Chapter 5 Review (Data Communications)
Why do APC ferrules create less back reflection than do UPC ferrules?
The end faces are placed at an angle to eachother
Which kind of multiplexing assigns slots to nodes according to priority and need? a. WDM (wavelength division multiplexing) b. STDM (statistical time division multiplexing) c. TDM (time division multiplexing) d. CWDM (coarse wavelength division multiplexing)
b. STDM ( Statistical time division multiplexing)
What kind of cable uses BNC connectors? Which connector is likely to be used by cable TV? a. Coaxial cable, F-connector b. Twisted-pair cable, RJ-11 c. Copper cable, RJ-45 d. Fiber-optic cable, MTRJ
a. Coaxial cable, F connector
Which fiber connector contains two strands of fiber in each ferrule? a. MTRJ b. SC c. ST d. LC
a. MTRJ
Suppose you're assisting with a cable installation using fiber optic cabling that will support Gigabit Ethernet. You're approved to install segments up to 4000m n length. What kind of cable are you using?
A single mode fiber cable
What fiber is used in fiber-optic cabling to protect the inner core and prevent the cable from stretching?
Kevlar
What is the difference between short circuits and open circuits?
Short circuit is an unwanted connection, ie. Exposed wires touching. Open circuit is one where needed connections are missing, ie. Wire breaks
Why is SMF more efficient over long distances than MMF?
Signals traveling over MMF experience greater attenuation than those on SMF
How is latency measured and in what unit?
RTT (round trip time), Millie seconds
Which fiber transceiver is the same size as SFP transceivers, but can support network speeds over 10 Gbps?
SFP+
What kind of tool can measure the distance to the location of damage in a cable?
Cable performance tester
What characteristic of optical transmissions is primarily responsible for the distance limitations of fiber optic cabling?
Cost and Optical loss
What is twist ratio, and why is it important?
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.
Suppose you're creating path cables to be used in a government office. What color wire goes in the first pin? a. White/orange b. White/green c. Brown d. Blue
b. White/Green
Which of these categories of twisted pair cable can support Gigabit Ethernet? a. Cat 5, Cat 6, Cat 7 b. Cat 5e, Cat 6, Cat 3 c. Cat 5e, Cat 6a, Cat 7 d. Cat 6, Cat 7a, Cat 5
c. Cat 5e, Cat 6a, Cat 7
What is the earliest twisted pair cabling standard that meets the minimum requirements for 10GBase-T transmission? a. Cat 5e b. Cat 5 c. Cat 6a d. Cat 7
c. Cat 6a
What type of fiber cable problem us caused when pairing a 50-micron core cable with a 62.5-micron cable? a. Dirty connectors b. Wavelength mismatch c. Fiber type mismatch d. TX/RX reverse
c. Fiber type mismatch
Which part of a toner and probe kit emits an audible tone when it detects electrical activity on a wire pair? a. TDR b. Tone generator c. Tone locator d. Toner
c. Tone locator
Which transmission characteristic is never fully achieved? a. Latency b. Throughput c. Bit rate d. Bandwidth
d. Bandwidth
Which kind of crosstalk occurs between wire pairs near the source of the signal? a. Alien b. TX/RX reverse c. FEXT d. NEXT
d. NEXT
