Completion Complete each
statement.
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1.
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This is The FOA Online Design Self-Study Program Case Study
No. 2.
This exercise covers the design of a Metropolitan Telecom Network
A medium sized
town is connecting two COs with fiber optics, upgrading from old copper cables.
Basic System Information: The total
fiber/cable distance is 16 km. The cable is pulled underground in existing ducts and fusion spliced
at 9 different points, plus 2 pigtails are spliced on the ends for termination. The system will
be transmitting at OC-48 speeds (2.5 Gb/s) and at some point will be using DWDM for maximum fiber
utilization.
Please enter your name, CFOT/Membership number and date to begin this
exercise.
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Multiple Choice Identify the
choice that best completes the statement or answers the question.
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2.
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The system will be transmitting at OC-48 speeds (2.5 Gb/s)
and will be using DWDM for maximum fiber utilization.
What will be the wavelength used for
transmission?
a. | 1310 nm | b. | 1490
nm | c. | 1550 nm | d. | 1310 and 1550
nm |
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3.
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Which one of the following fibers are appropriate for this
network?
ITU G.652 ITU
G.653 ITU G.654 ITU
G.655
a. | Any of these fibers will work since the link is
short | b. | Only non-zero dispersion shifted fiber | c. | Only low water peak fiber | d. | Only cutoff shifted
fiber |
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4.
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If the network is planned for upgrades to 10, 40 or even 100
Gb/s, which fibers are the best choice for this network?
a. | Any fiber will work since the link is
short | b. | Only non-zero dispersion shifted fiber | c. | Only low water peak fiber | d. | Only cutoff shifted
fiber |
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5.
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The cable chosen is a loose-tube design because the cable
must be _____.
a. | Water-blocked and armored | b. | Water-blocked and rated for high pulling tension | c. | Rated for aerial installation without a messenger | d. | UL Listed for flame retardance |
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6.
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How many fibers should be in the cable?
a. | As few as possible to reduce cable size and
weight | b. | As few as possible to reduce cable and splicing
cost | c. | As many as possible to allow maximum flexibility and
upgrades | d. | Only as many as needed |
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7.
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In order to ensure the system will work on the cable plant
being designed, it is necessary to have what information on the communication system intended for use
on the cable plant?
a. | Wavelength | b. | Transmitter min/max power
output | c. | Receiver min/max input powers | d. | All of the above |
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Typical Specifications Provided for use as case
studies for design labs in FOA courses.
Component
Specifications | | | Fiber
Loss | | Singlemode
at 1310 nm | 0.4 dB/km (TIA 568: 1 dB/km) | Singlemode at 1550 nm | 0.25 dB/km | | | Splice
Loss | (TIA 568: 0.3 dB, all types) | Singlemode, fusion | 0.05 dB | Singlemode, mechanical | 0.3 dB | | | Connector Loss | (TIA 568: 0.75 dB, all
types) | Singlemode,
adhesive/polish | 0.3 dB | | |
Active Device and System Specifications | | | Digital Transceiver Specs1 | Power (dBm), T=transmit, R=receive | 1310 laser (>1 Gb/s) | T: +3 to -3
dBm, R: -10 > -20 | 1550 laser (>1 Gb/s) | T: +3 to -3 dBm, R: -10
> -20 | Fiber
Amplifier | Gain +17 dB | DWDM Module Loss #channels/dB | 8 ch/4 dB,
16 ch/5dB, 32 ch/6 dB | | |
Link margin specifications for most
standardized fiber optic networks are on the FOA Tech Topics Site
(http://www.thefoa.org/tech/Linkspec.htm). It should be used as a reference for designers and for the
courses.
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8.
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Using the information supplied, calculate the cable plant
loss budget for this link. Use the infomation in the "Typical Specifications" narrative
above.
a. | 7.55 dB | b. | 5.15
dB | c. | 6.05 dB | d. | 20.8
dB |
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9.
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With just a single wavelength, the transmitter output
power may be between +3 and -3 dBm and the receiver needs power level to be between -10 and -20 dBm,
will the system operate on this cable plant?
a. | Yes | b. | Yes, but only with a 5 dB
attenuator at the transmitter end | c. | Yes, but only with a 5 dB
attenuator at the receiver end | d. | No, it cannot work under
any circumstances |
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10.
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If DWDM is used, with the transmitter output power and
the receiver power level listed, the 32 channel DWDM module, will the system operate on this cable
plant?
a. | Yes | b. | Yes, but only with an
attenuator at the transmitter end | c. | Yes, but only with an
attenuator at the receiver end | d. | No, it cannot work under
any circumstances |
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Multiple Response Identify one
or more choices that best complete the statement or answer the question.
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11.
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What parameters should be tested and documented to confirm
proper installation?
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12.
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Testing of each fiber should be done as follows: (Choose
all the correct answers)
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13.
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If the links were to be installed aerially, what are the
options for cable installation?
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14.
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What should be included in the design documents to have the
customer prepare for restoration in case of an outage?
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