Computer Network : Data Link Layer (Test 1) : Free online Test by Teachexam

Question : What is the purpose of bit stuffing in framing?

Increase data size

Prevent confusion with frame delimiters

Improve speed

Encrypt data

Question : Which statement correctly differentiates flow control and error control?

Both deal only with speed control

Flow control handles errors, error control handles speed

Flow control manages transmission rate, error control ensures accuracy

Both are unrelated

Question : Which technique is commonly used in error control to ensure reliable transmission?

Byte stuffing

Automatic Repeat Request (ARQ)

Time Division Multiplexing

Frequency Division Multiplexing

Question : In flow control, what is the main role of the receiver?

To increase transmission speed

To send data continuously

To regulate sender’s data rate

To detect errors only

Question : Which of the following best describes the primary purpose of framing in data link control?

To control transmission speed

To divide bit stream into identifiable units

To detect transmission errors

To encrypt data

Question : What is the main purpose of adding redundant bits in error correction?

Increase data transmission speed

Reduce bandwidth usage

Detect and locate errors in transmitted data

Compress the data

Question : In Hamming code, redundant bits are placed at positions:

Prime numbers

Odd numbers only

Powers of 2

Multiples of 3

Question : Which of the following statements about parity bits is correct?

A single parity bit can correct errors

Parity bits cannot detect any errors

A single parity bit can detect but not correct errors

Parity bits are not used in Hamming code

Question : What is the minimum number of redundant bits (r) required for d data bits in Hamming code?

r = d + 1

2ʳ = d + r

2ʳ ≥ d + r + 1

r = log₂(d)

Question : Which of the following correctly distinguishes Forward Error Correction (FEC) from Backward Error Correction?

FEC requires retransmission, while backward correction does not

FEC automatically corrects errors at receiver side

Both require retransmission

Backward correction uses redundant bits

Question : What is the primary purpose of adding redundant bits in error detection techniques?

To compress data

To increase transmission speed

To verify data integrity during transmission

To encrypt data

Question : Which of the following statements about Two-Dimensional Parity Check is correct?

It detects all types of errors

It cannot detect errors if identical bit positions are corrupted in multiple rows

It uses polynomial division

It does not use redundancy

Question : Which error detection method is considered most powerful for detecting burst and random errors?

Single Parity Check

Two-Dimensional Parity

Checksum

Cyclic Redundancy Check (CRC)

Question : In Checksum error detection, when is the received data considered valid?

When the sum of segments is maximum

When the complemented sum equals zero

When parity bits match

When remainder is non-zero

Question : Which of the following techniques can only detect single-bit errors and fails when two bits are altered?

Checksum

Cyclic Redundancy Check (CRC)

Single Parity Check

Two-Dimensional Parity Check

Question : In Data Link Layer communication, what is the role of error detection?

Correct errors automatically

Identify errors in transmitted frames

Route packets efficiently

Compress data

Question : Which of the following protocols operates at the Data Link Layer?

HTTP

IP

Ethernet

TCP

Question : Which mechanism prevents the sender from overwhelming the receiver in the Data Link Layer?

Error detection

Flow control

Framing

Routing

Question : What is the main purpose of framing in the Data Link Layer?

Dividing data into packets

Adding logical addresses

Encapsulating network layer data into frames

Encrypting the data

Question : Which of the following is the primary function of the Data Link Layer?

Routing data across multiple networks

Reliable transmission between directly connected nodes

End-to-end communication between applications

Data encryption