WGU C172 - Chapter 3: Physical Layer Cabling Fiber Optics
questions with verified answers
3 commonly used wavelengths in today's fiber-optic systems? Ans✓✓✓-
Multimode fiber (850 and 1310 nm), Single-mode fiber (1310 and 1550 nm), Fiber
to home/business (1600-1625 nm)
Absorption Ans✓✓✓-Second loss factor, a composite of light interaction with the
atomic structure of the glass. Involves the conversion of optical power to heat.
Backbone Ans✓✓✓-Main fiber distribution. The primary path for data traffic to
and from destinations and sources in the campus network.
Chromatic Dispersion Ans✓✓✓-The broadening of a pulse due to different
propagation velocities of the spectral components of the light pulse. Present in
both single-mode and multimode fibers.
Cladding Ans✓✓✓-Material surrounding the fiber optic core, which must have a
lower index of refraction to keep the light in the core.
Dense Wavelength Division Multiplex (DWDM) Ans✓✓✓-Incorporates the
propagation of several wavelengths in the 1550 nm range for a single fiber.
Dispersion (Pulse Broadening) Ans✓✓✓-Second of the two key distance-limiting
parameters in a fiber-optic transmission system. It is when the light pulse spreads
out in time as it propagates along the fiber strand, broadening the pulse.
Dispersion Compensating Fiber Ans✓✓✓-Acts as an equalizer, cancelling
dispersion effects and yielding close to zero dispersion in the 1550 nm region.
, Distributed Feedback Laser (DFB) Ans✓✓✓-A more stable laser suitable for use in
DWDM systems. Uses techniques that provide optical feedback in the laser cavity,
enhancing output stability, which produces a narrow and more stable spectral
width.
Fiber Bragg Grating Ans✓✓✓-A short strand of modified fiber that changes the
index of refraction and minimizes inter symbol interference.
Fiber Cross-Connect Ans✓✓✓-Optical patch panel used to interconnect fiber
cables.
Fiber Optic Attenuation Ans✓✓✓-Loss of power introduced by the fiber. This loss
accumulates as the light is propagated through the fiber strand. Expressed in
dB/km.
Fusion Splicing Ans✓✓✓-A long-term method where two fibers are fused or
welded together.
Gigabit Interface Converter (GBIC) Ans✓✓✓-Hot-swappable transceiver that is
used for transmitting and receiving higher-speed signals over fiber-optic lines.
Graded-index Fiber Ans✓✓✓-The index of refraction is gradually varied with a
parabolic profile to overcome the pulse-dispersion problem.
Index-Matching Gel Ans✓✓✓-A jellylike substance that has an index of refraction
much closer to glass than to air.
questions with verified answers
3 commonly used wavelengths in today's fiber-optic systems? Ans✓✓✓-
Multimode fiber (850 and 1310 nm), Single-mode fiber (1310 and 1550 nm), Fiber
to home/business (1600-1625 nm)
Absorption Ans✓✓✓-Second loss factor, a composite of light interaction with the
atomic structure of the glass. Involves the conversion of optical power to heat.
Backbone Ans✓✓✓-Main fiber distribution. The primary path for data traffic to
and from destinations and sources in the campus network.
Chromatic Dispersion Ans✓✓✓-The broadening of a pulse due to different
propagation velocities of the spectral components of the light pulse. Present in
both single-mode and multimode fibers.
Cladding Ans✓✓✓-Material surrounding the fiber optic core, which must have a
lower index of refraction to keep the light in the core.
Dense Wavelength Division Multiplex (DWDM) Ans✓✓✓-Incorporates the
propagation of several wavelengths in the 1550 nm range for a single fiber.
Dispersion (Pulse Broadening) Ans✓✓✓-Second of the two key distance-limiting
parameters in a fiber-optic transmission system. It is when the light pulse spreads
out in time as it propagates along the fiber strand, broadening the pulse.
Dispersion Compensating Fiber Ans✓✓✓-Acts as an equalizer, cancelling
dispersion effects and yielding close to zero dispersion in the 1550 nm region.
, Distributed Feedback Laser (DFB) Ans✓✓✓-A more stable laser suitable for use in
DWDM systems. Uses techniques that provide optical feedback in the laser cavity,
enhancing output stability, which produces a narrow and more stable spectral
width.
Fiber Bragg Grating Ans✓✓✓-A short strand of modified fiber that changes the
index of refraction and minimizes inter symbol interference.
Fiber Cross-Connect Ans✓✓✓-Optical patch panel used to interconnect fiber
cables.
Fiber Optic Attenuation Ans✓✓✓-Loss of power introduced by the fiber. This loss
accumulates as the light is propagated through the fiber strand. Expressed in
dB/km.
Fusion Splicing Ans✓✓✓-A long-term method where two fibers are fused or
welded together.
Gigabit Interface Converter (GBIC) Ans✓✓✓-Hot-swappable transceiver that is
used for transmitting and receiving higher-speed signals over fiber-optic lines.
Graded-index Fiber Ans✓✓✓-The index of refraction is gradually varied with a
parabolic profile to overcome the pulse-dispersion problem.
Index-Matching Gel Ans✓✓✓-A jellylike substance that has an index of refraction
much closer to glass than to air.
