Information Technology Practice Questions

1 A subnet has been assigned a subnet mask of 255.255.255.192. What is the maximum number of hosts that can belong to this subnet?
A) 14
B) 30
C) 62
D) 126
Answer : (C)

2 Which one of the following is NOT shared by the threads of the same process ?
A) Stack
B) Address Space
C) File Descriptor Table
D) Message Queue
Answer : (A)

3 Let G be a weighted undirected graph and e be an edge with maximum weight in G. Suppose there is a minimum weight spanning tree in G containing the edge e. Which of the following statements is always TRUE?
A) There exists a cutset in G having all edges of maximum weight.
B) There exists a cycle in G having all edges of maximum weight.
C) Edge e cannot be contained in a cycle.
D) All edges in G have the same weight.
Answer : (C)

4 A software organization has been assessed at SEI CMM Level 4. Which of the following does the organization need to practice beside Process Change Management and Technology Change Management in order to achieve Level 5 ?
A) Defect Detection
B) Defect Prevention
C) Defect Isolation
D) Defect Propagation
Answer : (B)
5 Suppose that two parties A and B wish to setup a common secret key (D-H key) between themselves using the Diffle-Hellman key exchange technique. They agree on 7 as the modulus and 3 as the primitive root. Party A chooses 2 and party B chooses 5 as their respective secrets. Their D-H key is
A) 3
B) 4
C) 5
D) 6
Answer : (C)

6 Consider the following message M = 1010001101. The cyclic redundancy check (CRC) for this message using the divisor polynomial x5 + x4 + x2 + 1 is :
A) 01110
B) 01011
C) 10101
D) 10110
Answer : (C)

7 Which of the following statements is FALSE regarding a bridge
A) Bridge is a layer 2 device
B) Bridge reduces collision domain
C) Bridge is used to connect two or more LAN segments
D) Bridge reduces broadcast domain
Answer : (D)

8 What is the availability of a software with the following reliability figures?
Mean Time Between Failure (MTBF) = 25 days
Mean Time To Repair (MTTR) = 6 hours
A) 1%
B) 24%
C) 99%
D) 99.009%
Answer : (B)

9 A channel has a bit rate of 4 kbps and one-way propagation delay of 20 ms. The channel uses stop and wait protocol. The transmission time of the acknowledgement frame is negligible. To get a channel efficiency of at least 50%, the minimum frame size should be
A) 80 bytes
B) 80 bits
C) 160 bytes
D) 160 bits
Answer : (D)

10 In a depth-first traversal of a graph G with n vertices, k edges are marked as tree edges. The number of connected components in G is
A) k
B) k+1
C) n-k-l
D) n-k
Answer : (C)

11 Which of the following statements is TRUE about CSMA/CD
A) IEEE 802.11 wireless LAN runs CSMA/CD protocol
B) Ethernet is not based on CSMA/CD protocol
C) CSMA/CD is not suitable for a high propagation delay network like satellite network
D) There is no contention in a CSMA/CD network
Answer : (C)

12 Which one of the following regular expressions is NOT equivalent to the regular expression (a + b + c)* ?
A) (a* + b* + c*)*
B) (a*b*c*)*
C) ((ab)* + c*)*
D) (a*b* + c*)*
Answer : (C)

13 In a population of N families, 50% of the families have three children, 30% of the families have two children and the remaining families have one child. What is the probability that a randomly picked child belongs to a family with two children?
A) 3/23
B) 6/23
C) 3/10
D) 3/5
Answer : (B)

14 Which one of the following is NOT shared by the threads of the same process ?
A) Stack
B) Address Space
C) File Descriptor Table
D) Message Queue
Answer : (A)

15 A subnet has been assigned a subnet mask of 255.255.255.192. What is the maximum number of hosts that can belong to this subnet?
A) 14.
B) 30
C) 62
D) 126
Answer : (C)

16 A software organization has been assessed at SEI CMM Level 4. Which of the following does the organization need to practice beside Process Change Management and Technology Change Management in order to achieve Level 5 ?
A) Defect Detection
B) Defect Prevention
C) Defect Isolation
D) Defect Propagation
Answer : (B)

17 Suppose that two parties A and B wish to setup a common secret key (D-H key) between themselves using the Diffle-Hellman key exchange technique. They agree on 7 as the modulus and 3 as the primitive root. Party A chooses 2 and party B chooses 5 as their respective secrets. Their D-H key is
A) 3
B) 4
C) 5
D) 6
Answer : (C)

18 We have two designs D1 and D2 for a synchronous pipeline processor. D1 has 5 pipeline stages with execution times of 3 nsec, 2 nsec, 4 nsec, 2 nsec and 3 nsec while the design D2 has 8 pipeline stages each with 2 nsec execution time. How much time can be saved using design D2 over design D1 for executing 100 instructions?
A) 214 nsec
B) 202 nsec
C) 86 nsec
D) -200 nsec
Answer : (A)

19 Which of the following statements is FALSE regarding a bridge
A) Bridge is a layer 2 device
B) Bridge reduces collision domain
C) Bridge is used to connect two or more LAN segments
D) Bridge reduces broadcast domain
Answer : (D)

20 What is the availability of a software with the following reliability figures?
Mean Time Between Failure (MTBF) = 25 days
Mean Time To Repair (MTTR) = 6 hours
A) 1%
B) 24%
C) 99%
D) 99.009%
Answer : (B)

21 In a particular Unix OS, each data block is of size 1024 bytes, each node has 10 direct data block addresses and three additional addresses: one for single indirect block, one for double indirect block and one for triple indirect block. Also, each block can contain addresses for 128 blocks. Which one of the following is approximately the maximum size of a file in the file system?
A) 512 MB
B) 2 GB
C) 8 GB
D) 16 GB
Answer : (D)

22 On a TCP connection, current congestion window size is Congestion Window = 4 KB. The window size advertised by the receiver is Advertise Window = 6 KB. The last byte sent by the sender is LastByteSent = 10240 and the last byte acknowledged by the receiver is LastByteAcked = 8192. The current window size at the sender is
A) 2048 bytes
B) 4096 bytes
C) 6144 bytes
D) 8192 bytes
Answer : (B)

23 Which of the following statements is TRUE about CSMA/CD
A) IEEE 802.11 wireless LAN runs CSMA/CD protocol
B) Ethernet is not based on CSMA/CD protocol
C) CSMA/CD is not suitable for a high propagation delay network like satellite network
D) There is no contention in a CSMA/CD network
Answer : (C)

24 How many pulses are needed to change the contents of a 8-bit upcounter from 10101100 to 00100111 (rightmost bit is the LSB)?
A) 134
B) 133
C) 124
D) 123
Answer : (B)