Operating Systems
(CIS 4020)
FINAL Exam Sample Questions

Answer SEVEN questions out of NINE.
You may have one personally prepared “review sheet” with you.

No computers, cell phones, calculators allowed EXCEPT:
If you type the exam:
You should log into ZOOM.
Join a breakout room
THEN share your screen, turn on your camera and microphone.
(If you are in the same room as other attendees, you may need to MUTE *and* turn your sound down to 0.)
Except for being in ZOOM, the computer should be only used for typing and submitting your written answers.

1.  Computer arithmetic: (h hex, d decimal, o octal, b binary)
Convert 151h to base 10.

Convert 101010001b to base 16.

Convert 521o to base 2.

Convert 337d to base 8.

In a two’s complement, 16 bit machine, what base 10 traditional number does FEDCh represent?
SHOW YOUR WORK!

2.  CPU Scheduling:

Identify two strategies for Main Memory scheduling.
Create a sequence of memory requests which illustrates the difference between the two.

3. Virtual Memory:
Describe the advantages and disadvantages of Virtual Memory.
Under what circumstances does Virtual Memory have a slower ‘through-put’ than a system without virtual memory?

4. Secondary Storage:

What methods can be used to minimize the delay of waiting for I/O to complete?

Describe at least 3.

5. Security:
List three major threats to Computer Security, and explain how an operating system can protect against them.

6. Virtual Machines

Compare the advantages and disadvantages of teaching an operating system class using physical versus virtual machines.

7. Distributed Systems.

What are the similarities and differences between a distributed operating system, and a computer network?

8. Computer representation of Information

The contents of a word in memory can be:
Integer
Character
Floating point
Machine language instruction
ASCII

How does the computer (hardware, OS, software) tell the difference between them during execution?

9. Overview

One of the goals for your education is to prepare you to “design solutions for broadly defined technical problems and assist with the engineering design of systems, components, or processes appropriate to the discipline.”

A. Identify topics covered in the ideal Operating Systems course, which help you prepare for the above goal, and how they prepare you for that goal.

B. In light of your answer above, EITHER 
Explain why Computer Science majors SHOULD be required to take an Operating Systems course,
OR
Explain why taking an Operating Systems Course SHOULD be ELECTIVE.

In either case, show that you understand the implication of understanding Operating Systems in a career in Computer Science.