UNIVERSITY EXAMINATIONS: 2012/2013
EXAMINATION FOR THE BACHELOR OF SCIENCE IN
INFORMATION TECHNOLOGY
BIT 1106 OPERATING SYSTEM
DATE: AUGUST, 2013 TIME: 2 HOURS
INSTRUCTIONS: Answer Question ONE and any other TWO
QUESTION ONE
a) Explain the following terms:
i) Clock Interrupt [2Marks]
ii) Trap [2 Marks]
iii) Device driver [2 Marks]
iv) Critical race condition [3 Marks]
b) Describe the function of the kernel in process management. [5 Marks]
c) Briefly explain five factors to consider when selecting a file design method
[5 Marks]
d) Identify five principles of I/O software [5 Marks]
e) Discuss six functions of virtual memory. [6 Marks]
QUESTION TWO
a) Briefly describe each of the following terms as used in paging.
i) Page fault [2 Marks]
ii) Virtual address space [2 Marks]
iii) Physical address space [2 Marks]
b) With the aid of a diagram, explain the concept of segmentation as used in
memory management scheme. [3 Marks]
c) Describe the objectives of I/O management. [5 Marks]
d) Discuss the following scheduling algorithms
i) Multi-level queue [2 Marks]
ii) Event driven [2 Marks]
iii) FCFS [2 Marks]
QUESTION THREE
a) Explain the following terms with respect to scheduling and performance
maximization:
(i) Throughput [2 Marks]
(ii) Turnaround time [2 Marks]
(iii) Response time [2 Marks]
b) With the aid of a diagram discuss the five process state in operating systems.
[5 Marks]
c) Give the benefits of Direct Memory Access (DMA) in I/O device management.
[4 Marks]
d) Briefly explain five factors that may lead to a process switch. [5 Marks]
QUESTION FOUR
a) Explain the following with reference to file management;
i) file security [2 Marks]
ii) file integrity [2 Marks]
iii) File map [2 Marks]
b) Give the benefits of using directories in the file system [6 Marks]
c) Discuss in detail four file organization methods. [8 Marks]
QUESTION FIVE
a) Security goals of any computer system are decided by its security policies.
Briefly explain three computer security goals that can be set in an operating
system. [6 Marks]
b) State four types of security threats to consider when designing and implementing
any operating system. [4 Marks]
c) Discuss the objectives of I/O management. [8 Marks]
d) Describe device controller. [2 Mark]
