Computer Science for IGCSE & O level - Data Transmission (Section 4)

  • 1
    Which error detection method is best suited for data transfer over noisy channels?
    Хариулт
    (B)
    Checksum
  • 2
    What is the function of a 'repeater' in a network?
    Хариулт
    (B)
    To amplify and regenerate signals to extend network range.
  • 3
    Which of the following best describes the concept of 'firewall'?
    Хариулт
    (B)
    A device that filters network traffic.
  • 4
    What best describes the role of a 'hub' in a network?
    Хариулт
    (B)
    Connects devices and broadcasts data to all connected devices.
  • 5
    In the ARQ process, how are errors detected?
    Хариулт
    (D)
    By calculating a checksum on the data before transmission.
  • 6
    Which of the following best describes how data is transferred using parallel data transmission?
    Хариулт
    (C)
    Data is sent multiple bits at a time over several wires.
  • 7
    Which of the following can be applied on both serial and parallel data transmission?
    Хариулт
    (D)
    All of the above.
  • 8
    In a network, what does the term 'node' typically refer to?
    Хариулт
    (B)
    A device that forwards data packets.
  • 9
    What does the acronym 'DNS' stand for?
    Хариулт
    (B)
    Domain Name System
  • 10
    What is the primary role of the receiver in an ARQ system?
    Хариулт
    (C)
    To acknowledge received data or request retransmission.
  • 11
    In the context of a USB connection, what happens when a new device is detected?
    Хариулт
    (C)
    The device is automatically recognized and the appropriate device driver software is loaded.
  • 12
    If a byte uses even parity, and the byte received is 10110010, what should the parity bit be?
    Хариулт
    (A)
    0
  • 13
    What does the 'Presentation Layer' do in the OSI Model?
    Хариулт
    (C)
    Formats and encrypts data.
  • 14
    What is the difference between even parity and odd parity?
    Хариулт
    (A)
    Even parity means the number of 1s in the byte is even; odd parity means the number of 1s in the byte is odd.
  • 15
    What is the purpose of the 'session layer' in the OSI model?
    Хариулт
    (B)
    To manage connections between applications.
  • 16
    In the context of error detection, what is a checksum used for?
    Хариулт
    (B)
    To detect errors in the data transmission.
  • 17
    What is the difference between simplex and duplex transmission?
    Хариулт
    (A)
    Simplex sends data in one direction, duplex in both directions.
  • 18
    What advantage does packet switching provide for networks?
    Хариулт
    (B)
    More efficient use of network resources.
  • 19
    Which of the following statement(s) is/are true regarding Quantum cryptography?
    Хариулт
    A
    D
  • 20
    Which of the following is an advantage of packet switching?
    Хариулт
    (C)
    Can easily re-route data if a line fails.
  • 21
    What is the purpose of 'port numbers' in networking?
    Хариулт
    (B)
    To uniquely identify an application or service running on a device.
  • 22
    What is the purpose of a 'protocol' in networking?
    Хариулт
    (B)
    To establish rules for communication between devices.
  • 23
    What is the purpose of error detection in data transmission?
    Хариулт
    (C)
    To identify transmission errors.
  • 24
    What is the key advantage of asymmetric encryption over symmetric encryption?
    Хариулт
    (D)
    Key exchange is more secure
  • 25
    If the 'hop number' of a packet reaches zero, what action is usually taken?
    Хариулт
    (C)
    The packet is discarded.
  • 26
    What is the difference between 'static' and 'dynamic' IP addresses?
    Хариулт
    (B)
    Static IP addresses are permanent; dynamic IP addresses can change.
  • 27
    Which of the following is true about the polarization of the photon?
    Хариулт
    B
    D
  • 28
    Which error detection method involves adding all the 1s in the payload and storing it as a value in the trailer?
    Хариулт
    (B)
    Checksums.
  • 29
    Which of the following factors affect data transmission protocol?
    Хариулт
    A
    B
    C
  • 30
    What is the main purpose of parity checking in data transmission?
    Хариулт
    (B)
    To detect errors that may have occurred during transmission.
  • 31
    In data transmission, which of the following is NOT a typical method for error detection?
    Хариулт
    (C)
    Encryption
  • 32
    In data transmission, what does the term 'Simplex' refer to?
    Хариулт
    (C)
    Sending data in only one direction.
  • 33
    When using ARQ, if an error is detected, what typically happens?
    Хариулт
    (B)
    The receiver sends a NAK to the sender.
  • 34
    What is the name of the process of converting the encrypted message back to a readable form?
    Хариулт
    (B)
    Decryption
  • 35
    Which of the following is a key benefit of packet switching?
    Хариулт
    (B)
    More efficient use of network bandwidth.
  • 36
    What does a 'tag number' (hop number) do to the header of a packet?
    Хариулт
    (A)
    It reduces it by one
  • 37
    Which technology is specifically based on the use of quantum physics principles?
    Хариулт
    (B)
    Quantum cryptography.
  • 38
    Which data is usually included in an error detection method?
    Хариулт
    A
    B
    C
  • 39
    Which error-detection method is best suited for identifying burst errors (multiple bits corrupted)?
    Хариулт
    (B)
    Checksum
  • 40
    What is the main goal of encryption?
    Хариулт
    (B)
    To convert the data into an unreadable format.
  • 41
    Which of the following is a form of error detection that makes use of a system of acknowledgements and timeouts?
    Хариулт
    (A)
    Automatic repeat request
  • 42
    What is a 'subnet mask' used for?
    Хариулт
    (B)
    To identify the network portion of an IP address.
  • 43
    Which of the following are essential parts of a data packet?
    Хариулт
    A
    B
    C
  • 44
    What is the role of a "check digit"?
    Хариулт
    (B)
    To detect errors in data entry.
  • 45
    What is the main advantage of using checksums for error detection over a simple parity check?
    Хариулт
    (A)
    Checksums can detect multiple-bit errors more effectively.
  • 46
    In the context of data transmission, what does "duplex" refer to?
    Хариулт
    (C)
    The ability to send and receive data simultaneously.
  • 47
    What does the term 'URL' stand for?
    Хариулт
    (B)
    Uniform Resource Locator
  • 48
    Which part of a data transmission system is most vulnerable to errors?
    Хариулт
    (C)
    The transmission medium.
  • 49
    What is the purpose of the 'physical layer' in the OSI model?
    Хариулт
    (C)
    To define the physical transmission media.
  • 50
    Which security threat involves an attacker attempting to guess a password or key through trial and error?
    Хариулт
    (B)
    Brute-force attack