Telecommunications terms starting with L

291 terms

  1. L-pad A pad composed of two discrete components, one series component and one shunt component.
  2. label The FDA approved label is the official description of a drug product which includes indication (what the drug is used for); who should take it; adverse…
  3. label bureau A computer or server that supplies content labels or Web-site ratings. Synonym rating server. [Bahorsky]
  4. labeled channel In integrated services digital networks, (ISDN), a time-ordered set of all block payloads that have labels containing the same information, i.e.
  5. labeled interface structure In integrated services digital networks (ISDN), an interface structure that provides telecommunications services and signaling by means of labeled…
  6. labeled multiplexing In integrated services digital networks (ISDN), multiplexing by concatenation of the blocks of the channels that have different identifiers in their…
  7. labeled statistical channel In integrated services digital networks (ISDN), a labeled channel in which the block payloads or the duration of each successive block is random.
  8. laboratory attack Use of sophisticated signal recovery equipment in a laboratory environment to recover information from data storage media. [INFOSEC-99]
  9. Lambert's cosine law See Lambertian source.
  10. Lambert's emission law Synonym Lambertian source.
  11. Lambertian radiator See Lambertian source.
  12. Lambertian reflector See Lambertian source.
  13. Lambertian source An optical source that obeys Lambert's cosine law, i.e., that has an intensity directly proportional to the cosine of the angle from which it is viewed.
  14. LAN Local Area Network.
  15. LAN application (software) An application software package specifically designed to operate in a local-area-network environment.
  16. LAN operating system See network operating system.
  17. land line An informal name for conventional telephone facilities. Note: Land lines include conventional twisted-pair lines, carrier facilities, and microwave radio…
  18. land mobile service A mobile service between base stations and land mobile stations, or between land mobile stations. [NTIA] [RR] [47CFR]
  19. land mobile station A mobile station in the land mobile service capable of surface movement within the geographical limits of a country or continent. [NTIA] [RR] [47CFR]
  20. land mobile-satellite service A mobile-satellite service in which mobile Earth stations are located on land. [NTIA] [RR]
  21. land station A station in the mobile service not intended to be used while in motion. [NTIA] [RR] [47CFR]
  22. landline Traditional wired phone service.
  23. Landscape Mode The image is represented on the page or monitor such that the width is greater than the height.
  24. language A set of characters, conventions, and rules that is used for conveying information.
  25. language processor A program that performs tasks, such as translating and interpreting, required for processing a specified programming language.
  26. language-binding API left
  27. language-independent service specification A specification that facilitates the management and development of consistent language-binding standards [POSIX.0]
  28. LAP-B The Data Link Layer protocol as specified by ITU-T Recommendation X.25 (1989).
  29. LAP-D Abbreviation for link access procedure D. A link protocol used in ISDN.
  30. large prime factors Specially constructed large prime numbers, viz., p1, p2, q1, and q2, each > 2100, where p1|p-1, p2|p+1, q1|q-1, and q2|q+1, where p and q are the private…
  31. laser (LAY-zer) A device that concentrates light into an intense, narrow beam used to cut or destroy tissue.
  32. laser chirp An abrupt change of the center wavelength of a laser, caused by laser instability.
  33. laser diode Synonym injection laser diode.
  34. laser disk See optical disk.
  35. laser intelligence (LASINT) Technical and geolocation intelligence derived from laser systems; a subcategory of electro-optical intelligence. [JP 1-02]
  36. laser medium Synonym active laser medium.
  37. lasing See laser.
  38. lasing threshold The lowest excitation level at which laser output is dominated by stimulated emission rather than by spontaneous emission.
  39. LASINT Acronym for laser intelligence.
  40. last number redial Synonym automatic redial.
  41. last-in first-out (LIFO) A queuing discipline in which entities in a queue leave in the reverse order of the sequence in which they arrive.
  42. LATA Acronym for local access and transport area.
  43. lateral offset loss In fiber optics, a loss of optical power at a splice or connector, caused by a lateral, i.e.
  44. Lattice The regular periodic arrangement of atoms or molecules in a crystal of semiconductor material.
  45. launch angle The angle, with respect to the normal, at which a light ray emerges from a surface. 2.
  46. launch numerical aperture (LNA) The numerical aperture of an optical system used to couple (launch) power into an optical fiber.
  47. launching fiber An optical fiber used in conjunction with a source to excite the modes of another fiber in a particular fashion.
  48. lay length In communications cables--including fiber-optic cables--having the transmission media wrapped helically around a central member, the longitudinal distance…
  49. layer A thematic set of spatial data described and stored in an ArcStorm database or a LIBRARIAN map library.
  50. layer entity An active element within a layer. [T1.630-1999]
  51. layer function A part of the activity of the layer entities. [T1.627-1993]
  52. layer interface The boundary between two adjacent layers in the model. [T1.110-1987]
  53. layer service A capability of the (N) layer and the layers beneath it, which is provided to (N + 1) layer entities, at the boundary between the (N) layer and the (N +…
  54. layer service elements An indivisible component of the layer service made visible to the service user via layer service primitives. [T1.110-1987]
  55. layer service primitives A means for specifying in detail the adjacent layer interactions. [T1.110-1987]
  56. layer user data Data transferred between corresponding entities on behalf of the upper layer or layer management entities for which they are providing services. [T1.
  57. layered protocol The protocol reference model defined by layered structures based on and using the terminology of ITU-T Recommendations X.200 and X.210.
  58. layered system A system in which components are grouped, i.e., layered, in a hierarchical arrangement, such that lower layers provide functions and services that support…
  59. LBO Abbreviation for line buildout. Synonym building out.
  60. LCD Abbreviation for liquid crystal display.
  61. LDAP A protocol for accessing directory information. LDAP or Lightweight Directory Access Protocol is used by browsers and email clients to look up email…
  62. LDM Abbreviation for limited distance modem.
  63. leaky bucket counter A counter that is incremented by one each time an event occurs and is decremented by a fixed value periodically. [T1.218-1991]
  64. leaky mode In an optical fiber, a mode having a field that decays monotonically for a finite distance in the transverse direction but becomes oscillatory everywhere…
  65. leaky ray In an optical fiber, a ray for which geometric optics would predict total internal reflection at the boundary between the core and the cladding, but which…
  66. leap second An occasional adjustment of one second, added to, or subtracted from, Coordinated Universal Time (UTC) to bring it into approximate synchronism with UT1…
  67. leased circuit Dedicated common-carrier facilities and channel equipment used by a network to furnish exclusive private line service to a specific user or group of users.
  68. Least Privilege This principle requires that each subject in a system be granted the most restrictive set of privileges (or lowest clearance) needed for the performance…
  69. least significant bit In a binary code, the bit or bit position that is assigned to, or represents, the smallest quantity or increment that can be represented by the code.
  70. least-time principle Synonym Fermat's principle.
  71. LEC Abbreviation for local exchange carrier.
  72. LED (1) Low Endoatmospheric Defense. (2) Light Emitting Diode.
  73. left-hand (anti-clockwise) polarized wave An elliptically or circularly polarized wave, in which the electric field vector, observed in the fixed plane, normal to the direction of propagation…
  74. Leg A side post in tunnel timbering.
  75. length indicator (LI) A six-bit field that defines message length and that is used to differentiate between message signal units, link status signal units, and fill-in signal…
  76. LEO Low Earth Orbit.
  77. LERG Assigne The SP responsible for default routing functions associated with a pooled NXX code.
  78. LERG™ Routing Guide The Telcordia® LERG™ Routing Guide contains information about the local routing data obtained from the BIRRDS.
  79. Level The number of values used in a card counting system. A level one counting system only uses +1 and -1, but a level two system would use +1, +2, -1 and -2…
  80. level alignment The adjustment of transmission levels of single links and of links in tandem to prevent problems such as overloading of transmission subsystems.
  81. level of protection [The] extent to which protective measures, techniques, and procedures must be applied to information systems (IS) and networks based on risk, threat…
  82. LF (1) Landing Force. (2) Low Frequency. 165
  83. library A collection of cells, usually bacteria or yeast, that have been transformed with recombinant vectors carrying DNA inserts from a single species.
  84. life cycle The sequence of events from a given developmental stage in one generation to the same stage in the following generation.
  85. LIFO Last In, First Out. See also "FIFO". A LIFO is usually called a "stack".
  86. Light A pane of glass; a window, or a compartment of a window.
  87. light pen A stylus, usually hand-held, that contains a photodetector or light source, and that allows interaction with a computer through a specially designed…
  88. light valve Synonym optical switch.
  89. Light-emitting diode (LED) This very energy efficient lighting technology uses 80 to 90% less energy than conventional lights.
  90. lightguide See optical fiber.
  91. lightness The brightness of an area subjectively judged relative to the brightness of a similarly illuminated area that appears to be white or highly transmitting.
  92. lightning down-conductor In a lightning protection subsystem, the conductor connecting the air terminal or overhead ground wire to the earth electrode subsystem.
  93. lightning protection subsystem All of the components used to protect a facility from the effects of lightning.
  94. limited protection A form of short-term communications security applied to the electromagnetic or acoustic transmission of unclassified information that warrants a degree of…
  95. limited-protection voice equipment Equipment that provides limited security for unclassified voice communications.
  96. limiter A device in which the voltage or some other characteristic of the output signal is automatically prevented from exceeding a specified value.
  97. limiter circuit A circuit of nonlinear elements that restricts the electrical excursion of a variable in accordance with specified criteria.
  98. limiting Any process by which a specified characteristic (usually amplitude) of the output of a device is prevented from exceeding a predetermined value.
  99. limits of interference In radio transmission, the maximum permissible interference as specified in recommendations of the International Special Committee on Radio Interference…
  100. line See Groove