Telecommunications — page 48 of 85

Telecommunications terms

4701. minimum ACL An ACL that contains only the required entries [POSIX.6].
4702. minimum bend radius The radius below which an optical fiber or fiber-optic cable should not be bent.
4703. minimum discernable signal (MDS) See threshold.
4704. minimum picture interval The minimum time between the television pictures that have been selected for encoding. Note: ITU-T Recommendation H.
4705. minimum standards left
4706. minimum-dispersion slope See zero-dispersion slope.
4707. minimum-dispersion wavelength Synonym zero-dispersion wavelength.
4708. minimum-dispersion window The window of an optical fiber at which material dispersion is very small. Note 1: In silica-based fibers, the minimum-dispersion window occurs at a…
4709. minimum-loss window Of an optical fiber, the transmission window at which the attenuation coefficient is at or near the theoretical (quantum-limited) minimum.
4710. minutes-of-use A unit of measurement expressed as either holding time or conversation time. [47 CFR Pt.36-A]
4711. minutes-of-use-kilometers The product of (a) the number of minutes-of-use-and (b) the average route kilometers of circuits involved. [47 CFR Pt.36-A]
4712. MIP Maintenance Index Page (Navy ILS term).
4713. mirroring The duplication of data for purposes of backup or to distribute Internet or network traffic among several servers with identical data.
4714. MIS Management information systems.
4715. misalignment loss See angular misalignment loss, gap loss, lateral offset loss.
4716. misdelivered block A block received by a user other than the one intended by the message source.
4717. misdelivered frame A frame transferred from a source user to a destination user other than the intended destination user.
4718. mission bit stream Synonym payload.
4719. Mistracking The phenomenon that occurs when the path followed by the read head of the recorder does not correspond to the location of the recorded track on the…
4720. mixer 1. A nonlinear analog circuit or device that accepts as its input two different frequencies (signals) and presents at its output (a) a signal equal in…
4721. mixing See heterodyne, mixer.
4722. MJU Abbreviation for multipoint junction unit. Equipment used by the service provider to perform the bridging functions for multipoint service. [T1.Rpt39-1995]
4723. MLP(multilevel precedence) compatibility mode An ANSI Tl.224 operation mode that uses the MLP Channel to transfer data. ANSI Tl.224 data sent on the MLP channel is broadcast to all other ANSI T1.
4724. MLPP Abbreviation for multilevel precedence and preemption.
4725. MM patch bay A patching facility designed for patching and monitoring of digital data circuits at rates exceeding 3 Mb/s.
4726. mobile Earth station An Earth station in the mobile-satellite service intended to be used while in motion or during halts at unspecified points. [NTIA] [RR] 2.
4727. mobile service A radiocommunication service between mobile and land stations, or between mobile stations. [NTIA] [RR] [47CFR]
4728. mobile services switching center (MSC) In an automatic cellular mobile system, the interface between the radio system and the public switched telephone network.
4729. mobile station A station in the mobile service intended to be used while in motion or during halts at unspecified points. [NTIA] [RR] [47CFR] 2.
4730. mobile station international ISDN number A dialable number and, in the context of this document, a 10-digit NANP (North American Numbering Plan) directory number assigned to address a wireless…
4731. mobile-satellite service A radiocommunication service: between mobile earth stations and one or more space stations, or between space stations used by this service; or between…
4732. modal dispersion Incorrect synonym for multimode distortion.
4733. modal distortion Synonym multimode distortion.
4734. modal distribution In an optical waveguide operating at a given wavelength, the number of modes supported, and their propagation time differences.
4735. modal loss In an open waveguide, such as an optical fiber, a loss of energy on the part of an electromagnetic wave due to obstacles outside the waveguide, abrupt…
4736. modal noise Noise generated in an optical fiber system by the combination of mode-dependent optical losses and fluctuation in the distribution of optical energy among…
4737. mode In a frequency distribution, the class having the greatest frequency.
4738. mode [identification friend or foe] The number or letter referring to the specific pulse spacing of the signals transmitted by an interrogator. [JP1]
4739. mode coupling In an electromagnetic waveguide, the exchange of power among modes. Note: In a multimode optical fiber, mode coupling reaches statistical equilibrium, i.e.
4740. mode field diameter (MFD) An expression of distribution of the irradiance, i.e., the optical power, across the end face of a single-mode fiber.
4741. mode filter A device used to select, reject, or attenuate a certain mode or modes.
4742. mode mixer Synonym mode scrambler.
4743. Mode of Operation An algorithm for the cryptographic transformation of data that features a symmetric key block cipher algorithm.
4744. mode partition noise In an optical communications link, phase jitter of the signal caused by the combined effects of mode hopping in the optical source and intramodal…
4745. mode scrambler A device for inducing mode coupling in an optical fiber. 2. A device composed of one or more optical fibers in which strong mode coupling occurs.
4746. mode stripper See cladding mode stripper.
4747. mode volume The number of bound modes that an optical fiber is capable of supporting. Note: The mode volume M is approximately given by V2/2 and (V2/2)[g/(g+2)]…
4748. Modem A device that allows a computer system to transmit data over telephone or cable lines.
4749. modem patch A method of electrically interconnecting circuits by using back-to-back modems.
4750. moderated conference An electronic conference in which participants exchange computer messages via a moderator who may accept, modify, or reject them. [2382-pt.35]
4751. moderator In computer conferencing, a person who receives the prospective messages from conference attendees and may accept, modify, or reject them. [2382-pt.
4752. modification detection Synonym manipulation detection.
4753. modification detection code Synonym manipulation detection code.
4754. Modification of Final Judgment (MFJ) The 1982 antitrust suit settlement agreement ("Consent Decree") entered into by the United States Department of Justice and the American Telephone and…
4755. modified AMI code Abbreviation for modified alternate mark inversion code. A T-carrier AMI line code in which bipolar violations may be deliberately inserted to maintain…
4756. modular Pertaining to the design concept in which interchangeable units are used to create a functional end product.
4757. modular jack A device that conforms to the Code of Federal Regulations, Title 47, part 68, which defines the size and configuration of all units that are permitted for…
4758. Modulation Modulation is the method by which a high-frequency digital signal is grafted onto a lower-frequency analog wave, so that digital packets are able to ride…
4759. modulation factor In amplitude modulation, the ratio of the peak variation actually used, to the maximum design variation in a given type of modulation.
4760. modulation index In angle modulation, the ratio of the frequency deviation of the modulated signal to the frequency of a sinusoidal modulating signal.
4761. modulation rate The rate at which a carrier is varied to represent the information in a digital signal.
4762. modulation suppression In the reception of an amplitude-modulated signal, an apparent reduction in the depth of modulation of a wanted signal, caused by the presence, at the…
4763. modulator A device that imposes a signal on a carrier.
4764. modulator-demodulator (modem) See modem.
4765. module The smallest self-contained, environmentally protected structure housing interconnected photovoltaic cells and providing a single dc electrical output…
4766. modulo-2 addition Binary addition with no carry. [After X9.8]
4767. monitor (MAH-nih-ter) In medicine, to regularly watch and check a person or condition to see if there is any change.
4768. monitor black level Relative to video, the luminance displayed on a monitor by a signal at reference black level. [After SMPTE]
4769. monitor jack A jack used to access communications circuits to observe signal conditions without interrupting the services.
4770. monitor key A key used to access communications circuits to observe signal conditions without interrupting the services.
4771. monitor window An interval during which an entity performs the monitoring function at the direction of a service control function. [T1.667-1999]
4772. monitoring The act of listening, carrying out surveillance on, and/or recording the emissions of one's own or allied forces for the purposes of maintaining and…
4773. monochromatic In optics, pertaining to a single wavelength of electromagnetic radiation or to a single color.
4774. monochromator In optics, an instrument for isolating narrow portions of the spectrum.
4775. monomode optical fiber Synonym single-mode optical fiber.
4776. Months to Exhaust (MTE) A calculation that is used by SPs to document the need for an additional code or block as follows:
4777. more (M) bit A bit used to indicate that more packets in sequence are to be expected by the terminating endpoint. [T1.
4778. mosquito noise In a video display, distortion sometimes seen around the edges of moving objects, and characterized by moving artifacts around edges and/or by blotchy…
4779. most significant bit In a binary code, the bit or bit position that is assigned to, or represents, the largest quantity or increment that can be represented by the code.
4780. motion compensation Interframe coding that (a) is used to compress motion of video images and (b) uses an algorithm to examine a sequence of image frames to measure the…
4781. motion response degradation The deterioration of motion video quality, resulting in a loss of perceived spatiotemporal resolution.
4782. motion video In video systems, temporally varying visual imagery intended to communicate or to convey movement or change.
4783. motion-related artifacts Distortion of motion video potentially observable by the viewer. In some instances, the distortion becomes more observable with increased motion.
4784. mouse A hand-controlled hardware device for interacting with a computer terminal or entering data from a digitizer.
4785. MP3 A standard wave file format (with a ".wav" file extension) for digitally encoded and compresses music files (similar to the format used for CD music…
4786. MPILIB (Multiple Precision Integer Library) This is the common name for the set of RSA routines used in PGP 2.3a and previous, as well as the international versions of PGP.
4787. MTA Abbreviation for message transfer agent.
4788. MTBF Mean Time Between Failures.
4789. MTBO Abbreviation for mean time between outages.
4790. MTSR Abbreviation for mean time to service restoral.
4791. MTTR Mean Time To Repair.
4792. MTU Military Training Unit (ILS term).
4793. mu-law (µ-law) See mu-law (-law) algorithm.
4794. mu-law (µ-law) algorithm A standard analog signal compression algorithm, used in digital communications systems of the North American digital hierarchy, to optimize, i.e.
4795. mudbox Equipment that is sufficiently rugged to withstand adverse environments. Note: A mudbox is expected to operate unsheltered on the ground.
4796. MUF Abbreviation for maximum usable frequency.
4797. muldem Acronym for multiplexer/ demultiplexer.
4798. Multi Carrier Toll Free Service The capability resulting from the portability order that enabled multiple carriers to use the LEC Features such as Percent Allocation in the SMS/800 to…
4799. multi-center exchange An exchange area in which are located two or more local central office buildings or wire centers. [47 CFR Pt.36-A]
4800. multi-class Comprising or containing information of more than one security class [CESG].