Requires all retransmission of the succeeding frame along with the lost or damaged frame

Error controlQuestions onError ControlNeed for Error controlThe goal of the data link layer is to provide reliable and error free communication betweenadjacent machines connected by a single communication channel. But during thetransmission, there may occur some errors.For example, frames may be lost or may bedamaged on the way. As a result, communication will not be reliable. So it is necessary todevise mechanism to detect errors and correct them. To achieve the above requirements,data link layer provides some error control techniques.These techniques are collectively known asautomatic repeat request (ARQ).These arediscussed in next section.Error Control TechniquesWhen an error is detected in a frame, the receiver sends a request to the transmitter toretransmit the damaged frame. The most popular retransmission scheme is known asAutomatic-Repeat-Request (ARQ). Such schemes, where receiver asks transmitter to re-transmit if it detects an error, are known as reverse error correction techniques. There existthree popular ARQ techniques, as shown in Figure 1.Figure 1: Error control techniquesStop-and-Wait ARQIt is based on the Stop-and-Wait flow control technique. In Stop-and-Wait ARQ, the sender(say station A) transmits a frame and then waits till it receives positive acknowledgement(ACK) or negative acknowledgement (NACK) from the receiver (say station B). Station Bsends an ACK if the frame is received correctly, otherwise it sends NACK. Station A sends anew frame after receiving ACK; otherwise it retransmits the old frame, if it receives a NACK.This is illustrated in Fig. 2.1

Error controlFigure 2:Stop-And-Wait ARQ techniqueTo tackle the problem of a lost or damaged frame, the sender is equipped with a timer. Incase of alost ACK, the sender transmits the old frame. In the Fig. 3, the second frame islost during transmission. The sender is unaware of this loss, but starts a timer after sendingeach frame. Normally an ACK frame is received before the timer expires. In this case no ACKis received, and the timer expires and starts retransmission of the same frame by thesender. The sender always starts a timer after the transmission, but in the secondtransmission receives an ACK frame before the timer expires. It indicates that the data hasnow been received by the remote node.

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Unit 2, Error detection and correction, Automatic repeat request, TEF, error control

(Last Updated On: December 4, 2020)

This is the MCQ in Data Link Control from the book Data Communications and Networking 4th Edition by Behrouz A. Forouzan. If you are looking for a reviewer in datacom, topic in Electronics Systems and Technologies (Communications Engineering) this will definitely help you before taking the Board Exam.In this particular topic you have learned Data link control that deals with the design and procedures for communication between two adjacent nodes: node-to-node communication. Data link control functions include framing, flow and error control, and software-implemented protocols that provide smooth and reliable transmission of frames between nodes. If you skip the summary visit Data Link Control .

Watch Audio MCQ in Data Link Control

Practice Exam Test Questions

Choose the letter of the best answer in each questions.

1. In Go-Back-N ARQ, if 5 is the number of bits for the sequence number, then the maximum size of the receive window must be _______.

A)   1

B)   15

C)   16

D)   31

View Answer:

Answer: Option A

Solution:

2. In Go-Back-N ARQ, if frames 4, 5, and 6 are received successfully, the receiver may send an ACK _______ to the sender.

A)   6

B)   7

C)   5

D)   any of the above

View Answer:

Answer: Option B

Solution:

3. The Stop-And-Wait ARQ, Go-Back-N ARQ, and the Selective Repeat ARQ are for ______ channels.

A)   noiseless

B)   noisy

C)   either (a) or (b)

D)   neither (a) nor (b)

View Answer:

Answer: Option B

Solution:

4. The _________Protocol, adds a simple error control mechanism to the _______Protocol.

A)   Selective Repeat ARQ; Go-Back-N ARQ

B)   Go-Back-N ARQ; Stop-and-Wait

C)   Stop-and-Wait ARQ; Stop-and-Wait

D)   none of the above

View Answer:

Answer: Option C

Solution:

5. In PPP, the ________ is responsible for establishing, maintaining, configuring, and terminating links.

A)   PAP

B)   CHAP

C)   LCP

D)   NCP

View Answer:

Answer: Option C

Solution:

6. HDLC is an acronym for _______.

A)   Half-duplex digital link combination

B)   Host double-level circuit

C)   High-duplex line communication

D)   High-level data link control

View Answer:

Answer: Option D

Solution:

7. In Selective Repeat ARQ, if 5 is the number of bits for the sequence number, then the maximum size of the receive window must be _____.

A)   1

B)   15

C)   16

D)   31

View Answer:

Answer: Option C

Solution:

8. In Go-Back-N ARQ, if 5 is the number of bits for the sequence number, then the maximum size of the send window must be _____.

A)   1

B)   15

C)   16

D)   31

View Answer:

Answer: Option D

Solution:

9. In Stop-and-Wait ARQ, the acknowledgment number always announces in ______ arithmetic the sequence number of the next frame expected.

A)   modulo-m

B)   modulo-2

C)   modulo-4

D)   none of the above

View Answer:

Answer: Option B

Solution:

10. In Selective Repeat ARQ, if 5 is the number of bits for the sequence number, then the maximum size of the send window must be _____.

A)   1

B)   15

C)   16

D)   31

View Answer:

Answer: Option C

Solution:

11. _______ control refers to a set of procedures used to restrict the amount of data that the sender can send before waiting for acknowledgment.

A)   Flow

B)   Error

C)   Transmission

D)   none of the above

View Answer:

Answer: Option A

Solution:

12. In the Go-Back-N Protocol, if the size of the sequence number field is 8, the sequence numbers are in ________ arithmetic,

A)   modulo-256

B)   modulo- 8

C)   modulo-2

D)   none of the above

View Answer:

Answer: Option A

Solution:

13. ______ control refers to methods of error detection and correction.

A)   Flow

B)   Error

C)   Transmission

D)   none of the above

View Answer:

Answer: Option B

Solution:

14. In a Go-Back-N ARQ, if the window size is 63, what is the range of sequence numbers?

A)   1 to 63

B)   1 to 64

C)   0 to 63

D)   0 to 64

View Answer:

Answer: Option C

Solution:

15. Both Go-Back-N and Selective-Repeat Protocols use a _________.

A)   sliding window

B)   sliding frame

C)   sliding packet

D)   none of the above

View Answer:

Answer: Option A

Solution:

16. In _________, the configuration is balanced. The link is point-to-point, and each station can function as a primary and a secondary.

A)   ARM

B)   ABM

C)   NBM

D)   NRM

View Answer:

Answer: Option B

Solution:

17. Byte stuffing means adding a special byte to the data section of the frame when there is a character with the same pattern as the ______.

A)   trailer

B)   flag

C)   header

D)   none of the above

View Answer:

Answer: Option B

Solution:

18. The ______ Protocol has neither flow nor error control.

A)   Selective-Repeat ARQ

B)   Go-Back-N ARQ

C)   Stop-and-Wait

D)   Simplest

View Answer:

Answer: Option D

Solution:

19. The most common protocol for point-to-point access is the Point-to-Point Protocol (PPP), which is a _________protocol.

A)   byte-oriented

B)   bit-oriented

C)   character-oriented

D)   none of the above

View Answer:

Answer: Option A

Solution:

20. For Stop-and-Wait ARQ, for 10 data packets sent, _______ acknowledgments are needed.

A)   less than 10

B)   more than 10

C)   exactly 10

D)   none of the above

View Answer:

Answer: Option C

Solution:

21. _________framing uses two categories of protocols: character-oriented and bit-oriented.

A)   Standard

B)   Fixed-size

C)   Variable-size

D)   None of the above

View Answer:

Answer: Option C

Solution:

22. _______ control refers to a set of procedures used to restrict the amount of data that the sender can send before waiting for acknowledgment.

A)   Flow

B)   Error

C)   Transmission

D)   none of the above

View Answer:

Answer: Option A

Solution:

23. In a ________ protocol, the data section of a frame is a sequence of characters.

A)   bit-oriented

B)   character-oriented

C)   either (a) or (b)

D)   none of the above

View Answer:

Answer: Option B

Solution:

24. In _______ framing, there is no need for defining the boundaries of frames.

A)   standard

B)   fixed-size

C)   variable-size

D)   none of the above

View Answer:

Answer: Option B

Solution:

25. The _______Protocol has both flow control and error control.

A)   Stop-and-Wait

B)   Selective-Repeat ARQ

C)   Go-Back-N ARQ

D)   both (b) and (c)

View Answer:

Answer: Option D

Solution:

26. In _________, the station configuration is unbalanced. We have one primary station and multiple secondary stations.

A)   ARM

B)   NBM

C)   NRM

D)   ABM

View Answer:

Answer: Option C

Solution:

27. In a _________ protocol, the data section of a frame is a sequence of bits.

A)   bit-oriented

B)   byte-oriented

C)   either (a) or (b)

D)   none of the above

View Answer:

Answer: Option A

Solution:

28. In ________ framing, we need a delimiter (flag) to define the boundary of two frames.

A)   standard

B)   fixed-size

C)   variable-size

D)   none of the above

View Answer:

Answer: Option C

Solution:

29. High-level Data Link Control (HDLC) is a _______ protocol for communication over point-to-point and multipoint links.

A)   byte-oriented

B)   bit-oriented

C)   character-oriented

D)   none of the above

View Answer:

Answer: Option B

Solution:

30. Bit stuffing means adding an extra 0 to the data section of the frame when there is a sequence of bits with the same pattern as the ________.

A)   trailer

B)   flag

C)   header

D)   none of the above

View Answer:

Answer: Option B

Solution:

31. In the _________Protocol, if no acknowledgment for a frame has arrived, we resend all outstanding frames.

A)   Go-Back-N ARQ

B)   Selective-Repeat ARQ

C)   Stop-and-Wait ARQ

D)   none of the above

View Answer:

Answer: Option A

Solution:

32. The Simplest Protocol and the Stop-and-Wait Protocol are for ______ channels.

A)   noiseless

B)   noisy

C)   either (a) or (b)

D)   neither (a) nor (b)

View Answer:

Answer: Option A

Solution:

33. The _______Protocol has flow control, but not error control.

A)   Selective-Repeat ARQ

B)   Stop-and-Wait

C)   Simplest

D)   Go-Back-N ARQ

View Answer:

Answer: Option B

Solution:

34. In Stop-and-Wait ARQ, we use sequence numbers to number the frames. The sequence numbers are based on __________arithmetic.

A)   modulo-m

B)   modulo-2

C)   modulo-4

D)   none of the above

View Answer:

Answer: Option B

Solution:

35. In the _____ Protocol, the sender sends its frames one after another with no regard to the receiver.

A)   Simplest

B)   Selective-Repeat ARQ

C)   Stop-and-Wait

D)   Go-Back-N ARQ

View Answer:

Answer: Option A

Solution:

36. _________control in the data link layer is based on automatic repeat request, which is the retransmission of data.

A)   Flow

B)   Error

C)   Transmission

D)   none of the above

View Answer:

Answer: Option B

Solution:

37. In PPP, _______ is a three-way hand-shaking authentication protocol in which the password is kept secret; it is never sent online.

A)   PAP

B)   LCP

C)   NCP

D)   CHAP

View Answer:

Answer: Option D

Solution:

38. In PPP, ________ is a simple authentication procedure with a two-step process:

A)   CHAP

B)   PAP

C)   LCP

D)   NCP

View Answer:

Answer: Option B

Solution:

39. In the _________ protocol we avoid unnecessary transmission by sending only frames that are corrupted.

A)   Selective-Repeat ARQ

B)   Stop-and-Wait ARQ

C)   Go-Back-N ARQ

D)   none of the above

View Answer:

Answer: Option A

Solution:

40. In ________ protocols, we use ________.

A)   byte-oriented; bit stuffing

B)   bit-oriented; bit stuffing

C)   character-oriented; bit stuffing

D)   none of the above

View Answer:

Answer: Option B

Solution:

41. In the _____ Protocol, the sender sends one frame, stops until it receives confirmation from the receiver, and then sends the next frame.

A)   Simplest

B)   Stop-and-Wait

C)   Selective-Repeat ARQ

D)   Go-Back-N ARQ

View Answer:

Answer: Option B

Solution:

42. Stop-and-Wait ARQ is a special case of Go-Back-N ARQ in which the size of the send window is ___.

A)   1

B)   2

C)   8

D)   none of the above

View Answer:

Answer: Option A

Solution:

43. ARQ stands for _______.

A)   Acknowledge repeat request

B)   Automatic retransmission request

C)   Automatic repeat quantization

D)   Automatic repeat request

View Answer:

Answer: Option D

Solution:

44. _______ in the data link layer separates a message from one source to a destination, or from other messages going from other sources to other destinations.

A)   Controlling

B)   Framing

C)   Digitizing

D)   none of the above

View Answer:

Answer: Option B

Solution:

45. Data link control deals with the design and procedures for ______ communication.

A)   node-to-node

B)   process-to-process

C)   host-to-host

D)   none of the above

View Answer:

Answer: Option A

Solution:

46. In _________ protocols, we use ________.

A)   bit-oriented; character stuffing

B)   character-oriented; bit stuffing

C)   character-oriented; byte stuffing

D)   none of the above

View Answer:

Answer: Option C

Solution:

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What requires all retransmission of the succeeding frame along with the lost or damaged frame?

What is the transmission of damaged or lost frames in the data link layer?

What are the three phases of error control?

Which layer is responsible for frame error detection?