Telecommunications — page 52 of 85

Telecommunications terms

5101. normal mode (presentation layer) The mode of operation of the Presentation Layer, which provides the full facilities of the presentation service. [T1.208-1989]
5102. normal resolution still image A still image transmitted in the ANSI Tl.314 video stream encoded to the same resolution as the previous motion video (i.e.
5103. normal routing The routing of a given signaling traffic stream under normal conditions (in the absence of failures). [T1.226-1992]
5104. normal/alarm (N/A) state bit A bit used in signaling packets to transfer information on alarm status across a permanent virtual circuit in the direction of transmission from the…
5105. normalized frequency (V) In an optical fiber, a dimensionless quantity, V, given by where a is the core radius, λ is the wavelength in vacuum, n1 is the maximum refractive index…
5106. North American Number Plan (NANP) A plan for the allocation of unique 10-digit address numbers. The numbers consists of a 3-digit area (numbering plan area) code, a 3-digit office code…
5107. North American Numbering Plan Numbering Resource Utilization/Forecasting (NRUF) Report The NANPA gathers forecast and utilization information to monitor and project exhaust in individual NPAs/area codes as well as in the NANP overall.
5108. not-ready condition At the data terminal equipment/data circuit-terminating equipment (DTE/DCE) interface, a steady-state condition that indicates that the DCE is not ready…
5109. Notarization 1. A method of changing a key-enciphering key so as to confirm the identities of the originator and the ultimate recipient. [After X9.8] 2.
5110. notch In a relatively wide band of frequencies, not necessarily of uniform amplitude, a narrow band of frequencies having relatively low amplitudes.
5111. notched filter Synonym band-stop filter.
5112. notched noise Noise from which a narrow band of frequencies has been removed. Note: Notched noise is usually used for testing devices or circuits.
5113. Np Abbreviation for neper.
5114. NPA Abbreviation for numbering plan area.
5115. NPA Code Relief NPA code relief refers to an activity that must be performed when and NPA nears exhaust of its 792 NXX capacity.
5116. NPA Relief Date The date by which the NPA is introduced and routing of normal commercial traffic begins.
5117. NRI Abbreviation for net radio interface.
5118. NRZ Abbreviation for non-return-to-zero.
5119. NRZ-M Synonym non-return-to-zero mark.
5120. NS/EP telecommunications Abbreviation for National Security or Emergency Preparedness telecommunications.
5121. NSA (National Security Agency) The NSA is the official cryptologic organization of the U.S. government. need-to-know: 1.
5122. NSFnet The high-speed national network that superseded ARPA Net as the framework of the Internet.
5123. NTI Northern Telecom Incorporated.
5124. NTN Abbreviation for network terminal number.
5125. NTSC standard Abbreviation for National Television Standards Committee standard. The North American standard (525-line interlaced raster-scanned video) for the…
5126. Nuclear Hardness A quantitative description of the resistance of a system or component to malfunction (temporary and permanent) and/or degraded performance induced by a…
5127. null The null type has one value, the null reference, represented by the literal null, which is formed from ASCII characters.
5128. null character (NUL) In transmission systems, a control character (a) that is used to accomplish media-fill stuffing or a time-fill stuffing in storage device or in a data…
5129. number portability A term used to describe the capability of individuals, businesses and organizations to retain their existing telephone number(s) and the same quality of…
5130. numbering plan area (NPA) 1. A defined geographic area identified by a unique three- digit code used in the North American Number Plan Area. [T1.207-1998] [T1.
5131. numerical aperture (NA) The sine of the vertex angle of the largest cone of meridional rays that can enter or leave an optical system or element, multiplied by the refractive…
5132. numerical aperture loss A loss of optical power that occurs at a splice or a pair of mated connectors when the numerical aperture of the "transmitting" fiber exceeds that of the…
5133. NVIS Near Vertical Incidence System (SINCGARS term).
5134. NXX code In the North American direct distance dialing numbering plan, a central office code of three digits that designates a particular central office or a given…
5135. Nyquist interval The maximum time interval between equally spaced samples of a signal that will enable the signal waveform to be completely determined.
5136. Nyquist rate The reciprocal of the Nyquist interval, i.e., the minimum theoretical sampling rate that fully describes a given signal, i.e.
5137. Nyquist's theorem A theorem, developed by H. Nyquist, which states that an analog signal waveform may be uniquely reconstructed, without error, from samples taken at equal…
5138. object An entity such as a file, folder, shared folder, printer, or Active Directory object, described by a distinct, named set of attributes.
5139. object persistence In a video display, distortion wherein the entirety of some object (or objects) that appeared in a previous frame (and that should no longer appear)…
5140. object retention In a video display, distortion in which a fragment of an object that appeared in a previous frame (and should no longer appear) remains in the current and…
5141. object reuse 1. Reassignment and re-use of a storage medium containing one or more objects after ensuring no residual data remains on the storage medium.
5142. Object-Oriented A software development approach that organizes software as a collection of objects containing both data structure and behavior.
5143. obsolete In cryptography, pertaining to the state of a key that must no longer be used either to transmit information from the originator or to process received…
5144. obsolete date In encryption, the date and time when a key becomes obsolete. [After X9.17]
5145. OC Operations Center.
5146. OCC Abbreviation for other common carrier.
5147. Occupancy Indicates whether the property to which the loan application relates will be the owner's principal dwelling.
5148. occupied bandwidth The width of a frequency band such that, below the lower and above the upper frequency limits, the mean powers emitted are each equal to a specified…
5149. oceanographic data interrogating station A station in the maritime mobile service the emissions of which are used to initiate, modify or terminate functions of equipment directly associated with…
5150. oceanographic data station A station in the maritime mobile service located on a ship, buoy, or other sensor platform the emissions of which are used for transmission of…
5151. OCN An Operating Company Number (OCN) is a four place alphanumeric code that uniquely identifies providers of local telecommunications service.
5152. OCR Optical Character Reader.
5153. octet A byte of eight binary digits usually operated upon as an entity.
5154. octet alignment The configuration of a field composed of an integral number of octets. Note: If the field is not divisible by eight, bits (usually zeros) are added to…
5155. OD Optical Disk (PATRIOT).
5156. odd parity See parity, parity check.
5157. odd-even check Synonym parity check.
5158. OFC Abbreviation for optical fiber, conductive. Note: OFC is the designation given by the National Fire Protection Association (NFPA) to interior fiber-optic…
5159. OFCP Abbreviation for optical fiber, conductive, plenum. Note: OFCP is the designation given by the National Fire Protection Association (NFPA) to interior…
5160. OFCR Abbreviation for optical fiber, conductive, riser. Note: OFCR is the designation given by the National Fire Protection Association (NFPA) to interior…
5161. Off the Shelf Procurement of existing system or equipment without an RDT&E program or with minor development to make the system suitable for DoD needs.
5162. off-axis optical system An optical system in which the optical axis of the aperture is not coincident with the mechanical center of the aperture.
5163. off-hook In telephony, the condition that exists when an operational telephone instrument or other user instrument is in use, i.e., during dialing or communicating.
5164. off-hook service Synonym hotline.
5165. off-hook signal In telephony, of a circuit, a signal indicating seizure, request for service, or a busy condition.
5166. off-line Pertaining to the operation of a functional unit when not under the direct control of the system with which it is associated.
5167. off-line authentication certificate A particular form of authentication information binding an entity to a cryptographic key, certified by a trusted authority, which may be used for…
5168. off-line cryptosystem [A] cryptosystem in which encryption and decryption are performed independently of the transmission and reception functions. [INFOSEC-99]
5169. off-line recovery The process of recovering nonprotected message traffic by use of an off-line processor or central processing unit.
5170. Off-Line Storage Electronic records stored or archived on removable disc (optical, compact, etc.
5171. off-net calling The process by which telephone calls that originate or pass through private switching systems in transmission networks are extended to stations in a…
5172. off-premises extension (OPX) An extension telephone, PBX station, or key system station located on property that is not contiguous with that on which the main telephone, PBX, or key…
5173. off-the-air In radio communications systems, pertaining to a station that is completely shut down, i.e.
5174. off-the-air monitoring In radio net operations, the listening, by the net-control station, to the transmissions of stations in the net, particularly to check the quality of…
5175. offered load The total load submitted to a trunk group. This value may be corrected for retrials during the engineering process. [T1.Rpt 11-1991]
5176. office classification Prior to divestiture, numbers that were assigned to offices according to their hierarchical function in the U.S. public switched telephone network.
5177. offset You offset an options or futures position by taking a second position in a contract with identical terms, buying if you sold initially or selling if you…
5178. offset encryption The process of encryption by using a key that has been offset. [After X9.28]
5179. offset track In information assurance, a track written at a nonstandard position on a diskette, as part of a method of copy protection. [2382-pt.8]
5180. OFN Abbreviation for optical fiber, nonconductive. Note: OFN is the designation given by the National Fire Protection Association (NFPA) to interior…
5181. OFNP Abbreviation for optical fiber, nonconductive, plenum. Note: OFNP is the designation given by the National Fire Protection Association (NFPA) to interior…
5182. OFNR Abbreviation for optical fiber, nonconductive, riser. Note: OFNR is the designation given by the National Fire Protection Association (NFPA) to interior…
5183. oligarchically synchronized network A synchronized network in which the timing of all clocks is controlled by a selected few clocks.
5184. Omega A term used to describe vertical motion in the atmosphere. The "omega equation" used in numerical weather models is composed of two terms, the…
5185. omnidirectional antenna An antenna that has a radiation pattern that is nondirectional in azimuth. Note: The vertical radiation pattern may be of any shape.
5186. omnidirectional range station A radionavigation land station in the aeronautical radionavigation service providing direct indication of the bearing (omnibearing) of that station from…
5187. on-board communication station A low-powered mobile station in the maritime mobile service intended for use for internal communications on board a ship, or between a ship and its…
5188. on-hook In telephony, the condition that exists when an operational telephone, or other user instrument, is not in use.
5189. on-hook signal In telephony, of a circuit, a signal indicating a disconnect, unanswered call, or an idle condition.
5190. on-hook state A state in which the customer installation (CI) presents a high-resistance path at the network interface. [T1.Rpt37-1994]
5191. On-Line A unit that is operational, not dormant, but is not participating with on-going functions.
5192. on-line authentication certificate A particular form of authentication information, certified by a trusted authority, which may be used for authentication following direct interaction with…
5193. on-line cryptosystem [A] cryptosystem in which encryption and decryption are performed in association with the transmitting and receiving functions. [INFOSEC-99]
5194. on-premises extension An extension telephone, PBX station, or key system station located on property that is contiguous with that on which the main telephone, PBX, or key…
5195. on-premises wiring Customer-owned metallic or optical-fiber communications transmission lines, installed within or between buildings.
5196. on-screen button A pictorial representation of a pushbutton on a display screen, which functions as a binary control, for example, on/off. [T1.232-1996]
5197. on-the-air In radio communications systems, pertaining to a station that is transmitting a carrier, whether or not the carrier is modulated. 2.
5198. ONA Abbreviation for open network architecture.
5199. one-part code Code in which plain text elements and their accompanying code groups are arranged in alphabetical, numerical, or other systematic order, so one listing…
5200. one-time cryptosystem Cryptosystem employing key used only once. [INFOSEC-99]