M.C.A. (Science) (Semester-II) (CBCS) Examination, 2017
OPERATING SYSTEM
Day Date: Monday, 24-04-2017 Max. Marks: 70
Time: 10.30 AM to 01.00 PM
Instructions
Q.1 and Q.2 are compulsory questions.
Attempt any Three Questions from Q.3 to Q.7
Figures to right indicate full makrs.
Q.1 A Choose the correct alternative 10
A vulnerability of firewalls is spoofing, in which an
unauthorized host pretends to be host by meeting
some criterion.
Invader Workstation machine E
Authorized Server
The provides the means for proper use of hardware,
software and data in the question of the computer system.
Hardware system Computer tool E
I/O devices Operating system
Time sharing requires interactive computer system, which
provides communication between the user and the
system.
Direct Indirect E
Simplex Easy
The list of processes waiting for a particular is called a
Each has its own queue.
Mailbox Device E
Circular Multilevel
Cooperative processes require an inter-process
communication mechanism that will allow them to exchange

Data and information Text section E
Lists Program Counter
SJF scheduling is sometimes called shortest-remainingtime-
first scheduling.
Page 2 of 3
Shortest Job Finish Non-preemptive E
Preemptive Gantt Chart
allocation, each file is a list of disk blocks;
the disk blocks may be scattered anywhere on the dist.
Contiguous Linked E
Double ended None of these
graph, it can be shown that, if the graph contains no
cycles, then no process in the system is deadlocked.
Processor allocation Resource allocation E
Mutual exclusion Transaction management
Paging involves breaking logical memory into blocks of the
same size called
Frames Fragments E
Segments Pages
10) Priority scheduling algorithm can leave some priority
processes waiting indefinitely.
High Medium E
Low None of these
State True or False 04
A volatile storage loses its contents when the power to the
device is removed.
The sequence of directories searched when a file is
named, this operation is called search path.
The virtual memory abstracts main memory into a large,
uniform array of storage, separating logical memory as
viewed by the user from physical memory.
A single threaded process has one program counter
specifying the next instructions to execute.
Q2 Write a short note 08
i. Critical Region
ii. PCB
Answer the following 06
i. What do you mean by Swapping?
ii. Define the term File.
Q3 Answer the following 07
Explain different kinds of fragmentation with suitable example?
Discuss working of First in First Out page replacement algorithm
for given below reference string having 03 frames for allocation.
Reference string
6
07
Page 3 of 3
Q4 Answer the following
Explain mechanism of Round Robin scheduling for processes
given below
07
PID Name Burst Time Time Quantum
101 ABC 20 minute
05 Minute
102 XYZ 05 minute
103 PQR 15 minute
104 MNO 10 minute
State the meaning of allocation methods. Discuss various kinds
of allocation method in file system implementation.
07
Q5 Answer the following
State the meaning of Demand Paging. Explain in detail various
step to handle a page fault?
07
Explain in detail working of First Come, First Served algorithm
when a Disk head is positioned at 85.
Queue 95, 38, 81, 49, 64, 102, 51, 55, 68, 72, 12
07
Q6 Answer the following
What do you mean by virus? Discuss in detail different kinds of
virues to cause a program threat.
07
Explain in detail principle of process synchronization for handling
producer-consumer problem?
07
Q7 Answer the following
What do you mean by Multiprocessor time sharing systems?
Differentiate between Distributed OS and Network OS?
07
Define the term Safe and Unsafe state. Discuss in detail methods
to detect deadlock?