Đề 8 – Đề thi, câu hỏi trắc nghiệm online Truyền số liệu

1. Which of the following is an advantage of using time-division multiplexing (TDM) in data transmission?

A. Lower susceptibility to noise and interference.

B. More efficient use of bandwidth by allocating time slots to different users or devices.

C. Higher data transfer rates compared to frequency-division multiplexing (FDM).

D. Simpler implementation compared to other multiplexing techniques.

2. Which of the following is a disadvantage of parallel data transmission compared to serial data transmission?

A. Lower data transfer rates.

B. Higher susceptibility to crosstalk and timing skew.

C. More complex encoding and decoding schemes.

D. Inability to transmit data over long distances.

3. In the context of data transmission, what is 'jitter'?

A. The amount of data transmitted per unit of time.

B. The variation in delay of data packets.

C. The strength of the transmitted signal.

D. The type of modulation used.

4. What is the role of a codec in data transmission?

A. To control the flow of data between two devices.

B. To convert data signals from one form to another, often for compression or standardization.

C. To manage the routing of data packets across a network.

D. To provide a secure connection between two devices.

5. What is the main advantage of using fiber optic cables for data transmission?

A. Lower installation costs.

B. Higher resistance to electromagnetic interference.

C. Easier to tap into for unauthorized access.

D. Lower bandwidth capacity compared to copper cables.

6. Which of the following is a disadvantage of using wireless data transmission?

A. Lower data transfer rates compared to wired transmission.

B. Higher cost of infrastructure deployment.

C. Greater susceptibility to interference and security risks.

D. Limited mobility of devices.

7. In the context of data transmission, what does 'bandwidth' refer to?

A. The physical size of the transmission cable.

B. The range of frequencies that a transmission channel can carry.

C. The power consumption of the transmitting device.

D. The geographical distance over which the data can be transmitted.

8. What is the purpose of forward error correction (FEC) in data transmission?

A. To prevent unauthorized access to the data.

B. To correct errors at the receiver without retransmission.

C. To reduce the size of the data being transmitted.

D. To increase the speed of data transmission.

9. What is the key difference between FDM (Frequency Division Multiplexing) and TDM (Time Division Multiplexing)?

A. FDM is used for digital signals, while TDM is used for analog signals.

B. FDM divides the channel into frequency slots, while TDM divides the channel into time slots.

C. FDM is more susceptible to interference than TDM.

D. FDM requires synchronization, while TDM does not.

10. Which of the following is a characteristic of asynchronous data transmission?

A. Requires a shared clock signal between sender and receiver.

B. Data is transmitted in a continuous stream.

C. Each character is transmitted with start and stop bits.

D. Higher data transfer rates compared to synchronous transmission.

11. Which of the following is a characteristic of synchronous data transmission?

A. Data is transmitted with start and stop bits.

B. Requires precise timing synchronization between sender and receiver.

C. Suitable for transmitting small amounts of data intermittently.

D. Each character is transmitted independently.

12. Which of the following is a common cause of data loss during transmission?

A. High bandwidth availability.

B. Strong signal strength.

C. Electromagnetic interference.

D. Efficient data compression techniques.

13. Which error detection method can detect burst errors most effectively?

A. Parity Check.

B. Checksum.

C. Cyclic Redundancy Check (CRC).

D. Simple Repetition.

14. Which type of modulation technique is most resistant to noise?

A. Amplitude Modulation (AM).

B. Frequency Modulation (FM).

C. Phase Modulation (PM).

D. Quadrature Amplitude Modulation (QAM).

15. Which of the following is a characteristic of serial data transmission?

A. Multiple bits are sent simultaneously over separate wires.

B. Data is transmitted one bit at a time over a single channel.

C. Data is transmitted in packets with error-checking codes.

D. Data is transmitted wirelessly using radio waves.

16. Which of the following is a characteristic of half-duplex data transmission?

A. Data can be transmitted in both directions simultaneously.

B. Data can be transmitted in only one direction.

C. Data can be transmitted in both directions, but only one direction at a time.

D. Data is transmitted using multiple channels simultaneously.

17. Which of the following is the primary function of a modem in data transmission?

A. To amplify the signal strength for long-distance transmission.

B. To convert digital signals to analog signals and vice versa for transmission over telephone lines.

C. To filter out unwanted noise and interference from the data signal.

D. To encrypt the data signal for secure transmission.

18. What is the purpose of Cyclic Redundancy Check (CRC) in data transmission?

A. To encrypt the data for secure transmission.

B. To compress the data to reduce bandwidth usage.

C. To detect errors in the transmitted data.

D. To automatically retransmit lost data packets.

19. What is the purpose of interleaving in data transmission?

A. To encrypt the data for secure transmission.

B. To spread data bits across multiple time slots or frequencies to mitigate burst errors.

C. To compress the data to reduce bandwidth usage.

D. To increase the signal strength of the transmitted data.

20. What is the purpose of spread spectrum techniques in data transmission?

A. To encrypt the data for secure transmission.

B. To compress the data to reduce bandwidth usage.

C. To spread the signal over a wider frequency band to reduce interference and improve security.

D. To increase the data transfer rate over a channel.

21. What is the purpose of channel coding in data transmission?

A. To compress the data to reduce the required bandwidth.

B. To encrypt the data for security purposes.

C. To introduce redundancy into the data stream to detect and correct errors.

D. To convert the data into a format suitable for transmission over a specific medium.

22. Which of the following is an example of a simplex data transmission mode?

A. A telephone conversation.

B. A walkie-talkie communication.

C. A radio broadcast.

D. A computer network communication.

23. Which of the following is a method to improve security during data transmission?

A. Increasing the bandwidth of the channel.

B. Using shielded cables.

C. Implementing encryption techniques.

D. Reducing the transmission power.

24. What is the purpose of data compression in data transmission?

A. To encrypt data for security.

B. To reduce the size of the data to be transmitted.

C. To increase the reliability of the data.

D. To convert analog signals to digital signals.

25. What is the role of a demultiplexer in data transmission?

A. To combine multiple data streams into a single stream for transmission.

B. To separate a single data stream into multiple streams at the receiving end.

C. To amplify the signal strength of the data being transmitted.

D. To encrypt the data for secure transmission.

26. What is the purpose of ARQ (Automatic Repeat Request) in data transmission?

A. To automatically adjust the transmission frequency.

B. To automatically request retransmission of data packets that are detected as erroneous.

C. To automatically compress the data before transmission.

D. To automatically encrypt the data for secure transmission.

27. What is the function of a bridge in data transmission?

A. To convert digital signals to analog signals.

B. To connect two networks that use different protocols.

C. To filter and forward data packets between network segments based on MAC addresses.

D. To amplify the signal strength of the data being transmitted.

28. In data transmission, what does 'latency' refer to?

A. The rate at which data is transmitted over a channel.

B. The delay between sending and receiving data.

C. The amount of bandwidth available on a channel.

D. The physical distance between the sender and receiver.

29. What is the role of a repeater in data transmission?

A. To convert digital signals to analog signals.

B. To amplify and regenerate a signal to extend its transmission distance.

C. To route data packets to their destination.

D. To filter out noise from the data signal.

30. What is the primary function of a router in data transmission?

A. To convert analog signals to digital signals.

B. To amplify the signal strength of the data being transmitted.

C. To route data packets between different networks based on IP addresses.

D. To filter out noise from the data signal.