ISRO COMPUTER SCIENCE - 2013 SET A (Q41 to Q60)

41 transmission time for a frame is 20ns and the propagation time is
30ns?
a 20%
b 25%
c 40%
d 66% v

42 vaS does not support which of the following addressing modes?
a unicast addressing
b multicast addressing
c broadcast addressing
d anycast addressing

43 What is IP class and number of sub-networks if the subnet mask is
255224.00?
a class A, 3
b class A, 8
c class B, 3
d class B, 32

44 Which algorithm is used to shape the bursty trafficinto a fixed rate
traffic by averaging the data rate?
a solid bucket algorithm
b spanning tree algorithm
c hocken helm algorithm
d leaky bucket algorithm

45 A packet filtering firewall can
a deny certain users from accessing a service
b block worms and viruses from entering the network
c disallow some files from being accessed through FTP
d block some hosts from accessing the network
 
46 Which of the following encryption algorithms is based on the Fiestal
struture?
a Advanced Encryption Standard
b RSA public key cryptographic algorithm
c Data Encryption Standard
d RC4
47 The protocol data unit for the transport layer in the internet stack is
a segment t ‘
b message
0 datagram
d frame ,
48 The Guass-Seidal iterative method can be used to solve which of
the following sets?
a Linear algebraic equations
b Linear and non-linear algebraic equations
0 Linear differential equations
d Linear and non-linear differential eqUations
49 What is the least value of the function f(x) = 2x2 - 8x - 3 in the
interval [0 ,5] ?
a -15
b 7
c -11
d -3
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COMPUTER SCIENCE — 2013 SET-A
50
Consider the following set of processes, with arrival times and the
required CPU-burst times given in milliseconds.
Process Arrival Time Burst Time
P1 0 ' 4
P2 2 2
P3 3 1
What is the sequence in which the processes are completed?
Assume round robin scheduling with a time quantum of 2
milliseconds.
a P1, P2, P3
b P2, P1, P3
c P3, P2, P1
d P2, P3, P1
51 In case of a DVD, the speed of data transfer is mentioned in
multi les of?
a 150 KB/s
b 1.38 MB/s
c 300 KB/s
d 2.40 MB/s
Suppose we have variable logical records of lengths of 5 bytes, 10
52 bytes, and 25 bytes while the physical block size in disk is 15 bytes.
What is the maximum and minimum fragmentation seen in bytes?
a 25 and 5
b 15 and 5
c 15 and 0
d 10 and 5
A CPU scheduling algorithm determines an order for the execution
53 of its scheduled processes. Given ‘n' processes to be scheduled on
one processor, how many possible different schedules are there?
a n
b n2
c n!
d 2n
54
Which of the following are the likely causes of thrashing?
Page size was very small
There are too many users connected to the system
QOU'Q)
Least recently used policy is used for page replacement
First in First out policy is used for page replacement
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COMPUTER SCIENCE — 2013
SET-A
Consider a logical address space of 8 pages of 1024 words each,
55 mapped onto a physical memory of 32 frames. How many bits are
there in the physical address and logical address respectively?
a 5, 3 r
b 10, 10
c 15, 13
d 15, 15
56 In a 64-bit machine, with 2 GB RAM, and 8 KB page size, how many
entries will be there in the page table if it is inverted?
a 218
b 220
c 233
d 251
57 Which of the following is not a necessary condition for deadlock?
a Mutual exclusion
b Reentrancy
0 Hold and wait
d No pre-emption
Consider the following process and resource requirement of each
process.
Type 1 Type 2
Process Used Max Used Max
58 P1 1 2 1 3
P2 1 3 1 2
P3 ’2 4 1 4
Predict the state of this system, assuming that there are a total of 5
instances of resource type 1 and 4 instances of resource type 2.
a Can go to safe or unsafe state based on sequence
b Safe state
0 Unsafe state
d Deadlock state >
A starvation free job scheduling policy guarantees that no job
59 indefinitely waits for a service. Which of the following job
scheduling policies is starvation free?
a Priority queing
b Shortest Job First
c Youngest Job First
d Round robin

60 The state of a process after it encounters an "O instruction is
a ready
b blocked
c idle '
d running