Computer Networks CS 457 NAME_______________

Spring 1997 FINAL EXAM Dr. Wayne Summers

Read each question carefully before you answer. Work at a steady pace, and you should have ample time to finish. Make sure your name is on your paper before you turn it in.

I. Multiple Choice: Write the letter of the best answer.

_____ 1. A method of managing terminals where several terminals share the same

line and the central computer alternately asks each terminal if it has a message to

send is called

a) multiplexing b) concentration

c) polling d) contention

e) none of these

_____ 2. FDM depends upon dividing up bandwidth into

a) several frequencies b) formats

c) stop and start bits d) cycles

e) none of these

_____ 3. A major advantage of fiber-optic transmission is its

a) sensitivity b) bandwidth

c) low cost d) ease of installation

e) all of these

_____ 4. The datagram mode is part of the following layer:

a) Physical b) Data

c) Network d) Transport

e) Presentation

_____ 5. A block of characters sent over a communications line is called a

a) Batch b) Frame

c) Group d) Byte

e) header

_____ 6. In the ______ topology, each node has equal access to a single line, much like a highway.

a) star b) ring

c) bus d) tree

e) mesh

_____ 7. Which of the following LANs uses the IEEE 802.3 standard?

a) Compunet b) Micronet

c) Tokenet d) Ethernet

_____ 8. A ring and a bus are examples of

a) LAN capacity b) LAN protocol

c) LAN topology d) intelligence electronics

_____ 9. The set of rules governing the flow of information in a network is called

a) encryption b) multiplexing

b) protocol d) modem menu

e) packet switching

_____ 10. The device which determines the most efficient path to transmit messages in a network and then sends the data along that path

a) gateway b) router

c) bridge d) repeater

e) none of these

_____ 11. The media type is determined at the __________ Layer of the OSI model

a) Physical b) Data Link

c) Network d) Transport

e) none of these

_____ 12. Protocols for FTP would be part of the _________ Layer of the OSI model.

a) Physical b) Data Link

c) Network d) Transport

e) none of these

_____ 13. Addressing of packets of data takes place at the _________ Layer of the OSI model.

a) Physical b) Data Link

c) Network d) Transport

e) none of these

_____ 14. Which of the following is not a reason for networking computers?

a) sharing hardware resources b) sharing files

c) sharing software d) e-mailing

e) none of these

_____ 15. Which layer of the OSI model converts transmitted data into an appropriate display format like ASCII?

a) Application b) Session

c) Presentation d) Transport

e) Physical

II. Answer completely the following questions.

16. Draw a model of the OSI model matching internetworking devices and protocols to the corresponding OSI layer.(15 pts)

17. You are interviewing for a job as a communications manager for ABC Corp., a small manufacturing company in Albuquerque. The interviewer notices that you have taken a course in Computer Networks. He asks you to answer the following questions.

a) Briefly describe five important concepts that you learned in the course. (10 pts)

i)

ii)

iii)

iv)

v)

b) In what areas of computer networks do you need further training? (5 pts)

i) What is NT and how is it used?

ii) You mentioned that you have been exposed to Windows 95 and Windows for WorkGroups. Briefly describe the differences between the three versions of Windows that you have seen.

d. Currently ABC Corp. uses a solitary IBM minicomputer with 10 terminals used primarily for standard data processing applications. Each of their 5 departments have 2-5 PCs used mainly for wordprocessing and spreadsheet applications. Describe how computer networks can make his company more competitive in the near future.

(10 pts)

18. a) Describe what hardware is needed for a Netday and how each is used.(10 pts)

b) Describe ways that we can improve the quality of education for students in the public schools in Las Vegas, NM., by using computer networks.(10 pts)

III. Answer completely 5 of the following seven questions. (10 pts each)

19. You've just tried to install a computer running Windows 95 on the Internet. When you try to execute Netscape and Telnet, they do not work. List some of the things you would check? How would you fix the problem?

20. a) What is a modem?

b) List and describe the different modulation techniques.

21. List and describe the different hardware devices used for internetworking. Be sure to indicate in which layer of the OSI model each device is used.

22. a) Give an example of a peer-to-peer network.

b) Give an example of a client-server network.

c) What is the difference between a peer-to-peer network and a client-server network?

d) When would you use a peer-to-peer network?

e) When would you use a client-server network?

23. a) Name and describe 2 IEEE 802 standards.

b) Name and describe 2 X. standards.

24. a) What exactly does an NIC do?

2. What are NDIS and ODI and why are they important?

c) What is NETBIOS and what role does it play?

25. a) What is the Internet?

b) What is an intranet?

c) Name and describe three(3) protocols used with the Internet.

III. Answer completely 5 of the following six questions. (10 pts each)

26. A company has seven administrative buildings scattered over the 30-acre grounds of its world headquarters and several customer service centers around the country. Describe three ways this company might use computer networks to enhance its day-to-day operations.

a)

b)

c)

27. Using your knowledge of network topology and network OS services, draw a diagram that illustrates a network that meets the following requirements. An office building of five offices is to be networked. Each office will have three PCs and one dot matrix printer. There will be one laser printer attached to the file server. Use the figure below to draw in the network cable and lines indicating how the computers and printers will be wired. Assume there is ceiling space to run all the cable.

75 feet

What type of network topology did you use? Why?

28. Your boss has just read an article about ISDN and although he doesn't know what it is, thinks the company should use it.

a) Explain to your boss what ISDN is in simple terms that he can understand.

b) Describe some of the benefits of ISDN to your boss.

c) Explain some concerns you might have about using ISDN in your company.

29. a) What is PCS?

2. What are some of the key challenges to PCS deployment?

3. What are some of the important benefits of such a telecom environment?

30. Explain ATM + SONET = B-ISDN.

31. a) Explain and contrast cell-relay and frame-relay.

2. Explain and contrast circuit switching and packet switching.

BONUS: You been asked to help redesign this course (Computer Networks):

a. Describe briefly which topic you would leave out. (5 pts)

b. Describe briefly which topic you would include that was not covered in class or should have been covered more. (5 pts)