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1. Parallel data is best described as:

a) All bits are sent at the same time.
b) One bit is sent at a time.
c) The data represented in analog form.
d) None of the above

2. What is the primary disadvantage of a point-to-point (peer-to-peer) network?

a) Complicated protocol is required.
b) The security of such a network is very poor.
c) Possible high cost per unit, due to low communications line utilization.
d) None of the above

3. Before a unit can transmit a message on a ring network, what must it first do?

a) Transmit a request to send
b) Acquire the token
c) Wait for permission from the host
d) None of the above

4. Which of these is a modulation process?

a) Analog to digital conversion in a modem receiver
b) Digital-to-analog conversion in a modem
c) Converting parallel data to serial data
d) None of the above

5. Which of these is best described by the term demodulation?

a) Analog to digital conversion in a modem receiver
b) Digital-to-analog conversion in a modem
c) Converting parallel data to serial data
d) None of the above

6. Before a terminal can transmit a message on a multidrop network, what must it first do?

a) Acquire the token
b) Transmit a request to send
c) Wait for the host to send it a poll message
d) None of the above

7. Who or what acts as the controller or "boss" in a multidrop network?

a) The first terminal on the network
b) The system administrator
c) The host computer
d) None of the above

8. What is a primary fault of single-level modulation systems?

a) They are slow and don't use bandwidth efficiently
b) They use excessive bandwidth
c) They are very sensitive to noise
d) None of the above

9. Which modulation method below changes the frequency of the carrier in order to represent the data?

a) FSK
b) ASK
c) PSK
d) None of these

10. Which of the below factors limits the number of bits per transition in practical communication systems?

a) Channel power gain
b) Channel bandwidth
c) Channel S/N ratio
d) None of the above

11. If the signalling rate is 600 BAUD and the constellation is as shown above, what will the actual data rate be?

a) 4800 BPS
b) 2400 BPS
c) 1200 BPS
d) None of these

12. How many bits are encoded per transition in the figure above?

a) 1
b) 2
c) 3
d) None of the above

13. A modulator has an input data rate of 2400 BPS and encodes three bits per transition. Under these conditions, it uses up 1000 Hz of bandwidth. What will happen to the bandwidth if the data rate is reduced to 1200 BPS (and everything else stays the same)?

a) The bandwidth will remain exactly the same
b) The bandwidth will double
c) The bandwidth will become 750 Hz
d) None of the above

14. If a certain modulator produces a change in the carrier every 1 mS, what is the resulting signalling rate?

a) 500 BAUD
b) 1000 BAUD
c) 2000 BAUD
d) None of the above

15. How many bits are encoded per transition in the figure above?

a) 1
b) 2
c) 3
d) None of the above

16. The fundamental units of digital information flow are:

a) BAUD
b) CPS
c) BPS
d) None of the above

17. A certain system has 8 modulation states and has an input data rate of 2400 BPS. What will the resulting signalling rate be?

a) 1200 BAUD
b) 2400 BAUD
c) 800 BAUD
d) None of the above

18. Which of these is a method of impressing information onto a carrier wave?

a) Amplitude modulation (AM)
b) Frequency modulation (FM)
c) Phase modulation (PM)
d) All of the above
e) None of the above

19. The rate at which changes are made to an analog carrier wave is called the _______?

a) BPS
b) CPS
c) BAUD
d) None of the above

20. A certain system has 16 modulation states and has a signalling rate of 600 BAUD. What will the resulting data rate be?

a) 1200 BPS
b) 2400 BPS
c) 4800 BPS
d) None of the above

21. What is the primary effect of dispersion in a fiber optic cable?

a) Decreases the available signal at the receiver
b) Decreases the available bandwidth
c) Sharpens the rising and falling edges of data waveforms
d) None of these

22. What is the meaning of the term 'numerical aperture'?

a) Ease of getting light into the fiber
b) Decibel loss per unit length in the fiber
c) Ease of splicing the fiber
d) None of the above

23. What is the acceptance cone angle for a fiber optic cable built with a core index N1=1.5, and a cladding index N2=1.45?

a) 30 degrees
b) 22.5 degrees
c) 11.25 degrees
d) None of these

24. Why isn't modal dispersion a problem in single-mode fiber optics?

a) Light moves through these by reflection instead of refraction
b) Single-mode fiber optics can only be used for short-length runs
c) Only one light path is possible in a single-mode fiber
d) None of these

25. What is the speed of light in a material with an index of refraction of 2.0?

a) 150,000,000 m/s
b) 200,000,000 m/s
c) 300,000,000 m/s
d) None of these

26. When a clock is sent with data, it is called ______ data.

a) Asynchronous
b) Synchronous
c) Digital
d) None of the above

27. What type of data is sent without a clock signal?

a) Asynchronous
b) Synchronous
c) Analog
d) None of the above

28. In the figure above, the parameters are 8,N,2 and the bit time is 500 uS. How many characters can be sent per second?

a) 125
b) 136
c) 181.8
d) None of the above

29. Given that the parameters are 8,N,1 above, what hex data value is being sent?

a) $F3 (0xF3)
b) $A5 (0xA5)
c) $AF (0xAF)
d) None of the above

30. Given that the parameters are 8,N,1 above, what hex data value is being sent?

a) $AB (0xAB)
b) $D3 (0xD3)
c) $D5 (0xD5)
d) None of the above

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