• A
• B
• C
• D
• E
• F
• G
• H
• I
• J
• K
• L
• M
• N
• O
• P
• Q
• R
• S
• T
• U
• V
• W
• X
• Y
• Z

• A
• Absorption

  The absorbing of light energy and conversion to heat, caused by impurities in the glass
• Acceptance Angle

  The largest angle where the fiber core can accept incoming light, and usually measured from the fiber axis
• Access Network

  A component within a wider telecommunication network that connects individuals and business users
• Adapter

  A component within a wider telecommunication network that connects individuals and business usersA coA mechanical device used to align and join fiber optic connectors
• Adapter Sleeve

  A mechanical fixture contained in an adapter that aligns and holds the terminated fiber connectors; also known as a split sleeve
• Aerial Plant

  A mechanical fixture contained in an adapter that aligns and holds the terminated fiber connectors; also known as a split sleeveCables that is suspended in the air on telephone and utility poles
• Angled Physical Contact (APC)

  A style of fiber optic ferrule polishing with a 5˚-15˚ angle on the ferrule tip for the purpose of minimizing backreflection
• Angular Misalignment

  The largest angle where the fiber core can accept incoming light, and usually measured from the fiber axisThe angle misalignment of fiber optic connectors, and causes attenuation
• Aramid Yarn

  A type of yarn inside a fiber optic cable that provides support, protection and tensile strength
• Armor

  A metallic protective layer inside a fiber optic cable that provides extra protection of the fiber
• Armored Cable

  A type of fiber optic cable that includes armor
• Attenuation

  The reduction of optical power between two points and normally expressed in decibels (dB)
• Attenuation Coefficient

  The attenuation with respect to a specific unit length, usually decibels per kilometer (db/km)
• Attenuation Meter

  A device used to measure attenuation in fiber optic cables, connectors, and systems
• Attenuator

  A passive device that reduces the amplitude of a light signal
• Average Power

  The average power signal over a period of time
• Axis

  The center of an optical fiber

• B
• Backbone

  A main portion of a telecommunication network that connects relatively distant points or regions
• Backbone Cabling

  The cabling in inter- and intra-buildings that connects entrance facilities, equipment rooms and telecommunication closets
• Backreflection

  Light that is reflected and travels back to the origin source; also known as return loss
• Backscattering

  Scattering of light and heads in the direction of the original source
• Bandwidth

  The capacity of an optical fiber in terms of its ability to carry information, and measured in megahertz per kilometer (MHz-km) or gigahertz per kilometer (GHz-km)
• Bend Radius

  The maximum radius from bending a fiber without significant attenuation or breakage of the fiber
• Bending Loss

  The attenuation or loss in an optical fiber caused by bending
• Bragg Scattering

  Scattering of light that is caused by changes in the refractive index of a material
• Breakout

  Separation of individual fibers or buffer tubes in a fiber optic cable for the purpose of splicing or installing fiber optic connectors
• Breakout Cable

  A type of fiber optic cable that contains fibers with individual jackets and then all individual jackets surrounded by one common cable jacket
• Bundle

  A group of individual fibers assembled in an unit
• Buffer

  The protective layer inside a fiber optic cable that surrounds the fiber cladding that provides protection and mechanical isolation; also known as buffer tubes, buffer coating or coating

• C
• Cable

  An assembly of optical fibers along with other materials for protecting the fiber, enclosed for protective covering
• Cable Assembly

  The assembling of fiber optic connectors into fiber optic cables, either in the form of patch cords (connectors on both ends) or pigtails (connector on one end)
• Central Member

  The center component of a fiber optic cable that can serve as a strength member and therefore also known as central strength member
• Channel

  A communications path
• Channel Spacing

  The allocation of bandwidth to channels
• Chromatic Dispersion

  Dispersion caused by different wavelengths in the light signal travelling at different speeds, expressed in picoseconds per kilometer per nanometer, and the sum of material and waveguide dispersion
• Cladding

  A layer of glass surround the fiber core in a fiber optic cable, and together with the fiber core make up an optical waveguide
• Cleave

  A process in fiber optic cable assembly that separating an optical fiber by a controlled fracture of the glass, for the purpose of obtaining a fiber end that is flat, smooth, and perpendicular to the fiber axis
• Cleaver

  A precision tool that breaks the fiber to produce a flat end for polishing or splicing
• Composite Cable

  A cable consisting of both fiber and copper; also known as hybrid cable
• Concentricity

  The measurement of how centered the core is within the cladding
• Conduit

  Pipes or tubes where fiber optic cables can be pulled or housed
• Connector

  A mechanical device mounted on an end of a fiber optic cable for the purpose of attaching and decoupling the fiber to another source
• Connectorization

  The preparation of an end of a fiber and connector assembling; also referred as termination
• Containerized Data Center

  Data center that is housed in a shipping container, opposed to a building
• Core

  The center of the optical fiber that transmit light
• Coupler

  A device that combines light into one fiber or splits light into more than one fiber
• Coupling

  The transfer of light into or out of an optical fiber
• Crimper

  A tool that crimps a fiber optic connector to the fibers in the cable to provide additional mechanical strength
• Critical Angle

  The smallest angle of light ray with respect to the normal that can guide light path
• Cross-connect

  A facility enabling the termination of cables as well as their interconnection or cross-connection with other cabling or equipment. Also known as a distributor
• Cutoff Wavelength

  The wavelength beyond which singlemode fiber only supports one mode of propagation

• D
• Decibel (dB)

  A measuring unit used to measure optical power
• Dielectric

  A material such as fiber that is non-metallic and non-conductive
• Dispersion

  The spreading of light pulses as it travels along the fiber
• Dispersion Compensation

  The reduction of dispersion in a fiber
• Ducting

  A conduit for placing and protecting fiber optic cable
• Duplex Cable

  A type of cable construction where two cables are attached to form one cable

• E
• Eccentricity

  A measurement of the amount by which the core is not placed centrally in the cladding
• Electromagnetic Interference (EMI)

  The interference of signal transmission because of radiation; optical fibers are not susceptible to electromagnetic interferences
• Enclosure

  A cabinet for enclosing cable terminations and splices
• End Finish

  The quality of the end surface of a fiber that is needed for splicing or terminating a connector
• Entrance Facility

  The part in a building which serves as an entrance for network cables
• Epoxy

  A thermosetting resin used in fiber optic cable assemblies to secure the fiber with the connector ferrule
• Equipment Room

  The centralized room that houses telecommunications equipment in a building
• ESCON

  An IBM standard for connecting peripherals to a computer over fiber optics
• Extrinsic Loss

  Attenuation caused by an external source extrinsic to an optical transmission system

• F
• Fanout

  A breakout style multifiber cable designed for ease of connectorization for intra or interbuilding requirements
• Ferrule

  The alignment tube that is attached to the ends of a fiber optic connector, and are generally made of zirconia, alumina, or plastic
• Fiber

  A thin filament of glass or plastic that consists of a core and a cladding
• Fiber Optics

  The use of fiber to guide light transmission for communications or lighting
• Fiber Optics

  The use of fiber to guide light transmission for communications or lighting
• Fiber Stripper

  A tool that is used to remove the buffer coating of a fiber optic cable
• Fiber Tracer

  An instrument that traces fiber connections and allows for visual checking of continuity
• Frequency

  The number of cycles per a unit of time, where 1 hertz equals I cycle per second
• Fresnel Reflection

  Light reflection that occurs from the surface when there is a sudden change in the refractive index as at the end of a fiber
• Fusion Splice

  A splicing technique that permanently joins the fiber ends by applying heat to fuse or melt the ends together, forming a continuous single fiber
• Fusion Splicer

  An instrument that performs fusion splice

• G
• Gigahertz (GHz)

  A unit of frequency that equals one billion cycles per second
• Graded Index Fiber

  A fiber where the characteristics of the center of the fiber core has the highest refractive index, and decreases towards the cladding

• H
• Hertz (Hz)

  A unit of frequency that equals one cycle per second
• Horizontal Cabling

  The portion of cabling that connect the floor distributor to the work area telecommunications outlets

• I
• Index Matching Fluid

  The portion of cabling that connect the floor distributor to the work area telecommunications outletsA fluid with a refractive index close to glass for reducing reflections caused by refractive-index differences of materials
• Index of Refraction

  A measure of the speed of light and is a ratio of the speed of light in a material compared to its speed in free space; also referred as the refractive index
• Injection Loss

  Attenuation caused by the insertion of a component such as a fiber optic connector or splice; also known as insertion loss
• Insertion Loss

  Attenuation caused by the insertion of a component such as a fiber optic connector or splice; also known as injection loss
• Interbuilding Backbone

  The backbone cabling between buildings
• Intrabuilding Backbone

  The backbone cabling within a building
• Intrinsic Loss

  Attenuation caused within the fiber

• J
• Jacket

  The outer layer protective coating of a fiber optic cable
• Jacket Stripper

  A cutter for stripping cable jackets
• Jumper

  A fiber optic cable that is connectorized at both ends of the cables; also known as a patch cord

• K
• Kevlar

  A trademark of aramid yarn used inside fiber optic cables for support, protection, and tensile strength
• Keying

  A trademark of aramid yarn used inside fiber optic cables for support, protection, and tensile strengthThe mechanical feature of a connector system which guarantees correct orientation of a connection or prevents the connection to a jack or optical fiber

• L
• Lapping Film

  Film that is used to polish the end of the connector ferrules; also referred as polishing paper or polishing film
• Laser

  An acronym for light amplification by stimulated emission of radiation, which is a device that products high-intensity, directional, monochromatic beam of light
• Laser Diode

  A laser made of semiconductor materials used to transmit light into optical fibers
• Light Emitting Diode (LED)

  A semiconductor device that produces light with a wide range of wavelengths in response to an electrical signal
• Local Area Network (LAN)

  A communications network in small physical areas, such as a building or a group of buildings
• Loose Tube Cable

  A fiber optic cable design where protective tubes surrounds optical fibers within the outer cable jacket
• Loss Budget

  A budget of the total losses (attenuation) acceptable in a fiber optic system
• Low Smoke Zero Halogen (LSZH)

  A cable jacket rating that has features of limited smoke and no halogens when exposed to heat

• M
• Macrobend

  The bending of a fiber optic cable that could be visually seen by the human eye
• Main Cross-connect (MC)

  A cross-connect for fist level backbone cables, entrance cables, and equipment cables
• Mechanical Splice

  The joining of optical fibers via mechanical methods, rather than via fusion splicing
• Megahertz (MHz)

  A unit of frequency that equals one million cycles per second
• Metropolitan Area Network (MAN)

  A communications network, larger than a LAN, may consists of several LANs and extend to the size of a metropolitan area
• Micro

  A prefix for a millionth
• Microbend

  The small, microscopic bend of a fiber optic cable caused during the manufacturing process
• Micrometer (μm)

  A unit of distance that equals one millionth of a meter; also referred as a micron
• Micron (μm)

  A unit of distance that equals one millionth of a meter; also referred as a micrometer
• Microscope

  A device used to inspect the end surface of a connector
• Modal Dispersion

  A type of dispersion in multimode fibers where light pulses spread along the length of a fiber
• Mode

  Light transmission paths in a fiber where the number of modes is determined by the numerical aperture and the core diameter; two broad types are singlemode and multimode
• Mode Field Diameter (MFD)

  The diameter of one mode of light in singlemode fiber
• Monomode Fiber

  A type of fiber that transmit light in one single mode, and has a smaller fiber core than multimode fiber; also referred as singlemode fiber
• Multi-Fiber Cable

  A fiber optic cable that contains more than one fiber
• Multimode Fiber (MMF)

  A type of fiber that transmit lights with more than one mode, and has a bigger fiber core than singlemode fiber
• Multiplexing

  The transmission of different signals in a single fiber

• N
• Nanometer (nm)

  A unit of one billionth of a meter
• National Electrical Code (NEC)

  A US standard for flammability of cable and wiring in buildings
• Node

  A connection point, either a redistribution point or an end point for data transmissions. In general, a node has programmed or engineered capability to recognize, process, and forward transmissions to other nodes.
• Numerical Aperture (NA)

  A measure that expresses the light gathering ability of a fiber

• O
• OM5

  OM5 is a new type of optical fiber specified by ISO/IEC 11801 in Oct-2016. This wideband multimode fiber utilizes a wide range of wavelengths from 850 to 953nm with Short Wave Division Multiplexing (SWDM) to reach 400G transmission
• Optical Fiber

  A thin filament of glass or plastic that consists of a core and a cladding
• Optical Fiber Non-conductive Plenum (OFNP)

  A cable jacket rating that is non-conductive and used in plenum applications; they have the highest fire retardant rating compared to OFNR and LSZH
• Optical Fiber Non-conductive Riser (OFNR)

  A cable jacket rating that is suitable for use in riser applications and they are engineered to prevent fire from spreading from floor to floor within buildings
• Optical Time Domain Reflectometer (OTDR)

  An instrument that measures the transmission characteristics of optical fiber by sending a series of short pulses of light down the fiber and providing a graphic representation of the backscattered light
• Outlets

  The sockets provided in the work location of a structured cabling system
• Overfilled Launch

  A condition for launching light into the fiber where the incoming light has a spot size and numerical aperture larger than accepted by the fiber, filling all modes in the fiber

• P
• Passive Optical Network (PON)

  A point-to-multipoint optical communications network
• Patch Cord

  A fiber optic cable that is connectorized at both ends of the cables; also known as a jumper
• Patch Panel

  A hardware that connects backbone cabling to an arrangement of connectors to form cross-connections and interconnections
• Physical Contact (PC)

  A style of fiber optic ferrule polishing where the fiber is polished to a smooth curve and the adjoining fibers comes into physical contact with no air gaps
• Pigtail

  A fiber optic cable that is connectorized at one end only
• Plenum

  The air handling space of a building, such as in raised floors or drop-ceiling tiles
• Point-to-Point (P2P)

  The air handling space of a building, such as in raised floors or drop-ceiling tilesA direct communications connection between two specific locations
• Polarization

  The alignment of the perpendicular electrical and magnetic fields that make up a lightwave
• Polyethylene (PE)

  A plastic material found in the jackets of outside plant fiber optic cables
• Polyvinyl-Chloride (PVC)

  A plastic material found in the jackets of flame retardant fiber optic cables, ideally deployed in indoor applications
• Polyvinyldifluoride (PVDF)

  A material found in the jacket of optical fiber non-conductive plenum (OFNP) cables
• Preform

  A large diameter glass rod where the fiber is constructed

• Q

• R
• Raceway

  Any distribution method designed for holding cables (i.e. conduit, metal or plastic trunking, cable trays, etc.)
• Refractive Index

  A measure of the speed of light and is a ratio of the speed of light in a material compared to its speed in free space; also referred as the index of refraction
• Repeater

  A device used to regenerate an optical signal to prevent attenuation and used in long-distance fiber optic links
• Return Loss

  Light that is reflected and travels back to the origin source; also known as backreflection
• Riser

  The cable paths between floors in a building

• S
• Scattering

  A glass property that causes light to deflect from the fiber and contribute to intrinsic attenuation
• Server

  A computer in a network that provides different services to client computers in the same network
• Signal to Noise Ratio

  The ratio of signal level to background noise, measured in decibels
• Simplex cable

  A type of cable construction that consists of a single fiber core
• Singlemode Fiber (SMF)

  A type of fiber that transmit light in one single mode, and has a smaller fiber core than multimode fiber; also referred as monomode fiber
• Splice

  A method of joining two optical fiber ends
• Splice Closure

  A closure container used to hold and protect splice trays
• Splice Trays

  A hardware container used to manage, hold and protect spliced fibers
• Split Sleeve

  A mechanical fixture contained in an adapter that aligns and holds the terminated fiber connectors; also known as an adapter sleeve
• Splitter

  A device that takes signal from one fiber and splits it into several other fibers
• Step Index Fiber

  A fiber with a refractive index that changes abruptly between the core and the cladding
• Storage Area Network (SAN)

  A high speed network or subnetwork of shared storage devices
• Strength Member

  Part of a fiber optic cable that provides extra protection and tensile strength, and may consist of steel strands and aramid yarn

• T
• Telecommunications Closet

  A closet for housing telecommunications equipment, cables and cross-connects
• Termination

  The preparation of an end of a fiber and connector assembling; also referred as connectorization
• Tight Buffered Cable

  A type of fiber optic cable where each fiber is tightly buffered by a 900-micron coating for easy handling and connectorization
• Topology

  The layout of a communications network
• Total Internal Reflection (TIR)

  Reflection of light as it travels and approaches materials of different refractive indices at an angle greater than the critical angle
• Transmitter

  A device that acts as both a receiver and transceiver
• Trunk cable

  Any fiber optic cable that is capable of supporting multiple users or devices from one point to another
• Tunable Laser

  A laser that can change its frequency over a given range

• U

• V

• W
• Waveguide Dispersion

  Dispersion caused by light travelling at different speeds in singlemode fibers
• Wavelength

  The distance an electromagnetic wave travels during the time it takes to oscillate through one complete cycle, and measured in nanometers (nm)
• Wide Area Network (WAN)

  A large communications network similar to a smaller local area network (LAN)

• X

• Y

• Z
• Zero-Dispersion Wavelength

  Wavelength with minimum chromatic dispersion of a singlemode optical fiber