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. 5.
This exercise covers the design of a Campus LAN Backbone. A college is upgrading their
networks with extensive high tech equipment. They use a fiber optic backbone for their LAN, VoIP,
WiFi and other building automation and security systems already but are upgrading to Gigabit Ethernet
today and plan to go to higher speeds in the future. The links run from computer room to switches,
but exit both buildings for a link across campus run in conduit in access tunnels under campus.
Basic System Information: This is the
basic layout of a cable run, with the middle span ( the span with the dots on the cable between the
two center connections) run in conduit between buildings and the rest of the cable indoors) There is
a permanently installed 144 fiber backbone cable with intermediate patching in buildings for runs to
equipment rooms patchcords to the equipment on either end. The total fiber/cable length varies to
each building, with runs of 175, 240, 290 and 300m meters including the permanently installed cable
and patchcords of 2 m on each end.
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 Ethernet at 10 Gb/s speeds.
Multimode fiber will be used.
What will be the wavelength used for
transmission?
a. | 1310 nm | b. | 850
nm | c. | 1550 nm | d. | 650
nm |
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3.
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Which one of the following multimode fibers are appropriate
for this network?
OM1 OM2 OM3 OM4
a. | Any of these fibers will work | b. | Either OM3 or OM4 | c. | Either OM1 or
OM2 | d. | OM4 only |
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4.
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If the network is planned for upgrades to 40 or 100
Gb/s over multimode fibers, the same fibers can be used but what must be included in the design
plans?
a. | Better connectors | b. | Additional fibers for parallel transmission | c. | Fibers with less delay variation | d. | Lower loss in the
link |
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5.
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If the network is planned for upgrades to 40 Gb/s using the
same multimode fibers, how many fibers must be included in the design plans?
a. | 2 fibers per link | b. | 4 fibers per link | c. | 8 fibers per
link | d. | 12 fibers per link |
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6.
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If the network is planned for upgrades to 100 Gb/s using the
same multimode fibers, how many fibers must be included in the design plans?
a. | 2 fibers per link | b. | 4 fibers per link | c. | 12 fibers per
link | d. | 24 fibers per link |
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7.
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If the network is planned for upgrades to 40 or 100
Gb/s but will use singlemode transmission, how many fibers must be included in the design plans?
a. | 2 fibers per link | b. | 4 fibers per link | c. | 12 fibers per
link | d. | 24 fibers per link |
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8.
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The cable chosen for inside the buildings is a distribution
design to be laid in cable trays inside the office building so it must also be _____.
a. | Rated for pulling tension | b. | Rated for flame retardance | c. | Armored | d. | Water-blocked |
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9.
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The cable for the outside plant runs inside conduit can
be _____.
a. | OSP loose tube cable | b. | Indoor/Outdoor distribution cable | c. | Either A or
B | d. | Neither A nor B |
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10.
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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 | | Multimode
at 850 nm | 3.0 dB/km (TIA 568: 3.5 dB/km) | Multimode at 1300 nm | 1.0 dB/km (TIA 568: 1.5 dB/km) | | | Splice Loss | (TIA 568: 0.3 dB, all
types) | | | Connector Loss | (TIA 568: 0.75 dB, all types) | Multimode, adhesive/polish | 0.3
dB | Multimode,
prepolish/splice | 0.5 dB | | |
Active Device and System Specifications | | | Digital Transceiver Specs1 | Power (dBm), T=transmit, R=receive | 850 VCSEL (>1 Gb/s) | T: -3
to -9 dBm, R: 0 > -18 dBm | | |
Transmitter and receiver
specs do not reflect bandwidth penalties incurred by the length of the optical fiber and its
bandwidth performance. 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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11.
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Using the information supplied above, assuming the component
specifications are per TIA standards, calculate the cable plant loss budget for the 300m link,
including the loss of the patchcords.
a. | 2.70dB | b. | 5.55
dB | c. | 4.05 dB | d. | 2.11
dB |
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12.
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Using the information supplied above, assuming the component
specifications are typical values and connectors are adhesive/polish types, calculate the cable plant
loss budget for this link.
a. | 2.70 dB | b. | 5.55
dB | c. | 4.05 dB | d. | 2.11
dB |
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13.
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Using the link specifications for networks from the FOA
Online Reference Guide (http://www.thefoa.org/tech/Linkspec.htm) and the HIGHEST loss permitted by
the TIA component specifications, which is the highest speed link that will work over the
fiber?
a. | 1000BASE-SX | b. | 10GBASE-S | c. | 4G Fibre
Channel | d. | None of these |
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14.
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Using the link loss budgets calculated above and
specifications for networks from the FOA Online Reference Guide
(http://www.thefoa.org/tech/Linkspec.htm), what are the options for making this link work with 10G
Ethernet or Fibre Channel?
a. | Reduce link length but leave high loss
connectors | b. | Reduce connector loss
limits or replace some with low loss splices | c. | Choose lower loss
fiber | d. | Try it anyway, there's always some "fudge factor"
in standards |
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Multiple Response Identify one
or more choices that best complete the statement or answer the question.
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15.
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What parameters should be tested and documented to confirm
proper installation?
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16.
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Testing of each fiber in the cable should be done as
follows: (Choose all the correct answers)
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