CORE CONCEPTS VERIFIED SOLUTIONS
BRIEF
◉ What was introduced in 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
85
MHZ.
◉ In a 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 QAM
channels with a throughput of 38 Mbps were bonded?
,Answer: 76 Mbps.
◉ What are two features that were added in DOCSIS 3.1 to
extend the viability of HFC networks into the next decade?
Answer: OFDM and LDPC.
◉ 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 im the DOCSIS network, what is the minimum MER
into the cable modem for a 256-QAM carrier?
Answer: 32 dB or greater
,◉ How should the digital multimeter (DMM) be used to
troubleshoot problems in the telephone wiring?
Answer: Use tie voltmeter fumction, both the network interface
device
(NID) and the embedded multimedia terminal adapter (EMTA)
provide a steady On-hook voltage.
◉ 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.
◉ After resolving the problem with the premises wiring issue, which
of the following is the next step in the six-step process that the
technician should take?
Answer: Verify that the problem has been resolved and that phone
service
is running perfectly on all phones.
◉ 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
◉ How is silver satin cable used to connect telephone
equipment to wall outlets typically pinned?
Answer: D) Reversed at opposite ends, or cross-pinned.
◉ What is the difference between the wiring configurations for a
residential, 8-position, 8-contact (8P8C) modular plug and jack
in the Universal Service Order Codes (USC) and
ANSI/TIA/EIA 570-B?
Answer: The placement of pair numbers 3 and 4.
◉ 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.
◉ 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