What are 3 characteristics of sine waves?

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CCNA 1 v3.1
Module 4 Review
What describes frequency?
• number of cycles each second
2
What are 3 characteristics of
sine waves?
• They repeat the same pattern at
regular intervals.
• They occur naturally and change
regularly over time.
• No two adjacent points on a graph
have the same value.
3
What are 2 common ways in which
the capacities of communication
systems are measured?
• analog bandwidth
• digital bandwidth
4
What are 2 reasons why fiber optic
installations would be favored over
copper between buildings?
• attentuation properties
• no electrical interference
5
What are 2 ways binary ones and
zeros are represented in fiber
optic installations?
• light/no light
• increasing/decreasing light intensity
6
What are 3 factors that
contribute to attenuation in a
copper media?
• long cable lengths
• defective connectors
• energy leaks through the insulation of
the cable
7
What are 2 problems associated
with impedance mismatches in
copper cabling?
• jitter
• reflection
8
What are 2 conditions describing the
transmission of signals from one wire
pair which affects another wire pair?
• noise
• crosstalk
9
What type of wiring problem is
depicted in this sample of a
cable tester?
• an open
10
What 2 factors need to be
considered to limit the amount of
signal attenuation in long
Ethernet cable runs?
• Type of media
• Length of cable
11
What are 3 tests specified by the
TIA/EIA-568-B standard for copper
cable?
• wire map
• insertion loss
• propagation delay
12
What best describes
amplitude?
• The height of each wave
13
In a new network installation, the network
administrator has decided to use a
medium that is not affected by electrical
noise. Which cable type will best meet
this standard?
• fiber optic
14
Which of the following are
true concerning crosstalk?
(Choose three.)
• FEXT is less of a problem than is NEXT.
• Using frequency step sizes that are larger than those
specified by the TIA/EIA standard has no effect on link fault
detection.
• A cable with a NEXT measurement of 30 dB would be
considered a better cable than one which has a NEXT
measurement of 10 dB.
• NEXT needs to be measured from each pair to each other
pair in a UTP link, and from both ends of the link.
• FEXT is determined by injecting a signal into a pair of wires
and measuring the signal strength on the other end of the
same pair of wire.
15
Which frequencies are used by a
cable tester to measure
attenuation?
• the highest frequencies that the
cable is rated to support
16
What are 3 characteristics about
square waves?
• They repeat the same pattern at regular
intervals.
• They repeat the flat pattern on both the
top and bottom of the wave.
• They do not continuously vary with time.
17
What are 2 purposes of shielding
in copper based media?
• protect one pair of wires within the
cable from noise generated by
electrical signals on another pair of
wires
• protect the data signal from external
sources of noise
18
What are pulses and why are they
important in digital communication?
(Choose two.)
• irregular accidental spikes in energy levels
• determine the value of the data being transmitted
• create the timing mechanism for data transmission
• increases in energy which damage data
transmissions
• deliberate, fixed disturbances of predictable
duration
19
Two wires from different wire pairs
are connected to the wrong pins
on both ends of a cable. What is
the wire fault name for this
connection?
• Split-pair
20
What 3 issues are detected
by the wire map test?
• Opens
• Reversed-pair faults
• Short circuits
21
What cable test verifies
that all eight wires are
connected to the correct
pins on both ends of the
cable?
• Wire map test
22
To ensure reliable LAN
communications, what should
a technician be looking for
when attaching connectors to
the ends of UTP cable?
• The wire pairs remain twisted as
much as possible
23
What type of shielding does data
coaxial cable use?
• braided conductive
• foil-screened
24
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