1. ELET 4315 Homework #4 (Chapters 13 – 17)
Chapter 13
What are the two primary transmission parameters engineers use when designing a circuit?
Engineers design communication circuits around two general transmission parameters: signal
loss and bandwidth.
Circuit bandwidth is dependent on amount of signal loss of the physical medium.
List the five common factors used when designing a circuit.
(1) The distance between transmitter and receiver
(2) The strength or power of the transmitted signal
(3) Receiver sensitivity
(4) The type of frequencies being transmitted
(5) Interferences of disturbers on the line such as noise from power stations or crossover from an
adjoining circuit.
A 26 gauge wire has a lower resistive value than a 24 gauge wire.
a. True b. False
Explain how the telephone line acts like a capacitor.
A telephone circuit composed of two wire strands separated by air like a capacitor, since a
capacitor is composed of two conductors placed in parallel with an insulating material or
dielectric material in between. In a telephone circuit the two wires make up the conductors and
the air separating the two wires is the dielectric insulator.
Engineers place load coils in the circuit to:
a. Amplify the voice signal in order to extend its reach down the line.
b. Reduce the amount of loss in the circuit.
c. Filter out cross talk coming from adjacent circuits.
d. Counteract the capacitive effect on the circuit allowing the signal to travel
farther down the line.
e. None of the above.
f. All of the above.

2. Load coils are placed on all circuits greater than 18,000 feet including DSL and ISDN circuits.
a. True b. False
Explain why light travels farther down a single mode fiber strand than a multimode fiber strand.
Light contained in a very small diameter core can travel many miles before needing to be
boosted or regenerated. The rule of thumb is the smaller the core the farther the signal can travel.
The size of the core is what differentiates multimode and single mode fiber. Multimode fiber has
a much larger core diameter when compared to single mode. Multimode ranges from 50um to
62um while single mode core diameter ranges between 7um and 10um. As the name imply
while single mod fiber has one mode or path to travel while multimode fiber has multiple
modes or paths for light to travel.
Inherent properties found in fiber that contribute to signal loss - light losing power are:
a. EMF
b. Absorption
c. Scattering
d. Radiation
e. All of the above
f. b, c, and d only
g. a, and d only
Properties produced by man-made events that contribute to signal loss in fiber are:
a. Dirt on the end of the fiber
b. Violating the Bend radius
c. EMF
d. Misaligned splice
e. a, c, d
f. a, b, d
g. All of the above
Explain the term dispersion as it relates to fiber optic transmission systems.
Dispersion is similar to attenuation affects how far the signal can travel before needing to be
amplified or regenerated. Dispersion causes the light pulse to spread or disperse, making it
difficult for the end equipment to determine if it is seeing a one or a zero.

3. The 1310nm wavelength has a dispersion point and on average experiences ___db/km of
loss.
a. 10 and .15
b. -.5 and .15
c. 0 and .25
d. 0 and .35
e. None of the above
Loss across a fiber span is measured in and the power level from the optical
transmitter is measured using .
a. dBm and dB
b. dB and dBm
c. dB and dB
d. dBM and dBm
e. mW and dBm
f. dB and mW
g. None of the above
The C- band, _Ku-band,and Ka-bandare usedfor satellitesystems.
What does VSAT stand for and where might they be deployed.
Very small aperture terminal satellite link is a good example of a direct signal. is a two-way
satellite ground station or a stabilized maritime VSAT antenna with a dish antenna that is smaller
than 3 meters. The majority of VSAT antennas range from 75 cm to 1.2 m. Data rates typically
range from 4 Kbit/s up to 4 Mbit/s and sometimes up to a max downlink of up to 16 Mbit/s with
some upgraded modules and enhancements. VSATs access satellite(s) in geosynchronous orbit to
relay data from small remote earth stations (terminals) to other terminals (in mesh topology) or
master earth station "hubs" (in star topology).
VSATs are most commonly used to transmit narrowband data (point of sale transactions such as
credit card, polling or RFID data; or SCADA), or broadband data (for the provision of satellite
Internet access to remote locations, VoIP or video). VSATs are also used for transportable, on-
the-move (utilizing phased array antennas) or mobile maritime communications.
VSAT systems generally connect a large number of geographically dispersed sites to a central
location. VSAT networks may transmit voice, data, fax, or video conferencing. The VSAT
market has been going since the early 1980s and the launch of the first one-way VSAT system
by Equatorial of California. Towards 1985 the first interactive star systems began to be seen and
it wasn’t until 1989 that the first mesh telephony products were really sold.You name it really,

4. car dealerships, gas stations, banks, insurance companies, drug stores, general stores,
supermarkets, healthcare companies, manufacturers, couriers, hotel chains, car rental businesses,
food manufacturers, heavy industries, mines, electrical utilities, oil and gas pipelines, energy
production and exploration, timber companies, plantations, various government departments and
agencies
Chapter 14
Placing communications cable in a trench is referred to as gel-filled cable _____cable.
Trenches used to hold the cable are most commonly found in:
a. Metropolitan networks
b. Rural areas
c. New Developments
d. Access Networks
e. B, c, and d
f. All of the above
Demarcation point is the term used to describe the junction between the feeder cable and the
distribution cable.
a. True b. False
Which statement or statements are true.
a. A 26 gauge wire is smaller in diameter than a 24 gauge wire.
b. A 26 gauge wire has a lower resistance value per foot than a 24 gauge wire.
c. A 24 gauge wire is smaller in diameter than a 26 gauge wire.
d. A 24 gauge wire has a lower resistance value per foot than a 26 gauge wire.
e. A 19 gauge wire has a smaller diameter than a 26 gauge wire.
f. A 19 gauge wire has a lower resistance value than a 24 and 26 gauge wire.
g. b, and e
h. a, f, d
i. a, d, f
j. None of the above
A load coil is used to extend the distance a voice analog signal can travel down a copper pair.
a. True b. False
The most common color code used to define copper outside plant cable is:

5. a. Orange, Blue, White, Brown, Slate
b. Green, Orange, Blue, White, Brown, Slate
c. White, Red, Black, Yellow, Violet
d. Blue, Orange, Green, Brown, Slate
The CSA refers to the area surrounding an alternate carriers long distance POP, Point of
Presence.
a. True b. False
T1 Carrier housings are located on average 6000___feet apart and 12000 feet from the central
office and end location.
The standard fiber color code is:
a. Green, orange, blue, white, brown, violet and rose.
b. Blue, orange, green, brown, slate, white, red, black, yellow, violet, rose,
aqua.
c. Blue, orange, green, brown, slate
d. Blue, white, orange, black, red, yellow, violet, rose, aqua, brown
e. None of the above.
Explain the difference between fiber miles and route miles as it pertains to fiber optic systems.
Route miles is the physical distance of the fiber span from point A to point B. Route miles do not
take slack loop lengths into consideration. Route miles are always shorter than fiber miles.
Whereas Fiber miles are the Length of fiber deployed in the span from point A to point B. This
includes all slack loops. Fiber miles are always longer than route.
Explain why a separate copper wire is buried with the fiber optic cable.
It is used to trace the wire, that is a marker signifying where the cable is buried
Plenum refers to a cable that can be used on the inside plant and outside plant.
a. True b. False
Chapter 15
The primary reason DWDM systems are used in long haul networks is to increases the number of
circuits that can be carried on a single fiber strand.
a. True b. False

6. The core network architecture is:
a. Point to point, mesh
b. Point to point, mesh, ring, linear
c. Point to point, ring
d. Mesh
e. None of the above
A SONET mux converts a DS1 framed signal into a __48_, and a DS3 framed signal into a_1.
A Digital Cross Connect system is used to groom channels within one circuit to another circuit
through an electronic cross connect.
a. True b. False
Define the term lambda.
A term used to define the wavelength.
What does EDFA stand for and what how is it used in an optical network.
Erbium –doped fiber amplifier, used in long haul networks to boost the strength. They function
best within the frequency range between 1530nm-1565nm and are the main reason for the C-
band ‘s popularity in the long-haul network. It extends the reach of the signal
Define the term POP.
Point of presence the term is used to represent the interconnection location whether that is a
full blown switch site or the hub. A point of presence (PoP) is an artificial demarcation point or
interface point between communicating entities. It may include a meet-me-room. In the US, this
term became important during the court-ordered breakup of the Bell Telephone system. A point
of presence was a location where a long-distance carrier (IXC) could terminate services and
provide connections into a local telephone network (LATA). An Internet point of presence is an
access point to the Internet. It is a physical location that houses servers, routers, ATM switches
and digital/analog call aggregators. It may be either part of the facilities of a telecommunications
provider that the Internet service provider (ISP) rents or a location separate from the
telecommunications provider. ISPs typically have multiple PoPs, sometimes numbering in the
thousands. PoPs are also located at Internet exchange points and colocation centers.

7. Chapter 16
A metropolitan network carries information between locations within the metropolitan area such
as between central offices, ISPs, POP and ISP, large businesses.
a. True b. False
List four of the most common network topologies deployed in the metropolitan space.
Ring, mesh , linear, and point to point
The common protocols deployed in the metropolitan network are:
a. ATM, IP, MPLS, Frame Relay,
b. ATM, IP, MPLS, Frame Relay, Ethernet
c. IP, MPLS, Ethernet
d. SONET, TDM Asynchronous,
e. A and d
f. B and d
g. All of the above
A channel bank aggregates subscriber circuits such as FX, DDS, ISDN into SONET OC-N
circuits.
a. True b. False
The M13 multimplexer is used to:
a. Multiplex 24 DS1 circuits into one M13 framed DS3 signal.
b. Multiplex 672 DS0s into one M13 framed DS3 signal.
c. Multiplex 28 DS1 signals into one M13 framed DS3 signal.
d.
e. Multiplex 24 64kbps circuits into one M13 framed DS3 signal.
f. Multiplex 24 64kbps circuits into 1 DS1 signal.
g. A, and b
h. B, and c
i. b, c, e
j. All of the above

8. Ethernet has become one of the most popular transport methods used in the metro space due to
the following:
a. Ethernet provides an easy method for handling layer 3 functionality.
b. Ethernet is already used in the LAN space making it less “scary” to IT
managers needing to deploy a WAN solution.
c. Ethernet equipment is inexpensive.
d. Newer Ethernet interfaces, Fast E and GigE provide a high bandwidth
WAN pipe.
e. Service providers started offering low cost, high bandwidth Ethernet
pipes.
f. A, b and d
g. B, c and d, e
h. All of the above
A narrow band DCS aggregates lower speed channels into higher speed channels by grooming
into ___.
a. DS1s into DS3s
b. DS3s into STS-1s
c. DS1s into VT-1s
d. DS0s into VT-1s
e. DS0s into DS1s
f. None of the above
A broadband DCS is used to groom lower speed circuits into higher speed circuits. It grooms
into ___.
a. DS1 into DS3
b. DS3 into STS-1
c. DS1 into VT-1
d. DS3 into OC-3
e. STS-1 into OC-3 or 12
f. OC-3 or 12 into OC-48
g. STS-1s into OC-48
h. All of the above
What does PON stand for and why is it used in the metropolitan network.
Passive optical network A fiber optic network with passive filters deployed to carry multiple
wavelengths across the fiber optic band , they are used to increase the capacity of the fiber optic
strands.

9. Explain the difference between a CWDM system and a DWDM system.
CWDM is coarse wave division multiplexing it is a WDM technology that multiplexes
wavelengths together on one fiber optic strand. CWDM differs for WDM primarily in the
number of channels of wavelength it can multiplex. DWDM is dense wave division
multiplexing, equipment that multiplexes wavelengths across optical networks.
Chapter 17
List four types of carriers that offer services over the access network.
Plain old telephone service, ISDN service, Special services Circuits, Broadband services,T-
Carrier, Gigabit and Fast Ethernet Services
Define the access network as it pertains to the communications network.
The Access network is a term used to describe the types of circuits used to service the end user in
the metropolitan area.
The following are considered part of the access network.
a. Central office
b. ISDN circuit
c. POTS line
d. FX circuit
e. Broadband pipe
f. T-1
g. GigE
h. All of the above
What is the term used to describe traditional analog telephone service.
POTS plain old telephone service
The conductors that make up the copper pair are referred to as tip ____and___ring_____.
The term drop line is used to refer to the cable that is dropped off the back of the DSL modem
and used to connect to the terminating equipment.
a. True b. False
The outside plant cables are terminated on the __MDF(Main distribution frame) in the central
office.

10. The 56kbps digital circuit was the first digital circuit offered to the subscriber by the telephone
company.
a. True b. False.
The term Loop start and E&M refer to ____signaling______________________methods.
What advantage does a broadband pipe provide the end user?
Broadband pipe provide the end user with megabits per seconds of information into the home
there they get more information.