantized in terms of a specified bit error ratio.
  69. toll restriction See classmark.
  70. toll switching trunk A trunk connecting one or more end offices to a toll center as the first stage of concentration for intertoll traffic.
  71. tone An electrically generated single-frequency sinusoidal oscillation. [T1.305-1990]
  72. tone diversity In a voice frequency telegraph (VFTG) transmission system, the use of two channels to carry the same information.
  73. tone signaling See dual-tone multifrequency signaling.
  74. TOOL Target of Opportunity Launch.
  75. top-level domain name In Internet addressing, a domain name identifying the highest hierarchical level in the geographical or organizational structure of the addressing system…
  76. Topography The shape of the Earth's surface; the relative position and elevations of natural and human-made features of an area.
  77. topology The geometric arrangement of a computer system. Common topologies include a bus (network topology in which nodes are connected to a single cable with…
  78. torn-tape relay An antiquated tape relay system in which the perforated tape is manually transferred by an operator to the appropriate outgoing transmitter.
  79. total channel noise The sum of random noise, intermodulation noise, and crosstalk. Note: Total channel noise does not include impulse noise because different techniques are…
  80. total harmonic distortion (THD) Of a signal, the ratio of (a) the sum of the powers of all harmonic frequencies above the fundamental frequency to (b) the power of the fundamental…
  81. Total Internal Reflection The trapping of light by refraction and reflection at critical angles inside a semiconductor device so that it cannot escape the device and must be…
  82. total line length In facsimile, the spot speed divided by the scanning line frequency. Note: The total line length may be greater than the length of the available line.
  83. touch panel See touch-sensitive.
  84. touch screen See touch-sensitive.
  85. touch tone dialing See dual-tone multifrequency (DTMF) signaling.
  86. touch-sensitive Pertaining to a device that allows a user to interact with a computer system by touching an area on the surface of the device with a finger, pencil, or…
  87. trace packet In a packet-switching network, a unique packet that causes a report of each stage of its progress to be sent to the network control center from each…
  88. trace program A computer program that performs a check on another computer program by exhibiting the sequence in which the instructions are executed and usually the…
  89. Traceability the property of a result of a measurement whereby it can be related to appropriate standards, generally international or national standards, through an…
  90. Track Each of the series of concentric rings contained on a hard drive platter.
  91. track density The number of tracks per unit length, measured in a direction perpendicular to the direction in which the tracks are read.
  92. trackball A ball that can be rotated about its center and that is used as an input device, e.g., to position a cursor. Synonym control ball.
  93. tracking error The deviation of a dependent variable with respect to a reference function.
  94. tracking mode An operational mode during which a system is operating within specified movement limits relative to a reference.
  95. tracking phase See tracking mode.
  96. Traffic The visitors to a web page or web site. Also refers to the number of visitors, hits, accesses etc. over a given period.
  97. Traffic Analysis A form of passive attack in which an intruder observes information about calls (although not necessarily the contents of the messages) and makes…
  98. traffic capacity The maximum traffic per unit of time that a given telecommunications system, subsystem, or device can carry under specified conditions.
  99. traffic encryption key (TEK) [A] key used to encrypt plain text or to superencrypt previously encrypted text and/or to decrypt cipher text. [INFOSEC-99]
  100. traffic engineering The determination of the numbers and kinds of circuits and quantities of related terminating and switching equipment required to meet anticipated traffic…