In the name of ALLAH, the most beneficient, the most merciful

Data Communication (CS601)

Multiple Choice Questions (MCQs)

Objective Questions

  1. In CRC there is no error if the remainder at the receiver is _______.

    1. Equal to the remainder at the sender
    2. Zero
    3. Nonzero
    4. The quotient at the sender
  2. What is the period of a Sine wave having frequency of 2 Hz?

    1. 0.2
    2. 0.1
    3. 0.5
    4. 0.3
  3. The transmission medium that carries the message is referred to as the ___________.

    1. send and receive device
    2. communication channel
    3. protocol
    4. gateways
  4. The inversion of the level at 1 bit is called as ________.

    1. NRZ-L
    2. NRZ-I
    3. RZ
    4. None of the given.
  5. Analog signals are refers to be ___________

    1. Continuous
    2. Discrete
    3. Periodic
    4. Aperiodic
  6. Baud rate is greater than or equal to the bit rate.

    1. True
    2. False
  7. In Synchronous TDM, Time slots are not same in number as input devices.

    1. True
    2. False
  8. Quantization is a method of assigning ________ values in a specific range to sampled instances.

    1. Negative
    2. Positive
    3. Binary
    4. Integral
  9. Which of the following is most affected by noise?

    1. PSK
    2. ASK
    3. FSK
    4. QAM
  10. In ASK, Noise usually affects the ________.

    1. Amplitude
    2. Phase
    3. Sample
    4. Frequency
  11. BSC supports ___________ transmission using ___________ flow control.

    1. Full-duplex, Stop and wait ARQ
    2. Half-duplex, Selective reject ARQ
    3. Full-duplex, Selective reject ARQ
    4. Half-duplex, Stop and wait ARQ
  12. Which layer is concerned with the syntax and semantics of info exchange between two systems?

    1. Physical
    2. Application
    3. Session
    4. Presentation
  13. The __________ generates the data and passes it along with any control information to a __________.

    1. DTE, DCE
    2. DCE, DTE
    3. DTE, DTE
    4. DCE, DCE
  14. In ________, both peak amplitude and frequency remains constant as the phase changes.

    1. PSK
    2. QAM
    3. Both PSK & QAM
    4. None of the given
  15. Which of the following consist of just one redundant bit per data unit?

    1. Two dimentional Parity check.
    2. CRC
    3. Simple Parity Check
    4. Checksum
  16. AM signal requires ___________ the BW of original signal

    1. Twice
    2. Half
    3. Same
    4. Three Times
  17. Following characteristics fully describe ___________,
    Amplitude
    Period/Frequency
    Phase

    1. Sine Waves
    2. Digital Signals
    3. Aperiodic Signals
    4. None of the given
  18. Digital signals are refered to be ___________.

    1. Continuous
    2. Discrete
    3. All of the given
    4. None of the given
  19. Which error detection method consists of a parity bit for each unit as well as an entire data unit of parity bits?

    1. Checksum
    2. Cyclic Redundancy Check (CRC)
    3. Longitudinal Red Check (LRC)
    4. Vertical Redundancy Check (VRC)
  20. Central Hub in a Tree is an ___________.

    1. Active hub
    2. passive hub
  21. A portion of the path that carries TX between a given pair of devices is known as ___________.

    1. Direct Point
    2. Bridge
    3. Channel
    4. Access Point
  22. A ___________ modem is used to connect two DTEs directly.

    1. 'NULL
    2. Cable
    3. DSL
    4. None of the given
  23. What is the frequency of a sine wave if it completes one cycle in 5 seconds?

    1. 0.5
    2. 0.6
    3. 0.3
    4. 0.2
  24. Digitizing an Analog Signal is called ___________.

    1. Analog-to-Digital Conversion
    2. Digital-to-Digital Conversion
    3. Digital-to-Analog Conversion
    4. None of the given
  25. Analog refers to something that is continuous in ___________.

    1. Time
    2. Space
    3. Frequency
    4. None of the given
  26. In ASK, both ______ and ________ remain constant.

    1. Amplitude, Frequency
    2. Amplitude, phase
    3. Frequency, Phase
    4. Amplitude, Samples
  27. Time domain plot show changes in signal phase with respect to time.

    1. true
    2. false
  28. Like 10 Base 5, 10 Base 2 is a ________ topology LAN.

    1. Ring
    2. Mesh
    3. Star
    4. Bus
  29. PSK is susceptible to the noise degradation.

    1. True
    2. False
  30. Flow control is needed to prevent ________.

    1. Bit errors
    2. Overflow of the sender buffer
    3. Overflow of the receiver buffer
    4. Collision between sender and receiver
  31. Which level of the TCP/IP reference model routes data/information across a network channel?

    1. Application Layer
    2. Data Link Layer
    3. Transport Layer
    4. Network Layer
  32. What is the frequency of a sine wave if it completes one cycle in 2 seconds?

    1. 0.5
    2. 0.6
    3. 0.3
    4. 0.2
  33. There are __________types of guided media.

    1. 2
    2. 3
    3. 4
    4. 5
  34. Analog To Analog Conversion Methods include ___________.

    1. AM, PM and FM
    2. AM, FSK and PM
    3. AM, PM and QAM
    4. None of the given
  35. At the CRC generator, ___________ added to the data unit before the divisional process.

    1. 0s are
    2. 1s are
    3. a polynomial is
    4. a CRC remainder is
  36. ___________ is the rate of change with respect to time.

    1. Voltage
    2. Time
    3. Frequency
    4. Amplitude
  37. In _________, a signal is directed straight from antenna to antenna.

    1. Line of sight propagation
    2. Ground propagation
    3. Space propagation
    4. Tropospheric propagation
  38. What is the Bandwidth of a periodic signal if it is decomposed into 4 sine waves with frequencies 300, 600, 900 and 1200?

    1. 100
    2. 900
    3. 300
    4. 600
  39. Asynchronous transmission is ___________.

    1. Slow
    2. Fast
    3. Costly
    4. None effective
  40. Is there any difference between Data communication and telecommunication are network?

    1. Yes
    2. No
  41. By using ___________ system, change in the file contents during file transmission can be avoided.

    1. Routing
    2. Flow Control
    3. Error Detection and Correction
    4. Congestion Control
  42. The inversion of the level represents a 1 bit in ______ encoding

    1. NRZ-I
    2. NRZ-L
    3. RZ
    4. Manchester
  43. Which one is not the function of data link layer?

    1. Line discipline
    2. Flow control
    3. Error control
    4. Network control
  44. ___________ contains a repeater.

    1. Active hub
    2. Passive hub
  45. If the window size is 63 in go-back N ARQ then what is the range of sequence number?

    1. 0 to 63
    2. 0 to 64
    3. 1 to 63
    4. 1 to 64
  46. In line discipline after the data transmission, the sending system finishes with an ________ frame.

    1. EOT
    2. EKT
    3. ENT
    4. ESP
  47. ___________ encoding is almost obsolete today

    1. Bipolar
    2. Unipolar
    3. Polar
    4. None of the given
  48. In analog transmission, the base signal is called the________.

    1. Carrier Signal
    2. Analog signal
    3. Digital signal
    4. Modulated signal
  49. There are _________ types of serial transmission.

    1. 3
    2. 4
    3. 2
    4. None of the given
  50. In ___________ a dedicated communication path is established between two stations through the nodes of the network

    1. Circuit switching
    2. Packet switching
  51. If users must take turns using the link, then it is called Spatial Sharing.

    1. true
    2. false
  52. The term _______means that only one bit of a given data unit is changed from 1 to 0 or from 0 to 1.

    1. Packet Error
    2. Burst Error
    3. Single Bit Error
    4. Character Error
  53. Radio is an example of _______ signal conversion.

    1. Analog to analog
    2. Analog to digital
    3. Digital to Digital
    4. Digital to analog
  54. What is the Bandwidth of a periodic signal if it is decomposed into 4 sine waves with frequencies 200, 400, 600 and 800?

    1. 100
    2. 500
    3. 300
    4. 600
  55. In selective-reject ARQ, only the specific damaged or lost frame is ________.

    1. Retransmitted
    2. Forwarded
    3. Selected
    4. Rejected
  56. STP is more expensive than UTP and is less susceptible to noise.

    1. True
    2. False
  57. What is the period of a Sine wave having frequency of 10 Hz?

    1. 0.2
    2. 0.1
    3. 0.5
    4. 0.3
  58. Like Data link layer, ___________ is also responsible for Flow control.

    1. Transport Layer
    2. Session Layer
  59. TROPOSHERE is the layer of atmosphere above the troposhere but below space

    1. True
    2. False
  60. Each computer on the Internet has a unique numeric address called a(n) ___________.

    1. domain address
    2. protocol address
    3. IP address
    4. Web address
  61. Data is transmitted using light through a ___________ cable.

    1. twisted pair
    2. fiber-optic
    3. coaxial
    4. microwave
  62. A broadcast signal is received by the orbiting satellites which rebroadcasts ___________.

    1. to the resender
    2. to the sender
    3. to the atmosphere
    4. none of the given
  63. WDM stands for _________.

    1. Wave Division Multiplexing
    2. Wrong Division Multiplexing
    3. Well Division Multiplexing
    4. West Division Multiplexing
  64. Two or more computers connected so that they can communicate with each other and share information is called a ___________.

    1. satellite
    2. protocol
    3. broadcast
    4. network
  65. A sine wave is ___________.

    1. periodic and discrete
    2. aperiodic and discrete
    3. periodic and continuous
    4. aperiodic and continuous
  66. YMODEM has ________ Byte of data unit.

    1. 1024
    2. 256
    3. 128
    4. 512
  67. Asynchronous TDM is efficient only when the size of the time slot is kept relatively ___________.

    1. Large
    2. Small
    3. Medium
    4. Zero
  68. At the CRC checker, ___________ means that the data unit is damaged.

    1. A string of 0s
    2. A string of 1s
    3. A string of alternating 1s and 0s
    4. A nonzero remainder
  69. Which of the following sublyer resolves the contention for the shared media.

    1. MAC
    2. LLC
    3. Physical
    4. None of the given.
  70. The Internet is ___________.

    1. software for sending e-mail around the world
    2. a government-owned agency that links computers
    3. a global network of computers networks
    4. a specialised form of local area network
  71. A sine wave is defined by ___________ characteristics.

    1. 2
    2. 3
    3. 4
    4. 5
  72. To make sure that source does not overwhelm destination by sending data faster than it can be handled and processed is called?

    1. Addressing & Routing
    2. Exchange Management
    3. Flow Control
    4. Recovery
  73. Terminal, microprocessor, computer, printer or any other device that generates or consumes digital data is known as ___________

    1. DCE
    2. DTE
    3. DCE & DTE
    4. None of the given
  74. In the encoding where positive to negative transition is one and vice versa is zero.

    1. Manchester
    2. Differential Manchester
    3. All of the given
    4. None of given
  75. Line Configuration refers to the way two or more devices attach to a ___________.

    1. Path
    2. Circuit
    3. Link
    4. Router
  76. RZ stands for ___________.

    1. Return to Z
    2. Retire a Zero
    3. Return ot Zero
    4. None of the given
  77. dB is negative if a signal is ___________.

    1. Attenuated
    2. Distorted
    3. Amplified
    4. Noisy
  78. What is the period of a Sine wave having frequency of 5 Hz?

    1. 0.2
    2. 0.1
    3. 0.5
    4. 0.3
  79. Session layer is responsible for _________.

    1. Reassembly of data
    2. Maintaining the connection
  80. ___________ of a signal is the collection of all the component frequencies it contains.

    1. Time domain
    2. Frequency domain
    3. Frequency spectrum
    4. None of the given
  81. Human voice is example of ___________ signal.

    1. Digital
    2. Analog
    3. Discrete
    4. None of the given
  82. Radio wave transmission utilizes ___________ different types of propagation.

    1. Two
    2. Three
    3. Four
    4. Five
  83. Sampling means measuring ____________ of signal at equal intervals

    1. Amplitudes
    2. Frequencies
    3. Phases
    4. None of the given
  84. Which error detection method uses one's complement arithmetic.

    1. Cyclic Redundancy Check (CRC)
    2. Longitudinal Red Check (LRC)
    3. Checksum
    4. Simple Parity Check
  85. In OSI model headers are added at layer _________.

    1. 1,2,3 only
    2. 6,5,7 only
    3. 5,4,3 only
    4. 6,5,4,3,2 only
  86. Traditionally MANs have been implemented using one of the 2 technologies, Circuit Switching and Packet Switching

    1. true
    2. false
  87. There are three types of Hubs that exist. Which of the following options correctly describes these three?

    1. Passive, dormant, special
    2. Active , dormant , passive
    3. Passive, Active, Turbo
    4. Passive, Active, Intelligent
  88. Time domain shows changes in ___________.

    1. time w.r.t signal amplitude
    2. signal amplitude w.r.t time
    3. time
    4. All of the given
  89. The level of signal is always positive in NRZ encoding.

    1. true
    2. false
  90. Encoding digital data into digital signals is called ___________.

    1. Analog-to-Digital Conversion
    2. Digital-to-Digital Conversion
    3. Digital-to-Analog Conversion
    4. None of the given
  91. Which of the following statement is correct?

    1. Digital signals are less prone to Noise
    2. Digital signals are highly prone to Noise
    3. Analog Signals are less prone to Noise
    4. Digital signals are not affected by Noise