NCTI FIBER INSTALL & ACTIVATION QUESTIONS &
ANSWERS
Which standards organization is considered the creator of the world's most recognized
communications standards, known as recommendations?
The International Telecommunications Union (ITU)
In which component in a fiber-optics communication system do changes to the intensity
of the optical signal occur?
The optical transmitter
What is one drawback of using Fabry-Perot (F-P) lasers in high-speed data (HSD)
networks?
The emission of several discrete wavelengths or side modes
Why are laser diodes most effective when coupled to single-mode fiber (SMF)?
The laser diode has a small spectral width, efficient coupling, and fast modulation
speeds
What is the main factor in determining the sensitivity of an optical receiver?
Noise
Which diode is most commonly used in optical receivers because it is inexpensive and
can be operated from a standard power supply?
Positive-intrinsic-negative (PIN) diode
What does the multiplication process, which amplifies the electrical signal in an APD,
introduce into the electrical output of an optical detector?
Noise
Which type of diode requires a higher voltage power supply and more complex circuitry
than PIN diodes?
APD
, Which of the following is the ratio of electrical output power from the detector to the
optical input power, expressed by amperes or volts per watt of optical input power?
Responsivity
Where would you expect Fresnel reflections to occur in a fiber-optic network?
At connections and mechanical splices where the signal source is entering or exiting the
cable
Chromatic dispersion is a combination of which two dispersions?
Material and waveguide dispersion
When defining the optical transport region of SMF, specifying which of the following is
more accurate, technically correct and critical to use?
Mode field diameter (MFD)
What is the current standardization outside diameter (OD) of the cladding of SMF?
125 µm, with an accuracy of ±1 µm
What do diameter differences between spliced fibers look like on an OTDR?
A gain in one direction and a high loss in the opposite direction
Besides protection, what else must the coating on an optical fiber do?
Function over a wide temperature range
What is involved when monitoring the status of optical nodes?
The use of a node transponder that continuously monitors several critical functions
What is an advantage of a digital return system?
The amount of fiber required in the network can be greatly reduced by using dense
wavelength division multiplexing (DWDM) digital return transmitters in hub-to-headend
architectures
Broadband cable operators provide customers with HSD connections to the Internet
through their HFC networks using what standard?
DOCSIS
ANSWERS
Which standards organization is considered the creator of the world's most recognized
communications standards, known as recommendations?
The International Telecommunications Union (ITU)
In which component in a fiber-optics communication system do changes to the intensity
of the optical signal occur?
The optical transmitter
What is one drawback of using Fabry-Perot (F-P) lasers in high-speed data (HSD)
networks?
The emission of several discrete wavelengths or side modes
Why are laser diodes most effective when coupled to single-mode fiber (SMF)?
The laser diode has a small spectral width, efficient coupling, and fast modulation
speeds
What is the main factor in determining the sensitivity of an optical receiver?
Noise
Which diode is most commonly used in optical receivers because it is inexpensive and
can be operated from a standard power supply?
Positive-intrinsic-negative (PIN) diode
What does the multiplication process, which amplifies the electrical signal in an APD,
introduce into the electrical output of an optical detector?
Noise
Which type of diode requires a higher voltage power supply and more complex circuitry
than PIN diodes?
APD
, Which of the following is the ratio of electrical output power from the detector to the
optical input power, expressed by amperes or volts per watt of optical input power?
Responsivity
Where would you expect Fresnel reflections to occur in a fiber-optic network?
At connections and mechanical splices where the signal source is entering or exiting the
cable
Chromatic dispersion is a combination of which two dispersions?
Material and waveguide dispersion
When defining the optical transport region of SMF, specifying which of the following is
more accurate, technically correct and critical to use?
Mode field diameter (MFD)
What is the current standardization outside diameter (OD) of the cladding of SMF?
125 µm, with an accuracy of ±1 µm
What do diameter differences between spliced fibers look like on an OTDR?
A gain in one direction and a high loss in the opposite direction
Besides protection, what else must the coating on an optical fiber do?
Function over a wide temperature range
What is involved when monitoring the status of optical nodes?
The use of a node transponder that continuously monitors several critical functions
What is an advantage of a digital return system?
The amount of fiber required in the network can be greatly reduced by using dense
wavelength division multiplexing (DWDM) digital return transmitters in hub-to-headend
architectures
Broadband cable operators provide customers with HSD connections to the Internet
through their HFC networks using what standard?
DOCSIS
