Chapter 5 Flashcards
Using DWDM, a single fiber can carry between what two numbers of channels? A) 60 B) 80 C) 160 D) 200
B) 80
C) 160
What two items below are commonly expressed as bits transmitted per second? A) frequency B) amplitude C) throughput D) bandwidth
C) throughput
D) bandwidth
What two connector types are typically used to terminate RG-6 and RG-59 cables? A) f-connectors B) BNC C) ST couplers D) J-hooks
A) f-connectors
B) BNC
Frequencies used to convey speech over telephone lines fall between what two frequencies below? A) 100 Hz B) 300 Hz C) 3.3 KHz D) 5.5 KHz
B) 300 Hz
C) 3.3 KHz
What is the maximum supported throughput and bandwidth / signal rate of Cat 5e? A) 100 Mbps B) 1000 Mbps C) 100 MHz D) 350 MHz
B) 1000 Mbps
D) 350 MHz
What term below is used to describe the outer-most layer of protective covering of a coaxial cable? A) sheath B) shield C) braiding D) insulation
A) sheath
What Ethernet standard below is also referred to as "thinnet"? A) 100Base2 B) 10Base2 C) 100BaseT D) 10BaseT
B) 10Base2
What is the minimum category of UTP cable required in order to support Gigabit speeds? A) Cat 3 B) Cat 5 C) Cat 5e D) Cat 6
C) Cat 5e
What is the maximum supported throughput of a CAT6 cable? A) 100 Mbps B) 1 Gbps C) 10 Gbps D) 100 Gbps
C) 10 Gbps
How many cable pairs are needed for 1000Base-T transmission over CAT5e cable? A) 2 B) 4 C) 6 D) 8
B) 4
Standard PoE devices must be provided with how much power in order to function? A) 5 watts B) 12 watts C) 15.4 watts D) 25.5 watts
C) 15.4 watts
What is the maximum distance for 10GBase-ER and 10GBase-EW on a segment of single mode fiber? A) 550m B) 300m C) 10km D) 40km
D) 40km
What type of cross-talk occurs between wire pairs near the source of a signal? A) far end cross talk B) near end cross talk C) alien cross talk D) pair migration cross talk
B) near end cross talk
Which of the following connectors is the most common for mutlimode fiber? A) ST B) SC C) FC D) MT-RJ
D) MT-RJ
A measure of a signal's strength at any given time is known as which term below? A) amplitude B) frequency C) phase D) wavelength
A) amplitude
The number of times that a wave's amplitude cycles from its starting point, through its highest amplitude and its lowest amplitude, and back to its starting point over a fixed period of time, is known as what term below? A) amplitude B) frequency C) wavelength D)phase
B) frequency
WDM divides a beam of light into how many different wavelengths or colors? A) 10 B) 20 C) 30 D) 40
D) 40
Which type of multiplexing is defined by wavelength instead of frequency? A) CWDM B) DWDM C) WDM D) FDM
A) CWDM
Which option below reflects the standard impedance of an RG-6 cable? A) 50 ohms B) 60 ohms C) 65 ohms D) 75 ohms
D) 75 ohms
Phone companies make use of what type of multiplexing in order to allow for phone services and DSL services over the same line? A) WDM B) FDM C) DWDM D) CWDM
B) FDM
The most common multiplexing technology used in conjunction with fiber optics is which option below? A) DWDM B) CWDM C) FDM D) WDM
A) DWDM
A device that is responsible for modulating digital signals into analog signals, and demodulating analog signals into digital signals at the receiving end, is known as? A) a modem B) a transceiver C) a demuxer D) a multiplexer
A) a modem
Ethernet is an example of what type of technology? A) broadband B) baseband C) wideband D) narrowband
B) baseband
Since cable TV and cable internet can share the same coaxial cable, they are considered to be what type of technology? A) broadband B) baseband C) narrowband D) wideband
A) broadband
Using a form of transmission that allows multiple signals to travel simultaneously over one medium is known as which of the following options? A) embedding B) multiplexing C) coupling D) modulating
B) multiplexing
Digital signals are composed of pulses of precise, positive voltages and zero voltages.
(A) True
(B) False
True
A serial cable with an RJ-45 connector is capable of being used through an RJ-45 Ethernet port.
(A) True
(B) False
False
Multimode fiber contains a core that is larger than a single mode fiber core.
(A) True
(B) False
True
Because digital signals do not depend on amplitude or frequency differences to communicate information, they are more vulnerable to EMI noise.
(A) True
(B) False
False
A continuity tester should not be used on a live network segment.
(A) True
(B) False
True
A ______________ is a voltage, frequency, pulse, or phase change in an analog transmission.
Answer : symbol
A _____________ cable reverses all of the wires without regard to how they are paired.
Answer : rollover
____________ causes problems only when a receiving node is expecting some type of communication, such as the rest of the data stream it has begun to accept.
Answer : Latency
A _____________ is a simple instrument that can measure many characteristics of an electric circuit, including its resistance, voltage, and impedance.
Answer : multimeter
A _____________ is a device that retransmits a digital signal in its original form, extending the length of a segment.
Answer : repeater
What term below is used to describe the outer-most layer of protective covering of a coaxial cable? (A) sheath (B) shield C) braiding D) insulation
Sheath
What Ethernet standard below is also referred to as "thinnet"? (A) 100Base2 (B) 10Base2 (C) 100BaseT (D) 10BaseT
Answer : (B)
What is the minimum category of UTP cable required in order to support Gigabit speeds? (A) Cat 3 (B) Cat 5 (C) Cat 5e (D) Cat 6
Answer : (C)
What is the maximum supported throughput of a CAT6 cable? (A) 100 Mbps (B) 1 Gbps (C) 10 Gbps (D) 100 Gbps
Answer : (C)
How many cable pairs are needed for 1000Base-T transmission over CAT5e cable? (A) 2 (B) 4 (C) 6 (D) 8
Answer : (B)
Standard PoE devices must be provided with how much power in order to function? (A) 5 watts (B) 12 watts (C) 15.4 watts (D) 25.5 watts
Answer : (C)
What is the maximum distance for 10GBase-ER and 10GBase-EW on a segment of single mode fiber? (A) 550m (B) 300m (C) 10km (D) 40km
Answer : (D)
What type of cross-talk occurs between wire pairs near the source of a signal? (A) far end cross talk (B) near end cross talk (C) alien cross talk (D) pair migration cross talk
Answer : (B)
Which of the following connectors is the most common for multimode fiber? (A) ST (B) SC (C) FC (D) MT-RJ
Answer : (D)
A measure of a signal's strength at any given time is known as which term below? (A) amplitude (B) frequency (C) phase (D) wavelength
Answer : (A)
The number of times that a wave's amplitude cycles from its starting point, through its highest amplitude and its lowest amplitude, and back to its starting point over a fixed period of time, is known as what term below? (A) amplitude (B) frequency (C) wavelength (D) phase
Answer : (B)
WDM divides a beam of light into how many different wavelengths or colors? (A) 10 (B) 20 C) 30 D) 40)
Answer : (D
Which type of multiplexing is defined by wavelength instead of frequency? (A) CWDM (B) DWDM (C) WDM (D) FDM
Answer : (A)
Which option below reflects the standard impedance of an RG-6 cable? (A) 50 ohms (B) 60 ohms (C) 65 ohms (D) 75 ohms
Answer : (D)
Phone companies make use of what type of multiplexing in order to allow for phone services and DSL services over the same line? (A) WDM (B) FDM (C) DWDM (D) CWDM
Answer : (B)
The most common multiplexing technology used in conjunction with fiber optics is which option below? (A) DWDM (B) CWDM (C) FDM (D) WDM
Answer : (A)
A device that is responsible for modulating digital signals into analog signals, and demodulating analog signals into digital signals at the receiving end, is known as? (A) A modem B) A transceiver (C) A demuxer (D) A multiplexer
Answer : (A)
Ethernet is an example of what type of technology? (A) broadband B) baseband (C) wideband (D) narrowband
Answer : (B)
Since cable TV and cable Internet can share the same coaxial cable, they are considered to be what type of technology? (A) broadband (B) baseband (C) narrowband (D) wideband
Answer : (A)
Using a form of transmission that allows multiple signals to travel simultaneously over one medium is known as which of the following options? (A) embedding (B) multiplexing (C) coupling (D) modulating
Answer : (B)
Describe two ways in which analog and digital signals are boosted
amplifier-Analog signals pass through an amplifier, an electronic device that increases the voltage,
● or strength, of the signals. Unfortunately, the boost can also boost the noise that has accumulated in the signal, which causes the analog signal to worsen progressively. After multiple amplifications, an analog signal may become difficult to decipher. repeater-Recall that a repeater is a device that regenerates a digital signal in its original form,
● without the noise it might have previously accumulated. A switch on an Ethernet network works as a multiport repeater as the bits transmitted “start over” at each port on the switch.
Explain what a TDR is, and describe how it is used.
Explain what a TDR is, and describe how it is used.
Define how phase affects an analog signal
Phase is the progress of a wave over time in relationship to a fixed point. Suppose two separate waves have identical amplitudes and frequencies. If one wave starts at its lowest amplitude at the same time the second wave starts at its highest amplitude, these waves will have different phases. More precisely, they will be 180 degrees out of phase (using the standard assignment of 360 degrees to one complete wave). Had the second wave also started at its lowest amplitude, the two waves would be in phase.
How does a digital signal compare to an analog signal?
Digital signals are composed of pulses of precise, positive voltages and zero voltages. There’s nothing infinite or continuous about a digital signal because it is inherently either on or off. A pulse of positive voltage represents a 1. A pulse of zero voltage (in other words, the lack of any voltage) represents a 0. The use of 1s and 0s to represent information is characteristic of a binary system. Every pulse in the digital signal is a binary digit, or bit. An analog signal, on the other hand, such as the sound of the human voice or music, has an infinite number of tones and subtle inflections. When digitizing sound, the higher the sampling rate, the more accurate the representation of the analog signals. For example, the sampling rate for digitized voice, such as that used by iPhone’ s Siri, is much lower than the sampling rate used for music albums.
What is modulation? Provide two examples of how it can be used.
Data modulation is a technology used to modify analog signals to make them suitable for carrying data over a communication path. In modulation , a simple wave, called a carrier wave, is combined with another analog signal, known as the information or data wave, to produce a unique signal that gets transmitted from one node to another. The carrier wave has preset properties (including frequency, amplitude, and phase). Its purpose is to help convey information; in other words, it’ s only a messenger. When the information wave is added, it modifies one property of the carrier wave (for
example, the frequency, amplitude, or phase). The result is a new, blended signal that contains properties of both the carrier wave and added data. When the signal reaches its destination, the receiver separates the data from the carrier wave. The data is sent on its way to the computer once again as 0s and 1s.
Modulation can be used to make a signal conform to a specific pathway, as in the case of FM (frequency modulation) radio, in which the data must travel along a particular frequency. In frequency modulation, the frequency of the carrier signal is modified by the application of the data signal. In AM (amplitude modulation), the amplitude of the carrier signal is modified by the application of the data signal. Modulation may also be used to issue multiple signals to the same communications channel and prevent the signals from interfering with one another.
When an Ethernet NIC has been configured by the OS to use half-duplex, the transmit pair of
the twisted-pair cable uses _____ transmissions, the receive pair in the cable uses ____
transmissions, and the twisted-pair cable uses ______ transmissions.
A. Simplex, half-duplex, half-duplex
B. Half-duplex, simplex, simplex
C. Simplex, simplex, half-duplex
D. Simplex, half-duplex, simplex
Answer: C. Simplex, simplex, half-duplex
Which of the following is not an example of a broadband transmission? A. Cable TV B. Telephone signal C. Mobile voice D. Ethernet
Answer: D. Ethernet
Which kind of multiplexing assigns slots to nodes according to priority and need?
A. WDM (wavelength division multiplexing)
B. Statistical multiplexing
C. TDM (time division multiplexing)
D. CWDM (coarse wavelength division multiplexing)
Answer: B. Statistical multiplexing
Which type of transmission is measured by baud rate? A. Analog B. Digital C. Baseband D. Broadband
Answer: A. Analog
What kind of cable uses BNC connectors? F-connectors? Which connector is likely to be
used by cable TV?
A. Coaxial cable, coaxial cable, F-connector
B. Coaxial cable, UTP, BNC connector
C. STP, UTP, F-connector
D. SMF, MMF, BNC connector
Answer: A. Coaxial cable, coaxial cable, F-connector
Which categories of twisted-pair cable can support Gigabit Ethernet? A. Cat 5 and lower B. Cat 5 and higher C. Cat 5e and higher D. Cat 6 and lower
Answer: C. Cat 5e and higher
What is the earliest twisted-pair cabling standard that meets the minimum requirements for 10GBase-T transmissions? A. Cat 5 B. Cat 5e C. Cat 6 D. Cat 6a
Answer: C. Cat 6
Which type of cross-talk occurs between wire pairs near the source of a signal? A. Alien cross-talk B. Tx/Rx reverse C. FEXT D. NEXT
Answer: D. NEXT
What device can boost an analog signal? A digital signal? A. Toner probe, multimeter B. Repeater, certifier C. Amplifier, repeater D. TDR, multimeter
Answer: C. Amplifier, repeater
Which part of a toner and probe kit emits a tone when it detects electrical activity on a wire pair? A. Probe B. Tone generator C. Toner probe D. Toner
Answer: A. Probe
What are the four fundamental properties of an analog signal?
Answer: Amplitude, frequency, wavelength, and phase
What does a modem do?
13
Answer: A modem modulates digital signals into analog signals at the transmitting end, then
demodulates analog signals into digital signals at the receiving end.
What is twist ratio and why is it important?
Answer: Twist ratio is the number of twists per meter or foot. The more twists per foot in a pair
of wires, the more resistant the pair will be to cross-talk or noise.
What fiber is used in fiber-optic cabling to protect the inner core and prevent the cable from
stretching?
Answer: Kevlar, a polymeric fiber
What characteristic of optical transmissions is primarily responsible for the distance
limitations of fiber-optic cabling?
Answer: Optical loss, which is the degradation of the light signal after it travels a certain distance
away from its source
Why is SMF more efficient over long distances than MMF?
Answer: The core of SMF is much narrower than that of MMF, and reflects very little. The light
does not disperse as much along the fiber.
Why do APC ferrules create less back reflection than do UPC ferrules?
Answer: The end faces are placed at an angle to each other, so the reflection is sent back in a
different direction than the source of the signal
What does a fiber cleaver do?
Answer: It scores the fiber strand for breaking, but does not cut it.
Answer: It scores the fiber strand for breaking, but does not cut it.
How is latency measured and in what unit?
Answer: By calculating a packet’s RTT, or the length of time it takes for a packet to go from
sender to receiver, then back from receiver to sender. RTT is usually measured in milliseconds.
What is the difference between short circuits and open circuits?
Answer: A short circuit is one where connections exist in places they shouldn’t, whereas an open
circuit is one where needed connections are missing.
Which term represents an analog wave’s strength?
a. Phase
b. Wavelength
c. Frequency
d. Amplitude
Answer: D
Which type of modulation occurs when the amplitude of the carrier signal is modified by the application of the data signal?
a. Statistical modulation
b. Frequency modulation
c. Amplitude modulation
d. Data modulation
Answer: C
In ____ multiplexing, the transmitter assigns slots to nodes according to priority and need.
a. statistical
b. frequency division
c. wavelength division
d. dense wavelength division
Answer: A
True or False: A high twist ratio can result in lower attenuation.
Answer: False
Which cabling consists of one or more insulated wire pairs encased in a plastic sheath?
a. STP (Shielded twisted pair)
b. UTP (Unshielded twisted pair)
c. Coaxial
d. Fiber-optic
Answer: B
True or False: Fiber-optic cable is the most expensive transmission medium.
Answer: True
Which of the following connectors uses a polished curved surface but has end faces that are placed at an angle to each other?
a. PC
b. UPC
c. APC
d. ST
Answer: C
A hardware component that can be changed without disrupting operations is known as _____.
Answer: hot-swappable
True or False: EMI (electromagnetic interference) is a latency issue.
Answer: False
The difference between continuity testers and performance testers lies in their sophistication and price.
Answer: True
What type of connector does a 100Base-T network require?
a. RJ-11
b. BNC
c. AUI
d. RJ-45
d. RJ-45
What is the signal rate for Cat 5e cable?
a. 16 MHz
b. 100 MHz
c. 350 MHz
d. 500 MHz
c. 350 MHz
Which of the following is commonly used to protect UTP cable from EMI?
a. Conduit
b. STP
c. Crossover cable
d. Lead shielding
a. Conduit
What is the maximum throughput of a 100Base-TX network?
a. 5 Mbps
b. 10 Mbps
c. 50 Mbps
d. 100 Mbps
d. 100 Mbps
The 1000Base-TX standard requires _____ cabling or better.
a. Cat 3
b. Cat 5
c. Cat 5e
d. Cat 6
d. Cat 6
How much power does standard PoE provide?
a. 15.4 watts
b. 25.5 watts
c. 45 watts
d. Unlimited
a. 15.4 watts
What is one use for a crossover cable?
a. To connect a hub and a workstation
b. To connect a workstation to a wall jack
c. To connect two workstations directly
d. To connect a workstation to a modem
c. To connect two workstations directly
Which of the following tools would be useful in creating a patch cable for a 100Base-T network?
a. Screwdriver
b. Crimper
c. Soldering iron
d. Pliers
b. Crimper
What type of cable would connect a workstation to the wall jack in the work area of a 100Base-T network?
a. Straight-through cable
b. Crossover cable
c. Coaxial cable
d. Punch-down cable
a. Straight-through cable
In twisted-pair wire, how does the twist ratio affect transmission? (Choose all that apply.)
a. The more twists per inch, the less cross-talk transmission will suffer.
b. The more twists per inch, the slower the transmission.
c. The more twists per inch, the more attenuation transmission will suffer.
d. The more twists per inch, the faster the transmission.
c. The more twists per inch, the more attenuation transmission will suffer.
What is the maximum speed at which Category 3 UTP can transmit data?
a. 1 Mbps
b. 10 Mbps
c. 100 Mbps
d. 1 Gbps
b. 10 Mbps
What type of cable is required for 100Base-FX?
a. Coaxial cable
b. UTP
c. STP
d. Fiber-optic cable
d. Fiber-optic cable
Increasing the twist ratio makes twisted-pair cabling more resistant to ______.
a. Stretching
b. Fire
c. Cross-talk
d. Attenuation
c. Cross-talk
What might cause a 100Base-TX network to experience an average throughput of less than 100 Mbps? (Choose all that apply.)
a. Heavy traffic on the network
b. Miswired cables
c. Too many protocols bound on the server
d. A mix of different network operating systems on the servers
a. Heavy traffic on the network
b. Miswired cables
What does the “T” in 10Base-T and 100Base-T stand for?
a. Transmission
b. Transport layer
c. Twisted-pair
d. Transparent
c. Twisted-pair
What type of cable is required for a 100Base-T network?
a. Cat 3 or higher
b. Cat 5 or higher
c. Cat 6 or higher
d. Cat 7 or higher
b. Cat 5 or higher
Where would you find a plenum cable?
a. Above the ceiling tiles in an office
b. In an outdoor cable trench that leads to a building
c. Between a hub and a punch-down panel
d. Between a workstation and a wall jack
a. Above the ceiling tiles in an office
What organization is responsible for establishing structured wiring standards?
a. TIA/EIA
b. ANSI
c. ITU
d. FCC
a. TIA/EIA
What pin number is used for transmitting a positive signal on an RJ-45 straight-through patch cable?
a. 1
b. 2
c. 5
d. 6
a. 1
Which of the following could be a symptom of a damaged patch cable between a workstation and the wall jack on a UTP network? (Choose all that apply.)
a. The workstation cannot send or receive data to or from the network.
b. The workstation and other workstations in the same office cannot send or receive data to or from the network.
c. The workstation can send data to the network, but cannot receive data from the network.
d. All workstations on the same segment can send data to the network, but cannot receive data from the network.
a. The workstation cannot send or receive data to or from the network.
How many wire pairs are in a typical Category 5 cable?
a. 2
b. 3
c. 4
d. 6
c. 4
How does bend radius affect transmission?
a. Transmission will not be successful until the bend radius has been reached.
b. Transmission cannot occur at the bend radius.
c. Transmission will be unreliable after the bend radius is exceeded.
d. Transmission will be less secure after the bend radius is exceeded.
Transmission will be unreliable after the bend radius is exceeded.
What problem could be caused by laying cable in the ceiling tiles six inches above a bank of fluorescent lights?
a. Increased latency
b. EMI
c. Fire hazard
d. Decreased bend radius
b. EMI
Which of the following is not an advantage of fiber cables over UTP cables?
a. Fiber is not susceptible to electric interference, whereas UTP cable is.
b. Fiber is less fragile than UTP cable.
c. Fiber is more expensive than UTP cable.
d. Fiber can transmit data over longer distances than UTP cable.
c. Fiber is more expensive than UTP cable.
You work for a small ISP. Which fiber technology would be best for connecting to your telecommunications carrier over a distance of 2.8 miles?
a. 1000Base-LX
b. 1000Base-SX
c. 10 GBase-SR
d. 1000Base-T
a. 1000Base-LX
In which of the following situations would it be possible to use a UTP cable standard such as 1000Base-CX over a fiber-optic cable standard such as 1000Base-LX or 1000Base-T?
a. When connecting two data centers over distances of 2 km or less
b. When connecting short distances of 25 meters or less between network devices and servers inside a single data center
c. When connecting short distances of 200 meters or less between network devices and workstations inside a building
d. When connecting buildings inside a campus over distances of 500 meters or less
b. When connecting short distances of 25 meters or less between network devices and servers inside a single data center
Which of the following problems could cause signal loss in fiber-optic cable?
a. Cross-talk between strands of fiber in multimode fiber cables
b. Cross-talk between cables in single-mode fiber cables
c. Electromagnetic interference caused by power lines near the cables
d. Dirty connectors
d. Dirty connectors
100Base-FX requires multimode fiber cable with two or more strands. How are these strands used to transmit and receive data? (Choose all that apply.)
a. One strand is used for both transmission and reception in both full- and half-duplex.
b. Both strands are used for transmission and reception in full-duplex.
c. One strand is used for transmission and the other is used for reception in half-duplex.
d. Both strands are used for transmission and reception in full-duplex, whereas there is no half-duplex for 100Base-FX.
a. One strand is used for both transmission and reception in both full- and half-duplex.
b. Both strands are used for transmission and reception in full-duplex.
A higher twist ratio causes less _______ but more attenuation.
a. Shielding
b. Cost
c. Noise
d. Cross-talk
d. Cross-talk
How many pairs of wires are used for transmission in Gigabit Ethernet?
a. 4
b. 3
c. 2
d. 1
a. 4
What is the maximum throughput of a 100Base-TX network?
a. 5 Mbps
b. 10 Mbps
c. 50 Mbps
d. 100 Mbps
d. 100 Mbps
A TIA/EIA 568A pinout on one side and a 568B pinout on the other will make a _____ cable.
a. Straight-through
b. Patch
c. Crossover
d. Rollover
c. Crossover
This kind of cable can be used to connect a computer to the console port of a router.
a. Straight-through
b. Patch
c. Crossover
d. Rollover
d. Rollover
