FOA CFOT 2026 STUDY GUIDE QUESTIONS AND ANSWERS
GUARANTEE A+
✔✔Fiber Identifier - ✔✔Device that clamps onto a fiber and couples light from the fiber
by bending, identifying the fiber (amongst others in a bundle, for example) by detecting
high speed traffic of an operating link or 2kHz tone injected by a test source.
✔✔Fiber Tracer - ✔✔An instrument that couples visible light into the fiber to allow visual
checking of continuity and tracing for correct connections.
✔✔Ferrule - ✔✔Precision tube which holds a fiber for alignment for interconnection.
Typically made from ceramics and is white in color.
✔✔Fiber Amplifier - ✔✔Uses erbium or other doped fibers and pump lasers to increase
signal output power without electronic conversion.
✔✔Excess Loss - ✔✔Amount of light lost in a coupler, beyond what is typical in the
splitting to multiple output fibers.
✔✔ESCON - ✔✔IBM standard for connecting peripherals to a computer over fiber
optics.
✔✔Equilibrium Modal Distribution (EMD) - ✔✔Steady state modal distribution in
multimode fiber, achieved some distance from the source, where the relative power in
the modes becomes stable with increasing distance.
✔✔End Finish - ✔✔Quality of the end surface of a fiber prepared for splicing or
terminated in a connector.
✔✔Edge-emitting Diode (E-LED) - ✔✔An LED that emits from the edge of the
semiconductor chip, producing higher power and narrower spectral width.
✔✔Dispersion - ✔✔Temporal spreading of a pulse in an optical waveguide. May be
caused by modal or chromatic effects.
✔✔Distributed Feedback Laser (DFB) - ✔✔Used for high speed and long distance
transmitters.
✔✔Detector - ✔✔Photodiode that converts optical signals into electrical signals.
✔✔Decibel (dB) - ✔✔Unit of measurement of optical power which indicates relative
power on a logarithmic scale. dB = 10 log
✔✔dBm - ✔✔Optical power referenced to 1 miliwatt.
, ✔✔Coarse Wavelength Division Multiplexing (CWDM) - ✔✔Use of lasers spaced widely
over the range of 1260nm to 1670 nm.
✔✔Cutoff Wavelength - ✔✔The wavelength beyond which singlemode fiber only
supports one mode of propagation is called a what?
✔✔Cutback Method - ✔✔Technique for measuring loss of bare fiber by comparing the
sources initial coupled power to the power measured at the end of a long length of fiber.
✔✔Coupler - ✔✔Device that splits or combines light from more than one fiber.
✔✔Core - ✔✔The center of the optical fiber through which light is transmitted.
✔✔Connector - ✔✔A device that provides for a demountable connection between two
fibers (or fiber and active device). Also provides protection for the fiber.
✔✔Cladding - ✔✔Lower fractive index optical coating over the core of fiber that "traps"
light into the core.
✔✔Chromatic Dispersion - ✔✔Temporal spreading of a pulse in an optical waveguide
caused by the wavelength dependence of the velocities of light.
✔✔Buffer - ✔✔A protective coating applied directly on the fiber.
✔✔Bit - ✔✔An electrical or optical pulse that carries information.
✔✔Bit-Error Rate (BER) - ✔✔Fraction of data bits transmitted that are received in error.
✔✔Bending Loss / Microbending Loss - ✔✔Loss in fiber caused by stress on the fiber
bet around a restrictive radius.
✔✔Bandwidth - ✔✔Range of signal frequencies or bit rate within which a fiber optic
component, link or network will operate. The maximum speed that data can be
transmitted over the link.
✔✔Backscattering - ✔✔The scattering of light in a fiber back toward the source, used to
make OTDR measurements.
✔✔Attenuation / Attenuator - ✔✔Reduction in optical power as it passes along a fiber is
called ___________, usually expressed in dB. Devices that do this purposefully are
called _____________
GUARANTEE A+
✔✔Fiber Identifier - ✔✔Device that clamps onto a fiber and couples light from the fiber
by bending, identifying the fiber (amongst others in a bundle, for example) by detecting
high speed traffic of an operating link or 2kHz tone injected by a test source.
✔✔Fiber Tracer - ✔✔An instrument that couples visible light into the fiber to allow visual
checking of continuity and tracing for correct connections.
✔✔Ferrule - ✔✔Precision tube which holds a fiber for alignment for interconnection.
Typically made from ceramics and is white in color.
✔✔Fiber Amplifier - ✔✔Uses erbium or other doped fibers and pump lasers to increase
signal output power without electronic conversion.
✔✔Excess Loss - ✔✔Amount of light lost in a coupler, beyond what is typical in the
splitting to multiple output fibers.
✔✔ESCON - ✔✔IBM standard for connecting peripherals to a computer over fiber
optics.
✔✔Equilibrium Modal Distribution (EMD) - ✔✔Steady state modal distribution in
multimode fiber, achieved some distance from the source, where the relative power in
the modes becomes stable with increasing distance.
✔✔End Finish - ✔✔Quality of the end surface of a fiber prepared for splicing or
terminated in a connector.
✔✔Edge-emitting Diode (E-LED) - ✔✔An LED that emits from the edge of the
semiconductor chip, producing higher power and narrower spectral width.
✔✔Dispersion - ✔✔Temporal spreading of a pulse in an optical waveguide. May be
caused by modal or chromatic effects.
✔✔Distributed Feedback Laser (DFB) - ✔✔Used for high speed and long distance
transmitters.
✔✔Detector - ✔✔Photodiode that converts optical signals into electrical signals.
✔✔Decibel (dB) - ✔✔Unit of measurement of optical power which indicates relative
power on a logarithmic scale. dB = 10 log
✔✔dBm - ✔✔Optical power referenced to 1 miliwatt.
, ✔✔Coarse Wavelength Division Multiplexing (CWDM) - ✔✔Use of lasers spaced widely
over the range of 1260nm to 1670 nm.
✔✔Cutoff Wavelength - ✔✔The wavelength beyond which singlemode fiber only
supports one mode of propagation is called a what?
✔✔Cutback Method - ✔✔Technique for measuring loss of bare fiber by comparing the
sources initial coupled power to the power measured at the end of a long length of fiber.
✔✔Coupler - ✔✔Device that splits or combines light from more than one fiber.
✔✔Core - ✔✔The center of the optical fiber through which light is transmitted.
✔✔Connector - ✔✔A device that provides for a demountable connection between two
fibers (or fiber and active device). Also provides protection for the fiber.
✔✔Cladding - ✔✔Lower fractive index optical coating over the core of fiber that "traps"
light into the core.
✔✔Chromatic Dispersion - ✔✔Temporal spreading of a pulse in an optical waveguide
caused by the wavelength dependence of the velocities of light.
✔✔Buffer - ✔✔A protective coating applied directly on the fiber.
✔✔Bit - ✔✔An electrical or optical pulse that carries information.
✔✔Bit-Error Rate (BER) - ✔✔Fraction of data bits transmitted that are received in error.
✔✔Bending Loss / Microbending Loss - ✔✔Loss in fiber caused by stress on the fiber
bet around a restrictive radius.
✔✔Bandwidth - ✔✔Range of signal frequencies or bit rate within which a fiber optic
component, link or network will operate. The maximum speed that data can be
transmitted over the link.
✔✔Backscattering - ✔✔The scattering of light in a fiber back toward the source, used to
make OTDR measurements.
✔✔Attenuation / Attenuator - ✔✔Reduction in optical power as it passes along a fiber is
called ___________, usually expressed in dB. Devices that do this purposefully are
called _____________
