NCTI Field Tech 2 to 3 Exam Study Guide Questions With
100% Solutions
What does a set-top box (STB) diagnostic page of a quadrature amplitude
modulation(QAM) channel showing signal-to-noise ratio(SNR) near or below 30 dB
indicate - ANSWER the QAM channel quality is on the edge for reliable reception, and
the source of the problem is likely in the distribution network or customer premises
Which Data Over Cable Service Interface Specification (DOCSIS) layer is used by cable
modem termination system (CMTS) to differentiate between cable modems - ANSWER
the DOCSIS Media Access Control (MAC) Layer
What was introduced in Data Over Cable Service Interface Specification(DOCSIS) 3.0
to allow enough bandwidth for upstream carriers from previous DOCSIS versions -
ANSWER The option to increase the top frequency of the upstream to 85MHz
In a Data Over Cable Service Interface Specification (DOCSIS) network, why is the
data throughput over the return or upstream path typically less than the throughput of
data over the forward or downstream path - ANSWER Compared to the downstream
path, the narrower bandwidths and lower orders of modulation used to transport data
over the return path cause the downstream and upstream data throughput to be
unequal or asymmetrical
What would be the downstream throughput if two quadrature amplitude modulation
(QAM) channels with a throughput of 38 Mbps were bonded - ANSWER 76 Mbps
What are two features that were added in Data Over Cable Service Interface
Specification(DOCSIS) 3.1 to extend the viability of hybrid fiber/coax(HFC) network into
the next decade - ANSWER Orthogonal frequency division multiplexing(OFDM) and
low-density parity-check (LDPC)
How does Internet Protocol (IP) multicast differ from IP broadcast - ANSWER IP
multicast traffic is only sent to specific modem addresses on the network; IP broadcast
traffic is sent to all modems on the network
Which step in the troubleshooting process requires a discussion with the customer to
gather more detail about the problem - ANSWER Step 1: Identify the Problem
When analyzing a problem, what can the technician learn by asking the customer to
show or demonstrate the problem - ANSWER The symptoms of the problem can be
,viewed and any unusual screens or customer entries can be identified
When using a digital signal analyzer to troubleshoot data throughput in the Data Over
Cable Service Interface Specification (DOCSIS) network, what is the minimum
modulation error ratio(MER) into the cable modem for a 256-quadrature amplitude
modulation(QAM) carrier - ANSWER 32 dB or greater
What layers of the Open Systems Interconnection (OSI) reference model are specific to
cable networks and are present only between Data Over Cable Service Interface
Specification (DOCSIS) modems and the cable modem termination system (CMTS)? -
ANSWER Layers 1 through 4 (Physical layer, Data Link Layer, Network Layer, and
Transport Layer) are applied between the DOCSIS modem and CMTS
A customer reports a problem of no dial tone(NDT) Upon Inspection, the tech notices
that new carpenting has been installed. What should the tech do next - ANSWER Look
for a cable that runs under the carpet; it is likely that the cable has a short from the
carpeting tack strip
What is the likely problem when there is dial tone on one phone connected to an outlet,
but not on two other phones connected to two different outlets - ANSWER An open
circuit caused by a break in a conductor, poor contact in a modular connector, or an
incorrect wire connection
In the customer premises, what could cause some dual tone multifrequency (DTMF)
touch-tone telephones to have continuous dial tone caused by polarity reversal, but not
other DTMF telephones - ANSWER The telephone wiring polarity is incorrect, and the
customer has a mix of older and newer DTMF touch-tone telephones
What should be checked as a possible cause of hum on a customer's telephone line -
ANSWER Shielding problems in the station wiring, poor terminations, or poor
grounding and bonding connections
What is the difference between the wiring configurations for a residential 8-position,
8contact(8P8C) modular plug and jack in the Universal Service Order Codes (USOC)
and ANSI/TIA/EIA 570-B - ANSWER The placement of pair numbers 3 and 4
How is silver satin cable used to connect telephone equipment to wall outlets typically
pinned - ANSWER Reversed at opposite ends, or cross-pinned
In unshielded twisted pair (UTP) cable, what is the term that describes when an
information-carrying conductor makes contact with a grounded conductor - ANSWER
Ground Fault
, After resolving the problem with the premises wiring issue, which of the following is the
next step in the six-step process that the tech should take - ANSWER Verify that the
problem has been resolved and that phone service is running perfectly on all phones
If the telephone wiring is in the bus topology and the twisted-pair cable tester is
connected at the embedded multimedia terminal adapter (EMTA) with the remote unit
connected to the last outlet in the loop, what is the quickest way to locate the incorrectly
wired outlet if the tester indicates a wiring error? - ANSWER Break the loop into
smaller
sections and retest the two sections to identify which one has the wiring error. Continue
to divide the section with the error into smaller sections until the wiring error is identified
How should the digital multimeter (DMM) be used to troubleshoot problems in the
telephone wiring? - ANSWER Use the voltmeter function; both the network interface
device (NID) and the embedded multimedia terminal adapter (EMTA) provide a steady
on-hook voltage
What is it called when several computers are sharing files without a WAP - ANSWER
Ad-Hoc Mode
What is the standard encryption method used with WPA2 - ANSWER AES
When configuring a wireless router, why is changing the service set identifier (SSID)
from the device default recommended - ANSWER To avoid telling hackers exactly
what the device is
Which mode uses a wireless access point (WAP) connected to a wired network -
ANSWER Infrastructure
In regard to Wi-Fi networks, what is WPS used for - ANSWER To enable connection to
a Wi-Fi network without a Windows interface
Which encryption method is the most secure for a wireless network - ANSWER WPA2
How many channels are available with IEEE 802.11g - ANSWER 11
What is the last step of the basic wireless access point (WAP) setup - ANSWER Apply
Security
All 802.11 standards use one of two frequency bands. What are these frequency bands
- ANSWER 2.4 GHz and 5 GHz bands
What uses the 2.4 GHz band and runs at 54 Mbps - ANSWER 802.11g
100% Solutions
What does a set-top box (STB) diagnostic page of a quadrature amplitude
modulation(QAM) channel showing signal-to-noise ratio(SNR) near or below 30 dB
indicate - ANSWER the QAM channel quality is on the edge for reliable reception, and
the source of the problem is likely in the distribution network or customer premises
Which Data Over Cable Service Interface Specification (DOCSIS) layer is used by cable
modem termination system (CMTS) to differentiate between cable modems - ANSWER
the DOCSIS Media Access Control (MAC) Layer
What was introduced in Data Over Cable Service Interface Specification(DOCSIS) 3.0
to allow enough bandwidth for upstream carriers from previous DOCSIS versions -
ANSWER The option to increase the top frequency of the upstream to 85MHz
In a Data Over Cable Service Interface Specification (DOCSIS) network, why is the
data throughput over the return or upstream path typically less than the throughput of
data over the forward or downstream path - ANSWER Compared to the downstream
path, the narrower bandwidths and lower orders of modulation used to transport data
over the return path cause the downstream and upstream data throughput to be
unequal or asymmetrical
What would be the downstream throughput if two quadrature amplitude modulation
(QAM) channels with a throughput of 38 Mbps were bonded - ANSWER 76 Mbps
What are two features that were added in Data Over Cable Service Interface
Specification(DOCSIS) 3.1 to extend the viability of hybrid fiber/coax(HFC) network into
the next decade - ANSWER Orthogonal frequency division multiplexing(OFDM) and
low-density parity-check (LDPC)
How does Internet Protocol (IP) multicast differ from IP broadcast - ANSWER IP
multicast traffic is only sent to specific modem addresses on the network; IP broadcast
traffic is sent to all modems on the network
Which step in the troubleshooting process requires a discussion with the customer to
gather more detail about the problem - ANSWER Step 1: Identify the Problem
When analyzing a problem, what can the technician learn by asking the customer to
show or demonstrate the problem - ANSWER The symptoms of the problem can be
,viewed and any unusual screens or customer entries can be identified
When using a digital signal analyzer to troubleshoot data throughput in the Data Over
Cable Service Interface Specification (DOCSIS) network, what is the minimum
modulation error ratio(MER) into the cable modem for a 256-quadrature amplitude
modulation(QAM) carrier - ANSWER 32 dB or greater
What layers of the Open Systems Interconnection (OSI) reference model are specific to
cable networks and are present only between Data Over Cable Service Interface
Specification (DOCSIS) modems and the cable modem termination system (CMTS)? -
ANSWER Layers 1 through 4 (Physical layer, Data Link Layer, Network Layer, and
Transport Layer) are applied between the DOCSIS modem and CMTS
A customer reports a problem of no dial tone(NDT) Upon Inspection, the tech notices
that new carpenting has been installed. What should the tech do next - ANSWER Look
for a cable that runs under the carpet; it is likely that the cable has a short from the
carpeting tack strip
What is the likely problem when there is dial tone on one phone connected to an outlet,
but not on two other phones connected to two different outlets - ANSWER An open
circuit caused by a break in a conductor, poor contact in a modular connector, or an
incorrect wire connection
In the customer premises, what could cause some dual tone multifrequency (DTMF)
touch-tone telephones to have continuous dial tone caused by polarity reversal, but not
other DTMF telephones - ANSWER The telephone wiring polarity is incorrect, and the
customer has a mix of older and newer DTMF touch-tone telephones
What should be checked as a possible cause of hum on a customer's telephone line -
ANSWER Shielding problems in the station wiring, poor terminations, or poor
grounding and bonding connections
What is the difference between the wiring configurations for a residential 8-position,
8contact(8P8C) modular plug and jack in the Universal Service Order Codes (USOC)
and ANSI/TIA/EIA 570-B - ANSWER The placement of pair numbers 3 and 4
How is silver satin cable used to connect telephone equipment to wall outlets typically
pinned - ANSWER Reversed at opposite ends, or cross-pinned
In unshielded twisted pair (UTP) cable, what is the term that describes when an
information-carrying conductor makes contact with a grounded conductor - ANSWER
Ground Fault
, After resolving the problem with the premises wiring issue, which of the following is the
next step in the six-step process that the tech should take - ANSWER Verify that the
problem has been resolved and that phone service is running perfectly on all phones
If the telephone wiring is in the bus topology and the twisted-pair cable tester is
connected at the embedded multimedia terminal adapter (EMTA) with the remote unit
connected to the last outlet in the loop, what is the quickest way to locate the incorrectly
wired outlet if the tester indicates a wiring error? - ANSWER Break the loop into
smaller
sections and retest the two sections to identify which one has the wiring error. Continue
to divide the section with the error into smaller sections until the wiring error is identified
How should the digital multimeter (DMM) be used to troubleshoot problems in the
telephone wiring? - ANSWER Use the voltmeter function; both the network interface
device (NID) and the embedded multimedia terminal adapter (EMTA) provide a steady
on-hook voltage
What is it called when several computers are sharing files without a WAP - ANSWER
Ad-Hoc Mode
What is the standard encryption method used with WPA2 - ANSWER AES
When configuring a wireless router, why is changing the service set identifier (SSID)
from the device default recommended - ANSWER To avoid telling hackers exactly
what the device is
Which mode uses a wireless access point (WAP) connected to a wired network -
ANSWER Infrastructure
In regard to Wi-Fi networks, what is WPS used for - ANSWER To enable connection to
a Wi-Fi network without a Windows interface
Which encryption method is the most secure for a wireless network - ANSWER WPA2
How many channels are available with IEEE 802.11g - ANSWER 11
What is the last step of the basic wireless access point (WAP) setup - ANSWER Apply
Security
All 802.11 standards use one of two frequency bands. What are these frequency bands
- ANSWER 2.4 GHz and 5 GHz bands
What uses the 2.4 GHz band and runs at 54 Mbps - ANSWER 802.11g
