# Forouzan: MCQ in Multiple Access

(Last Updated On: December 28, 2017)

This is the MCQ in Multiple Access from book the 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 Multiple Access. At this point, we can say that Data link layer divided into two functionality-oriented sublayers. The upper sublayer is responsible for data link control, and the lower sublayer is responsible for resolving access to the shared media. If you skip the summary visit Multiple Access .

#### Begin and Good luck!

Choose the letter of the best answer in each questions.

1.In _______, the stations share the bandwidth of the channel in time.

A)   FDMA

B)   CDMA

C)   TDMA

D)   none of the above

Solution:

2. In ______, the chance of collision can be reduced if a station senses the medium before trying to use it.

A)   CSMA

B)   MA

C)   CDMA

D)   FDMA

Solution:

3. In the _______ method, the stations in a network are organized in a logical ring.

A)   polling

B)   token passing

C)   reservation

D)   none of the above

Solution:

4. In _______, the sequences are generated using orthogonal codes such the Walsh tables.

A)   TDMA

B)   CDMA

C)   FDMA

D)   none of the above

Solution:

5. __________ augments the CSMA algorithm to detect collision.

A)   CSMA/CD

B)   CSMA/CA

C)   either (a) or (b)

D)   both (a) and (b)

Solution:

6. In the _________ method, after the station finds the line idle, it sends its frame immediately. If the line is not idle, it continuously senses the line until it finds it idle.

A)   p-persistent

B)   nonpersistent

C)   1-persistent

D)   none of the above

Solution:

7. In the _____ method, time is divided into intervals. In each interval, a reservation frame precedes the data frames sent in that interval.

A)   token passing

B)   reservation

C)   polling

D)   none of the above

Solution:

8. In the _______ method, each station has a predecessor and a successor.

A)   token passing

B)   polling

C)   reservation

D)   none of the above

Solution:

9. The vulnerable time for CSMA is the ________propagation time.

A)   three times

B)   two times

C)   the same as

D)   none of the above

Solution:

10. In the _________ method, a special packet called a ______ circulates through the ring.

A)   polling: poll request

B)   token passing: token

C)   reservation: control frame

D)   none of the above

Solution:

11. The maximum throughput for pure ALOHA is ________ per cent.

A)   36.8

B)   18.4

C)   12.2

D)   none of the above

Solution:

12. In ________, the available bandwidth is divided into frequency bands.

A)   TDMA

B)   CDMA

C)   FDMA

D)   none of the above

Solution:

13. In ___________ methods, no station is superior to another station and none is assigned the control over another.

A)   controlled access

B)   random access

C)   channelization

D)   none of the above

Solution:

14. In the ________method, a station that has a frame to send senses the line. If the line is idle, it sends immediately. If the line is not idle, it waits a random amount of time and then senses the line again.

A)   1-persistent

B)   nonpersistent

C)   p-persistent

D)   none of the above

Solution:

15. In ______, each station is allocated a band to send its data. In other words, each band is reserved for a specific station, and it belongs to the station all the time.

A)   CDMA

B)   FDMA

C)   TDMA

D)   none of the above

Solution:

16. In the _______method, after the station finds the line idle it sends or refrain from sending based on the outcome of a random number generator. If the line is busy, it tries again.

A)   p-persistent

B)   nonpersistent

C)   1-persistent

D)   none of the above

Solution:

17. To avoid collisions on wireless networks, ________was invented.

A)   CSMA/CD

B)   CSMA/CA

C)   either (a) or (b)

D)   both (a) and (b)

Solution:

18. In _____, each station is allocated a time slot during which it can send data. Each station transmits its data in its assigned time slot.

A)   TDMA

B)   CDMA

C)   FDMA

D)   none of the above

Solution:

19. In the _______ method, the primary device controls the link; the secondary devices follow its instructions.

A)   token passing

B)   reservation

C)   polling

D)   none of the above

Solution:

20. In _____, each station transmits its data in its assigned time slot.

A)   TDMA

B)   CDMA

C)   FDMA

D)   none of the above

Solution:

21. We discussed ________ channelization protocols.

A)   four

B)   three

C)   two

D)   none of the above

Solution:

22. In the ______ method, all data exchanges must be made through the primary device even when the ultimate destination is a secondary device.

A)   polling

B)   token passing

C)   reservation

D)   none of the above

Solution:

23. We discussed ______ popular controlled-access methods.

A)   four

B)   three

C)   two

D)   none of the above

Solution:

24. In __________, each station is forced to send only at the beginning of the time slot.

A)   pure ALOHA

B)   slotted ALOHA

C)   both (a) and (b)

D)   neither (a) nor (b)

Solution:

25. In _______ methods, the stations consult one another to find which station has the right to send.

A)   channelization

B)   random access

C)   controlled access

D)   none of the above

Solution:

26. In ________ each station sends a frame whenever it has a frame to send.

A)   slotted ALOHA

B)   pure ALOHA

C)   both (a) and (b)

D)   neither (a) nor (b)

Solution:

27. In ______, the stations use different codes to achieve multiple access.

A)   CDMA

B)   TDMA

C)   FDMA

D)   none of the above

Solution:

28. In _______, collisions are avoided through the use of three strategies: the interframe space, the contention window, and acknowledgments.

A)   CSMA/CD

B)   CSMA/CA

C)   either (a) or (b)

D)   both (a) and (b)

Solution:

29. In the ________ method, a station needs to make a reservation before sending data. Time is divided into intervals.

A)   token passing

B)   polling

C)   reservation

D)   none of the above

Solution:

30. In pure ALOHA, the vulnerable time is ______ the frame transmission time.

A)   two times

B)   three times

C)   the same as

D)   none of the above

Solution:

31. The maximum throughput for slotted ALOHA is ________ per cent.

A)   36.8

B)   18.4

C)   12.2

D)   none of the above

Solution:

32. _________ is a multiple-access method in which the available bandwidth of a link is shared in time, frequency, or through code, between different stations.

A)   Controlled access

B)   Channelization

C)   Random access

D)   none of the above

Solution:

33. ________ requires that each station first listen to the medium before sending.

A)   FDMA

B)   CDMA

C)   MA

D)   CSMA

Solution:

34. We have categorized access methods into _______ groups.

A)   five

B)   three

C)   four

D)   two

Solution:

35. In _______ methods, a station cannot send unless it has been authorized by other stations.

A)   controlled access

B)   channelization

C)   random access

D)   none of the above

Solution:

36. In slotted ALOHA, the vulnerable time is ______ the frame transmission time.

A)   two times

B)   three times

C)   the same as

D)   none of the above

Solution:

37. In ________, a station monitors the medium after it sends a frame to see if the transmission was successful. If so, the station is finished. If, however, there is a collision, the frame is sent again.

A)   CSMA/CD

B)   CSMA/CA

C)   either (a) or (b)

D)   both (a) and (b)

Solution:

38. _______ is based on coding theory and uses sequences of numbers called chips.

A)   TDMA

B)   CDMA

C)   FDMA

D)   none of the above

Solution: