Telecommunications — page 19 of 85

Telecommunications terms

1801. CRYPTO A designation or marking which identifies classified operational keying material, and which indicates that this material requires special consideration…
1802. crypto key Deprecated term. See key.
1803. crypto-alarm [A] circuit or device that detects failures or aberrations in the logic or operation of crypto-equipment.
1804. crypto-algorithm [A] well-defined procedure or sequence of rules or steps, or a series of mathematical equations used to describe cryptographic processes such as…
1805. crypto-ancillary equipment Equipment designed specifically to facilitate efficient or reliable operation of crypto-equipment, without performing cryptographic functions itself.
1806. crypto-equipment See cryptographic equipment.
1807. crypto-ignition key (CIK) [A] device or electronic key used to unlock the secure mode of crypto-equipment. [INFOSEC-99]
1808. cryptochannel A complete system of crypto-communications between two or more holders. The basic unit for naval cryptographic communication.
1809. cryptographic 1. [The] art or science concerning the principles, means, and methods for rendering plain information unintelligible, and for restoring encrypted…
1810. cryptographic check value Information which is derived by performing a cryptographic transformation (see cryptography) on a data unit [7498-2].
1811. cryptographic component Hardware or firmware embodiment of the cryptographic logic. A cryptographic component may be a modular assembly, a printed wiring assembly, a…
1812. cryptographic equipment (crypto-equipment) Any device that embodies cryptographic logic or performs one or more cryptographic functions (e.g., key generation, encryption, and authentication).
1813. cryptographic hash A mathematical function that maps values from a large (or even very large) domain into a smaller range, and is (a) one-way in that it is computationally…
1814. Cryptographic Hash Function A function that maps a bit string of arbitrary length to a fixed length bit string.
1815. cryptographic information All information significantly descriptive of cryptographic techniques and processes or of cryptographic systems and equipment, or their functions and…
1816. cryptographic initialization [A] function used to set the state of a cryptographic logic prior to key generation, encryption, or other operating mode. [INFOSEC-99]
1817. Cryptographic Key A value used to control cryptographic operations, such as decryption, encryption, signature generation or signature verification.
1818. cryptographic key synchronization The ability for two nodes, that have cryptographically processed a transaction, to determine the identical transaction key. [After X9.24]
1819. cryptographic logic The embodiment of one (or more) crypto-algorithm(s) along with alarms, checks, and other processes essential to effective and secure performance of the…
1820. cryptographic randomization [A] function that randomly determines the transmit state of a cryptographic logic. [INFOSEC-99]
1821. cryptographic synchronization See cryptographic key synchronization.
1822. Cryptography Technique to scramble data to preserve confidentiality or authenticity.
1823. cryptologic Of or pertaining to cryptology. [JP 1-02]
1824. Cryptology The science that deals with hidden, disguised, or encrypted communications. It includes communications security and communications intelligence.
1825. cryptomaterial All material including documents, devices, equipment, and apparatus essential to the encryption, decryption, or authentication of telecommunications.
1826. cryptonet Stations holding a common key. [INFOSEC-99] Note: Activities that hold key for other than use, such as cryptologistic depots, are not cryptonet members…
1827. Cryptoperiod Time span during which each key setting remains in effect.
1828. cryptosecurity See communications security.
1829. cryptosynchronization [The] process by which a receiving decrypting cryptographic logic attains the same internal state as the transmitting encrypting logic. [INFOSEC-99]
1830. cryptosystem Associated COMSEC items interacting to provide a single means of encryption or decryption. [INFOSEC]
1831. crystal oscillator (XO) An oscillator in which the frequency is controlled by a piezoelectric crystal. Note 1: A crystal oscillator may require controlled temperature because its…
1832. CSMA Abbreviation for carrier sense multiple access.
1833. CSMA/CA Abbreviation for carrier sense multiple access with collision avoidance.
1834. CSMA/CD Abbreviation for carrier sense multiple access with collision detection.
1835. CSU (1) Computer Software Unit. (2) Communications System Utilization.
1836. CTX Abbreviation for Centrex® service.
1837. cumulative transit delay The total transit delay applicable for a data call obtained by summing the individual transit delays of all component portions of the data connection. [T1.
1838. current billing The combined amount of changes billed, excluding arrears. [47 CFR Pt.36-A]
1839. cursor A graphic pointer used with a mouse to point to a location on a terminal screen.
1840. curvature loss Synonym macrobend loss.
1841. curve-fitting compaction Data compaction accomplished by substituting an analytical expression for the data to be stored or transmitted.
1842. custom local area signaling service (CLASS) One of an identified group of network-provided enhanced services. Note: A CLASS group for a given network usually includes several enhanced service…
1843. Customer 1. The person or organization that purchases a Target of Evaluation [ITSEC]. 2. The corroboration that the source of data received is as claimed.
1844. customer access In an Integrated Services Digital Network (ISDN), the portion of the ISDN access that a network provider supplies to connect the customer, i.e.
1845. customer dialed charge traffic Traffic which is both (a) handled to completion through pulses generated by the customer and (b) for which either a message unit charge, bulk charge or…
1846. customer installation (CI) All telecommunication equipment and wiring on the customer side of the network interface. [T1.Rpt37-1994]
1847. customer management complex In network management, a complex that (a) is controlled by a customer and (b) is responsible for, and performs, maintenance for the customer installation.
1848. customer office terminal Termination equipment that (a) is located on the customer premises and (b) performs a function that may be integrated into the common carrier equipment.
1849. customer owned and maintained equipment (COAM) Deprecated term. See customer premises equipment.
1850. customer premises equipment (CPE) Terminal and associated equipment and inside wiring located at a subscriber's premises and connected with a carrier's communication channel(s) at the…
1851. customer premises wire The segment of wiring from the customer's side of the protector to the customer premises equipment. [47 CFR Pt.36-A]
1852. customer service unit (CSU) A device that provides an accessing arrangement at a user location to either switched or point-to-point, data-conditioned circuits at a specifically…
1853. customer-provided equipment Deprecated term. See customer premises equipment.
1854. Cut To divide a deck into two parts.
1855. cutback technique A destructive technique for determining certain optical fiber transmission characteristics, such as attenuation and bandwidth, by (a) performing the…
1856. cutoff attenuator A waveguide, of adjustable length, which varies the attenuation of signals passing through it.
1857. cutoff frequency The frequency either above which or below which the output of a circuit, such as a line, amplifier, or filter, is reduced to a specified level. 2.
1858. cutoff mode The highest order mode that will propagate in a given waveguide at a given frequency.
1859. cutoff wavelength The wavelength corresponding to the cutoff frequency. 2. In an uncabled single-mode optical fiber, the wavelength greater than which a particular…
1860. cutover The physical changing of circuits or lines from one configuration to another.
1861. CVSD Abbreviation for continuously variable slope delta modulation.
1862. CX Abbreviation for composite signaling.
1863. CX signaling Synonym composite signaling.
1864. cxr Abbreviation for carrier.
1865. cyber Loosely, a prefix referring to anything related to computers or networking. Note 1: For example, a "cyber cafe" is a coffee shop that offers computer…
1866. cyber security See information security.
1867. cybercommunity 1. The aggregate of participants in the use of a portion of cyberspace. 2. A special-interest group (SIG) of cyberspace participants.
1868. cybermall An electronic site shared by a number of commercial interests, and at which users can browse, shop, and place orders for the products listed at that site.
1869. cybernaut 1. One who uses the Internet. 2. Synonym Web surfer.
1870. Cyberspace An environment in which digitized information is distributed on networks of computers.
1871. Cybersquatting Registering domains related to other trademarks or brands in an attempt to cash in on the value created by said trademark or brand.
1872. cyclic distortion In telegraphy, distortion that (a) is periodic and (b) is not characteristic, not biased, and not fortuitous.
1873. cyclic redundancy check (CRC) An error-checking technique that helps ensure accurate transmission of digital data in a network.
1874. D Dust
1875. D channel In ISDN, the 16-kb/s segment of a 144-kb/s, full-duplex subscriber service channel that is subdivided into 2B+D channels, i.e.
1876. D layer See D region, ionosphere.
1877. D Region In solar-terrestrial terms, a daytime layer of the earth's ionosphere approximately 50 to 90 km in altitude.
1878. D-4 A framing standard for traditional time-division multiplexing, which standard describes user channels multiplexed onto a trunk that has been segmented…
1879. D-A Digital-to-Analog
1880. D-Star(D*) Synonym specific detectivity.
1881. D-type patch bay A patch bay designed for patching and monitoring of unbalanced data circuits at rates up to 1 Mb/s.
1882. D1 See channel bank.
1883. D2 Projective (interceptor) in the Hyper-Velocity Gun program.
1884. D3 See channel bank.
1885. D4 See channel bank.
1886. DACS Divert and Attitude Control System.
1887. daemon Abbreviation for disk and execution monitor. A procedure that is invoked without being called explicitly whenever an alteration, an addition, or a…
1888. DAMA Demand Assigned Multiple Access.
1889. Damping Resistance which reduces vibration by energy absorption.
1890. Damping ratio The ratio of the actual damping to the critical damping, critical damping being the minimum amount of damping which prevents free oscillatory vibration.
1891. dangling threat Set of properties about the external environment for which there is no corresponding vulnerability and therefore no implied risk. [INFOSEC-99]
1892. dangling vulnerability [A] set of properties about the internal environment for which there is no corresponding threat and, therefore, no implied risk. [INFOSEC-99]
1893. dark current The external current that, under specified biasing conditions, flows in a photoconductive detector when there is no incident radiation.
1894. DAT An acronym for Digital Audio Tape, which some backup systems utilize as a storage medium.
1895. data A representation of facts, concepts, or instructions in a formalized manner suitable for communication, interpretation, or processing by humans or by…
1896. data access arrangement In public switched telephone networks, a single item or group of items at the customer side of the network interface for data transmission purposes…
1897. data aggregation [In security,] the compilation of unclassified individual data systems and data elements resulting in the totality of the information being classified.
1898. data attribute A characteristic of a data element such as length, value, or method of representation.
1899. data authentication A process used to verify data integrity, e.g., verification that data received are identical to data sent, or verification that a program is not infected…
1900. data bank A set of data related to a given subject and organized in such a way that it can be consulted by users. 2.