Dec 2009 Paper II Part 2

Introduction

UGC NET Exam is a very popular exam in India for people interested in research. Previous Year Questions are an excellent option to learn about the exam pattern. By solving the PYQs, you will get a basic idea about your preparation. 

You can evaluate your weak areas and work on them to perform better in the examination. In this article, we have given the questions of UGC NET 2009 Dec Paper II. We have also explained every problem adequately to help you learn better.

Refer Dec 2009 Paper II Part 1 here.

Dec 2009 Paper II Part 2

26. Device on one network can communicate with devices on another network via a

(A) Hub/Switch

(B) Utility server

(C) File server

(D) Gateway

Answer: B

Devices on one network can communicate with devices on another network via a Utility server

The network may also include a node external to the subnetwork, e.g., a utility server. A system server of the customer periodically connects to a utility server of the utility company using a standard computer protocol, such as Hypertext Transfer Protocol (HTTP).

Unlike less advanced network hubs, a network switch forwards data only to one or multiple devices that need to receive it, rather than broadcasting the same data out of each of its ports. It works on OSI layer 2. Bridge: a device that connects multiple network segments. It works on OSI layers 1 and 2.

Utility computing, or The Computer Utility, is a service provisioning model in which a service provider makes computing resources and infrastructure management available to the customer as needed, and charges them for specific usage rather than a flat rate.

RJ-11 connectors are used to connect phone wires. BNC connectors are associated with thin coaxial cabling. ST connectors are associated with fiber-optic cabling. Answer: B. An AUI port is typically used to connect an external transceiver to a device such as a router.

 

27. What is the maximum window size in the sliding window protocol used in a computer network?

(A) 4

(B) 8

(C) 15

(D) 16

Answer: A

In Stop and Wait we have receiver and sender each of size one.

In Go Back N we can have Sender size as N-1 but receiver as only 1.

In Selective Repeat, we have a Sender and Receiver each of equal size. (N/2, N/2)

Now in question, it is given a 4-bit sequence, so we can have 16 sequence numbers in total and the maximum size is only possible with GBN.

so (2^n - 1)

 

28. Which of the following are Data Link Layer standards?

1. Ethernet

2. HSSI

3. Frame Relay

4. 10 – Base T

5. Token Ring

(A) 1, 2, 3          

(B) 1, 3, 5

(C) 1, 3, 4, 5     

(D) 1, 2, 3, 4, 5

Answer: C

Ethernet, frame relay, 10-Base T, and token ring are the basic data link layer standards.

 

29. In the case of Bus/Tree topology signal balancing issue is overcome by

(A) Modulation

(B) Polling

(C) Segmentation

(D) Strong transmitter

Answer: C

Signal balancing is needed to limit the signal over a certain limit; not too weak to attenuate across the medium before reaching far stations and not too strong to cause distortion, in both cases cannot be recovered.

This can be done within a certain limit and also this limits the bus length. To increase the length of the LAN, the bus is split into segments joined by repeaters(transparent devices); to overcome the effects of the impairment; in a non-closed way.

 

30. Match the following :

List-I

(i) Ethernet

(ii) Token Ring

(iii) Cut-through switch

(iv) Spanning tree

List-I

(a) Deterministic

(b) Utilize the full wire speed

(c) Prevent looping

(d) Checking valid address

Codes:

(A) i – d, ii – a, iii – b, iv – c

(B) i – a, ii – d, iii – b, iv – c

(C) i – d, ii – d, iii – c, iv – b

(D) i – d, ii – c, iii – b, iv – a

Answer: A

Ethernet = Checking valid address Codes

Token Ring = Deterministic

Token Ring access is more deterministic, compared to Ethernet’s contention-based CSMA/CD

Both Token Ring and ARCNET are deterministic and Ethernet is non-deterministic.

Cut-through switch = Utilize the full wire speed

A switch is said to work at “wire speed” if it has enough processing power to handle full Ethernet speed at minimum packet

sizes.

Most switches on the market are well ahead of network traffic capabilities supporting the full “wire speed” of Ethernet, 14,480

pps (packets per second), and Fast Ethernet, 148,800 pps.

Spanning Tree = Prevent looping

The Spanning Tree protocol is a networking standard, as defined by the IEEE in the 802.1d standard.

The purpose of Spanning Tree is to prevent loops in the LAN and to select the fastest network links,
 

31. In an absolute loading scheme which loader function is accomplished by the assembler?

(A) re-allocation

(B) allocation

(C) linking

(D) loading

Answer: A

Reallocation is accomplished by assembler.

 

32. Which of the following grammar is LR (1)?

(A) A®aAb, A®bAb, A®a , A®b

(B) A®aAa, A®aAb, A®c

(C) A®A+A, A®a

(D) Both (A) and (B)

Answer: D

Eplison can not be a look ahead symbole in LR(1).

Because whenever epsilon occoured it points next symbole.

 

33. A shift-reduce parser carries out the actions specified within braces immediately after reducing with the corresponding rule of the grammar.

S®xxW[print“1”]

S®y[print“2”]

W®S2[print“3”], what is the translation of “x x x x y z z”?

(A) 1 1 2 3 1

(B) 1 1 2 3 3

(C) 2 3 1 3 1

(D) 2 3 3 2 1

Answer: C

Making a tree and performing post-order traversal will yield an answer as A.

• S→xxW(print “1”)
• S→xxW(print “1”)
• W→Sz(print “3”)
• W→Sz(print “3”)
• S→xxW(print “1”)
• S→xxW(print “1”)
• W→Sz(print “3”)
• W→Sz(print “3”)
• S→y(print “2”)

 

34. Context-free Grammar (CFG) can be recognized by

(A) Finite state automata

(B) 2-way linear bounded automata

(C) push down automata

(D) both (B) and (C)

Answer: D

Context-free Grammar (CFG) can be recognized by both 2-way linear bounded automata and push down automata . 

regular --> dcfl --> ncfl --> Csl --> recursive -->recursive enumerable (implication)

 

35. Synthesized attributes can be easily simulated by a

(A) LL grammar

(B) Ambiguous grammar

(C) LR grammar

(D) None of the above

Answer: C

Synthesized attributes can be easily simulated by a LR grammar bcz synthesized attributes evaluates in bottom up fashion and LR grammar also evaluates in  bottom up fashion.

 

36. In the process management Round-robin method is essentially the pre-emptive version of …………

(A) FILO

(B) FIFO

(C) SSF

(D) Longest time first

Answer: B

In Round robbbin , a queue is maintained which stores the input as it comes in FIFO order

Its different from FIFO because of pre emption  

When does premption occur

a time quantum is allocated( a specific time say 10 sec for a process, then even if the process is not completed, the next process in queue enters for execution and the remainingg of this executed process is also added in the queue

so the process enters in FIFO with premption

ANSWER = FIFO

 

37. A page fault

(A) is an error specific page.

(B) is an access to the page not currently in memory.

(C) occur when a page program occur in a page memory.

(D) page used in the previous page reference.

Answer: B

A page fault (sometimes called #PF, PF or hard fault) is a type of exception raised by computer hardware when a running program accesses a memory page that is not currently mapped by the memory management unit (MMU) into the virtual address space of a process.
 

38. A semaphore count of negative n means (s=–n) that the queue contains ………….. waiting processes.

(A) n + 1

(B) n

(C) n – 1

(D) 0

Answer: B

Semaphore count of negative n means that the queue contains n waiting processes

and nonnegative count means that the queue of waiting processes is empty .
 

39. A program is located in the smallest available hole in the memory is ……………

(A) best – fit

(B) first – bit

(C) worst – fit

(D) buddy

Answer: A

Best Fit

The best fit deals with allocating the smallest free partition which meets the requirement of the requesting process. This algorithm first searches the entire list of free partitions and considers the smallest hole that is adequate. It then tries to find a hole which is close to actual process size needed.

Advantage

Memory utilization is much better than first fit as it searches the smallest free partition first available.

Disadvantage

It is slower and may even tend to fill up memory with tiny useless holes.

 

40. The Unix command used to find out the number of characters in a file is

(A) nc

(B) wc

(C) chcnt

(D) lc

Answer: B

The wc (word count) command in Unix/Linux operating systems is used to find out number of newline count, word count, byte and characters count in a files specified by the file arguments. The syntax of wc command as shown below.

# wc [options] filenames
 

41. Software Engineering is a discipline that integrates ………….. for the development of computer software.

(A) Process

(B) Methods

(C) Tools

(D) All

Answer: D

All the options are relevant.
 

42. Any error whose cause cannot be identified anywhere within the software system is called …………..

(A) Internal error

(B) External error

(C) Inherent error

(D) Logic error

Answer: B

Any error whose cause cannot be identified anywhere within the software system is called external error.
 

43. Recorded software attributes can be used in the following endeavours :

(i) Cost and schedule estimates.

(ii) Software product reliability predictions.

(iii) Managing the development process.

(iv) No where

Codes:

(A) (i) (ii) (iv)

(B) (ii) (iii) (iv)

(C) (i) (ii) (iii)

(D) (i) (ii) (iii) (iv)

Answer: C

Recorded software attributes are those attributes that are already in use for some software.

With the requirements being similar for 2 softwares, these attributes may be used again.

There may be some attributes in the following endeavours which are similar:

Cost and schedule estimates, Software product reliability predictions, Managing the development process.

 

44. Black Box testing is done

(A) to show that s/w is operational at its interfaces i.e. input and output.

(B) to examine internal details of code.

(C) at the client side.

(D) none of the above.

Answer: A

Black Box Testing, also known as Behavioral Testing, is a software testing method in which the internal structure/ design/ implementation of the item being tested is not known to the tester. These tests can be functional or non-functional, though usually functional.
 

45. The name of the transaction file shall be provided by the operator and the file that contains the edited transactions ready for execution shall be called

(A) Batch. Exe

(B) Trans. Exe

(C) Opt. Exe

(D) Edit.Exe

Answer: C

Transactions has to be managed by the executable files.

 

46. The single-stage network is also called

(A) one-sided network

(B) two-sided network

(C) recirculating network

(D) pipeline network

Answer: C

Single-stage networks A single-stage network is a switching network with N input selectors (IS) and N output selectors • The single-stage network is also called a recirculating network. Data items may have to recirculate through the single stage several times before reaching their final destinations.

 

47. Analysis of a large database to retrieve information is called

(A) OLTP

(B) OLAP

(C) OLDP

(D) OLPP

Answer: B

OLAP (online analytical processing) is computer processing that enables a user to easily and selectively extract and view data from different points of view.

 

48. Which technology is sometimes referred to as wireless cable?

(A) MMDS

(B) ATM

(C) LMDS

(D) CDMA

Answer: A

Advanced Wireless Services (AWS) is a wireless telecommunications spectrum band used for mobile voice and data services, video, and messaging. AWS is used in the United States, Argentina, Canada, Colombia, Mexico, Chile, Paraguay, Peru, Ecuador and Uruguay. It replaces some of the spectrum formerly allocated to Multipoint Multichannel Distribution Service (MMDS), sometimes referred to as Wireless Cable, that existed from 2150 to 2162 MHz.

 

49. Another name for IEEE 802.11 a is …………………

(A) Wi-Max

(B) Fast Ethernet

(C) Wi-Fi

(D) 802.11 g

Answer: C

Wi-FI is another name for IEEE 802.11 a.

 

50. The unlicensed National Information Infrastructure band operates at the …………. frequency

(A) 2.4 GHz

(B) 5 GHz

(C) 33 MHz

(D) 5 MHz

Answer: B

The unlicensed National Information Infrastructure band operates at the 5GHz.