FIBER INSTALLATION AND ACTIVATION QUESTIONS AND
ANSWERS
Which standards organization is considered to be the creator of the world's most
recognized communications standards, know as "recommendations"? - Answers- ITU
In which component in a fiber-optics communication system do changes to the intensity
of the optical signal occur? - Answers- The optical transmitter
What is the drawback of using F-P lasers in HSD networks? - Answers- The emission
of a number of discrete wavelengths or side modes.
Why are laser diodes most effective when coupled to a singlemode fiber? - Answers-
It's high coupled power, directionality. and speed.
What are the factors that contribute to an optical receiver's sensitivity? - Answers-
Noise, responsitivity, response time, linear response, back reflection, and optical
detector material.
What is a characteristic of light in a laser beam? - Answers- The laser beam consists of
a limited range of wavelengths (monochromatic), with all light waves in phase (coherent
light).
Monitoring the status of optical nodes - Answers- Involves the use of a node
transponder that continuously monitors a number of critical functions.
Digital return path transmissions - Answers- Use dense wavelength division
multiplexing (DWDM) digital return transmitters in hub-to-headend architectures.
What is channel bonding? - Answers- A 3.0 revision to Data Over Cable Service
Interface Specification (DOCSIS) that significantly increases upstream and downstream
transport data rates.
What is MPEG? - Answers- A universally accepted standard for digital television, first
released in 1992.
Which of the following is true about optical nodes? - Answers- They contain four main
sections: the optical reciever, the RF amplifier module, the reverse optical transmitter,
and the DC power supply.
What product based on the DOCSIS defines the protocols for IP telephony over HFC
networks? - Answers- PacketCable
In a centralized server VOD architecture, - Answers- The number of servers needed for
video content storage is smaller than in distributed server architecture.
, Which of the following statements about local ad insertion is true? - Answers- Local ad
insertion is performed usually by a video server.
In regard to providing high-speed data (HSD) service, - Answers- The CMTS can
provide a data transfer rate up to 38Mbps using 256-QAM in a single 6MHz channel.
Which of the following is true about the SONET transmission standard? - Answers-
SONET is the Nor
th American standard used for telephony applications.
Why was the zero-dispersion point in single-mode fiber moved to 1,550 nm? - Answers-
To take advantage of the low intrinsic absorption and lower attenuation at 1550nm
single-mode fiber.
What type of single-mode fiber is intended for FTTH installations? - Answers- The ITU-
T G.657 BiF
What is a PIN diode? - Answers- An optical detector with current flow that is linear to
the intensity of light photons, with one electron/hole pair created for every absorbed
photon until saturation.
What does the amplification process in an APD introduce into the electrical output of an
optical detector? - Answers- Noise
What functions does the detector in an optical receiver perform? - Answers- Conversion
of an optical carrier to an electrical signal, and demodulation of the modulated optical
carrier.
What happens if the optical signal exceeds the maximum specified input power into a
photodetector? - Answers- Nonlinear operation resulting in distortion, data errors, and
signal loss.What are the primary causes of intrinsic loss in SMF? - Answers- Material
absorption and Rayleigh scattering
The phenomenon, total internal reflection, is what enables an optical fiber to guide light.
What characteristic of optical fiber causes total internal reflection? - Answers- The
difference in refractive indexes, between cladding, and core,causes light to be reflected
off the cladding and back into the core along the optical fiber.
Where would you expect Fresnel reflections to occur in a fiber-optic network? -
Answers- At connections and mechanical splices where the signal source is entering or
exiting the cable.
Chromatic dispersion is a combination of which two dispersions? - Answers- Material
and waveguide dispersion.
ANSWERS
Which standards organization is considered to be the creator of the world's most
recognized communications standards, know as "recommendations"? - Answers- ITU
In which component in a fiber-optics communication system do changes to the intensity
of the optical signal occur? - Answers- The optical transmitter
What is the drawback of using F-P lasers in HSD networks? - Answers- The emission
of a number of discrete wavelengths or side modes.
Why are laser diodes most effective when coupled to a singlemode fiber? - Answers-
It's high coupled power, directionality. and speed.
What are the factors that contribute to an optical receiver's sensitivity? - Answers-
Noise, responsitivity, response time, linear response, back reflection, and optical
detector material.
What is a characteristic of light in a laser beam? - Answers- The laser beam consists of
a limited range of wavelengths (monochromatic), with all light waves in phase (coherent
light).
Monitoring the status of optical nodes - Answers- Involves the use of a node
transponder that continuously monitors a number of critical functions.
Digital return path transmissions - Answers- Use dense wavelength division
multiplexing (DWDM) digital return transmitters in hub-to-headend architectures.
What is channel bonding? - Answers- A 3.0 revision to Data Over Cable Service
Interface Specification (DOCSIS) that significantly increases upstream and downstream
transport data rates.
What is MPEG? - Answers- A universally accepted standard for digital television, first
released in 1992.
Which of the following is true about optical nodes? - Answers- They contain four main
sections: the optical reciever, the RF amplifier module, the reverse optical transmitter,
and the DC power supply.
What product based on the DOCSIS defines the protocols for IP telephony over HFC
networks? - Answers- PacketCable
In a centralized server VOD architecture, - Answers- The number of servers needed for
video content storage is smaller than in distributed server architecture.
, Which of the following statements about local ad insertion is true? - Answers- Local ad
insertion is performed usually by a video server.
In regard to providing high-speed data (HSD) service, - Answers- The CMTS can
provide a data transfer rate up to 38Mbps using 256-QAM in a single 6MHz channel.
Which of the following is true about the SONET transmission standard? - Answers-
SONET is the Nor
th American standard used for telephony applications.
Why was the zero-dispersion point in single-mode fiber moved to 1,550 nm? - Answers-
To take advantage of the low intrinsic absorption and lower attenuation at 1550nm
single-mode fiber.
What type of single-mode fiber is intended for FTTH installations? - Answers- The ITU-
T G.657 BiF
What is a PIN diode? - Answers- An optical detector with current flow that is linear to
the intensity of light photons, with one electron/hole pair created for every absorbed
photon until saturation.
What does the amplification process in an APD introduce into the electrical output of an
optical detector? - Answers- Noise
What functions does the detector in an optical receiver perform? - Answers- Conversion
of an optical carrier to an electrical signal, and demodulation of the modulated optical
carrier.
What happens if the optical signal exceeds the maximum specified input power into a
photodetector? - Answers- Nonlinear operation resulting in distortion, data errors, and
signal loss.What are the primary causes of intrinsic loss in SMF? - Answers- Material
absorption and Rayleigh scattering
The phenomenon, total internal reflection, is what enables an optical fiber to guide light.
What characteristic of optical fiber causes total internal reflection? - Answers- The
difference in refractive indexes, between cladding, and core,causes light to be reflected
off the cladding and back into the core along the optical fiber.
Where would you expect Fresnel reflections to occur in a fiber-optic network? -
Answers- At connections and mechanical splices where the signal source is entering or
exiting the cable.
Chromatic dispersion is a combination of which two dispersions? - Answers- Material
and waveguide dispersion.
