CSS Computer Science 2010

Q.2.

(a) List OSI Seven Layers in order and briefly describe functions of each layer (10+6+4)

(b) What is difference between IPv4 and IPv6. Why IPv6 was developed when there

IPv4 was already available and implemented?

(c) What is difference between physical address, logical address, domain and port number?

Q.3.

Consider the following set of processes, with the length of the CPU-burst time given in milliseconds: (8+4+4+4)

Process Burst Time Priority

P1          10          3

P2           1           1

P3         2            3

P4         1            4

P5         5            2

The processes are assumed to have arrived in the order P1, P2, P3, P4, P5, all at time 0.

(a) Draw four Gantt charts illustrating the execution of these processes using FCFS, SJF, nonpreemptive priority (a smaller priority number implies a higher priority), and RR (quantum = 1) scheduling.

(b) What is the turnaround time of each process for each of the scheduling algorithms in part a?

(c) What is the waiting time of each process for each of the scheduling algorithms in part a?

(d) Which of the schedules in part a results in the minimal average waiting time (over all processes)?

Q.4.

(a) Consider a logical address space of eight pages of 1024 words each, mapped onto a physical memory of 32 frames. (6+10+4)

(i) How many bits are there in the logical address?

(ii) How many bits are there in the physical address?

(b) Consider the following segment table:

Segment Base Length

0 219 600

1 2300 14

2 90 100

3 1327 580

4 1952 96

What are the physical addresses for the following logical addresses?

(i) 0,430

(ii) 1,10

(iii) 2,500

(iv) 3,400

(v) 4,112

(c) What are the four necessary conditions for deadlock? Define each condition.

Q.5.

(a) Define following terms: (16+4)

(i) Class

(ii) Encapsulation

(iii) Abstraction

(v) Inheritance

(vi) Polymorphism

(vii) Copy Constructor

(viii) Serialization

(b) Write the output of the following program:

class Crectangle

{

private:

int width, height;

public:

CRectangle (int, int);

~CRectangle ();

int area (void)

{

return (width *height);

}

};

CRectangle::CRectangle (int a, int b)

{

width = a;

height = b;

}

void main ()

{

CRectangle recta (3,4), rectb (5,6);

cout<<"recta area = " << rect.area() << endl;

cout<<"rectb area = "<< rectb.area()<< endl;

}

Q.6.

(a) Suppose the following sorted array A of integers: (6+7+7)

A [0] A [1] A [2] A [3] A [4] A [5] A [6]

1 2 5 7 9 11 13

If you perform the binary search, for each of the search keys given below, write down the sequence of array values that are compared with the search value during the search. Searching for 2 Searching for 13 Searching for 8

(b) Trace the execution of SELECTION SORT on the following array by showing the contents of the array after every step.

A [0] A [1] A [2] A [3]

20 18 10 15

(c) If we implement the binary search tree with an array A, what will be the status of the array A after inserting the values {7, 4, 1, 3, 11} to an initially empty tree?

Q.7.

(a) Why normalization is used in relational databases? Define second and third normal form with an example. (10+3+3+4)

(b) What is difference between primary key and the alternate key? Why primary key is used in each relation?

(c) What is difference between weak entity and strong entity?

(d) Draw an entity relationship diagram between EMPLOYEES, DEPARTMENTS and PROJECTS assuming that each project can be started by only one department and each employee can be employed by only one department at a time. Write down any other assumption if you use it.

Q.8.

(a) Given a point P (10, 10). Rotate this point around origin O (0, 0) at an angle of 90 degree anticlockwise and calculate the resulting point (8+8+4)

(b) Write down the conditions for point clipping

(c) What are the major components of a Cathode Ray Tube (CRT). Write down names only.