IPE MARCH 2015
OOPS & JAVA
1. What IS Java byte code?
A) Java Bytecode: Java bytecode is the form of instructions that the Java virtual machine
executes. Each bytecode opcode is one byte in length, although some require parameters,
resulting in some multi-byte instructions.
2. What is a class?
A) Class: A class is a collection of objects of similar type. It is a template from which objects
are created.
3. What is an array?
A) Array: An array is a collection of similar type of data elements which are stored in
consecutive memory locations under a common variable name.
4. What is Inheritance?
A) Inheritance: Inheritance is the process by which objects of one class acquire the properties of
objects of another class. Inheritance supports the concept of hierarchical classification.
Inheritance provides the idea of reusability.
5. Write any four Java API Packages?
A)
Package
java.lang
java.util
java.applet
java.awt
java.io
Purpose
It includes classes for primitive types, strings, math functions, threads and
exceptions.
Language utility classes such as vectors, hash tables, random numbers, date etc.,
Classes for creating and implementing applets.
Includes classes for windows, buttons, list, menus and so on.
Input or output support classes.
6. What is logical error?
A) Logical Errors: The programmer might be using a wrong formula or the design of the
program itself is wrong. Logical errors are not detected either by Java compiler or JVM.
The programmer solely responsible for them.
7. What is Multitasking?
A) Multitasking: It is an operating system concept in which multiple tasks are performed
simultaneously.
8. What are the methods of applet class?
A)
A)
B)
C)
D)
E)
init
start
stop
destroy
paint
9. What is AWT?
A) AWT: AWT stands for Abstract Window Tool Kit. It is a portable GUI library among
various operating systems for stand-alone applications.
10. What are the classes involved in event handling?
A) Event handling involves four types of classes
1. Event Sources
2. Event classes
3. Event Listeners
4. Event Adapters
11. Write about main features of Java.
A) Features of Java:
1. Object Oriented: In java everything is an Object. Java can be easily extended since it is
based on the Object Model.
2. Platform Independent: Platform means an operating system such as windows, Unix,
linux,etc., If a java program is compiled, it is compiled into platform independent byte code.
This byte code can run on any platform. Hence we can say that the java is platform independent.
3. Simple: Java is designed to be easy to learn. If we understand the basic concept of OOP java
would be easy to master.
4. Secure: With java’s secure feature it enables to develop virus – free, tamper – free systems.
Authentication techniques are based on public – key encryption.
5. Architetural – Neutral: Java compiler generates an architecture – neutral object file format
which makes the compiled code to be executable on many processors with the presence Java
runtime system.
6. Portable: We may carry the java byte code to any platform.
7. Robust: Java makes an effort to eliminate error prone situations by emphasizing mainly on
compile time error checking and runtime checking.
8. Multi – threaded: With java’s multi-threaded feature it is possible to write programs that can
do many tasks simultaneously. This design feature allows developers to construct smoothly
running interactive applications.
9.. Interpreted: Java byte code is translated on the fly to native machine instructions and is not
stored any where. The development process is more rapid and analytical since the linking is an
incremental and light weigh process.
10. High Performance: With the use of Just – In – Time compilers Java enables high
performance.
11. Distributed: Java is designed for the distributed environment of the internet.
12. Dynamic: Java programs can carry extensive amount of run-time information that can be
used to verify and resolve accesses to objects on run – time.
12. Write about various operators in Java.
A) Arithmetic Operators: Arithmetic Operators are used to perform arithmetic operations on two
operands.
Ex: a and b are integer variables and assigned a=5 and b=3 then
Operator
Purpose
Arithmetic
Result
Expression
+
Addition
a+b
8
Subtraction
a-b
2
*
Multiplication
a*b
15
/
Division
a/b
1
%
Remainder after
a%b
2
integer division
Relational Operators: Relational Operators: There are six relational operators supported by Java
language. These returns result in the form of ‘true’ or ‘false’.
Ex: a, b and c are integer variables and assigned 3, 5 and 10 respectively.
Operator
Purpose
Relational
Expression
Result
==
is Equal to
c = = 10
False
!=
is Not equal to
a != b
True
>
is Greater than
a>b
False
<
is Less than
(a+b)<c
True
>=
is Greater than or equal
to
a>=3
True
<=
is Less than or equal to
b<=a
False
13. Explain different data types in java.
A). Java has four main primitive data types built into the language. We can also create our own
data types.
Integer: byte, short, int, and long.
Floating Point: float and double
Character: char
Boolean: variable with a value of true or false.
The following chart summarizes the default values for the java built in data types.
Type
Size in Bytes
Range
byte
1 byte
-128 to 127
short
2 bytes
-32,768 to 32,767
int
4 bytes
-2,147,483,648 to 2,147,483,
647
8 bytes
-9,223,372,036,854,775,808
to
9,223,372,036,854,775,807
float
4 bytes
approximately
±3.40282347E+38F
(6-7 significant decimal digits)
Java implements IEEE 754
standard
double
8 bytes
approximately
±1.79769313486231570E+308
(15 significant decimal digits)
char
2 byte
0 to 65,536 (unsigned)
boolean
not precisely defined*
true or false
Data Type
Default Value (for fields)
Range
Byte
0
-127 to +128
long
14. Discuss briefly about decision – making statements in Java.
A) if statement: if statement is used to control the flow of execution of statements.
Syntax: if (test expression)
{
Statement _block;
}
statement x;
The statement _block may be a single statement or multiple statements. If the test
expression is ‘true’, the statement_block will be executed, otherwise the statement block will be
skipped and the control flows to the immediately following the statement block.
Ex: if (a>b) big = a;
if …… else statement: The if…..else statement is an extension of the simple if statement. If
the test expression is true then statements under if will be executed else statements under else
will be executed.
Syntax: if (test expression)
{
true block statements;
}
else
{
false block statements;
}
Ex: if (a>b) big = a; else big = b;
Switch Statement: The switch statement tests the value of a given variable against a list of value
and when a match is found, corresponding block of statements associated with the case will be
executed. If none is matched ‘default’ block will be executed. The ‘break’ statement at the end of
each block signals the end of a particular case causes an exit from the switch statement,
transferring the control to the statement immediately following the switch.
Syntax:
switch(expression)
{
case value: block1;
break;
case value: block2;
break;
case value: block3;
break;
---------------------------------------
default:
default block;
break;
}
15. Write a program to find factorial of a given number.
A) //to find the factorial by using while loop
import java.util.Scanner;
class Factoria{
public static void main(String args[]){
int i,f=1,n;
System.out.println("Enter an Integer:");
Scanner in = new Scanner(System.in);
n = in.nextInt();
i = 1;
while(i<=n){
f*=i;
++i;
}
System.out.println("Factorial of"+n+"is" +f);
}}
Output:
Enter an Integer:
5
Factorial of 5 is 120
16. Explain the polymorphism with an example.
A) Polymorphism: Polymorphism means the ability to take more than one form is called
Polymorphism.
We can store all the objects of extended classes in to variable of parent class. The only possible
way to access an object is through a reference variable. A reference variable can be only one
type. Once declared the type of reference variable cannot be changed.
The reference variable can be reassigned to other objects provided that it is not declared final.
The type of the reference variable would determine the methods that it can invoke on the object.
A reference variable can refer to any object of its declared type or any subtype of its declared
type. A reference variable can be declared as a class or interface type.
Ex: class Box{
int w,h;
void info( ){
System.out.println("This is a simple box");
System.out.println("width = "+w+"height="+h);
}}
class woodenBox extends Box{
int life;
void info( ){
System.out.println("This is a wooden box");
}}
class SteelBox extends Box{
int wg;
void info( ){
System.out.println("This is a steel box");
}}
class LargewoodenBox extends woodenBox{
void info( ){
System.out.println("This is a Huge wooden Box");
}}
class BoxDemo{
public static void main(String ary[ ]){
Box x;
Box b1= new Box( );
woodenBox wb=new woodenBox( );
SteelBox s1=new SteelBox( );
LargewoodenBox p1=new LargewoodenBox( );
b1.info( );
wb.info( );
s1.info( );
p1.info( );
}}
Output:
This is a simplebox
Width=0 hieght=0
This is a wooden box
This is a steel box
This is a Huge wooden Box
17. Discuss briefly about Packages and Interfaces.
A) Interfaces Vs Packages
A package is just a mechanism for grouping objects, it is very similar to grouping items
within a folder or directory on a file system. A class is found with in a package, but this does not
have an impact on the class behavior.
An Interface, however, is a.java file that is used (implemented) by another class to tell
the outside world that it conforms to a certain specification.
Interfaces have more in common with abstract classes than they do with packages. An
Interface, by definition, cannot have any implemented methods.
An abstract class can define some methods and leave some methods to implemented by a
subclass.
A class can implement many interfaces, but can only extend one (abstract) class.
18. Write about methods of Applet Class.
A) Methods Of Applet Class (Life Cycle of an applet): Four methods give us the framework
on which we build an applet.
1. init : This method is intended for whatever initialization is needed for our applet. It is
called after the param tags inside the applet tag have been processed.
2. Start: This method is automatically called after the browser calls the init method. It is
also called whenever the user returns to the page containing the applet after having gone
off to other pages.
3. Stop: This method is automatically called when the user moves off the page on which the
applet sits. It can, therefore, be called repeatedly in the same applet.
4. Destroy: This method is only called when the browser shuts down normally
5. Paint: Invoked immediately after the start() method and also any time the applet needs to
repaint itself in the browser. The paint() method is actually inherited from the java awt.
RDBMS
1. What is DBMS?
A) A database management system (DBMS) can be defined as a collection of software packages
for processing the database.
2. What is a Domain?
A) Domain: Domain is a pool of values of a specific attribute. Separate domains for separate
attributes.
3. What is Tuple?
A. Tuple is a row(record) of a table .
4. What are the Formal Query Languages?
A. Formal Query Languages are formal in the sense that they are lack of ‘syntactic behavior ‘of
commercial query languages.
Some of the formal Query Languages are listed below:
- The Relational Algebra
- Tuple Relational Calculus
- Domain Relational Calculus
5. What is Degree of Table in Relational Model?
A) Number of attributes is called degree.
6. Write the Internal Datatypes in SQL.
A) varchar , varchar2 , numb, long, date ,etc
7. What is Sub – query?
A. Nesting of queries, one within another, is termed as subquery.
8. Wha is a Database Trigger?
A) Database Trigger: A database trigger is a stored procedure that will be executed when an
event is occurred i.e., insert, update, delete statement is issued against the associated table.
9. Define system and Sub-system.
A. System: System is an orderly grouping of interdependent components linked together to
approach a Specific object or goal. Ex: Railway reservation system , Net banking system.
Sub System: One of the number of component parts of a system. All the subsystems must
function together in an integrated manner for the system to operate as designed.
10. Define Data Dictionary?
A. Data Dictionary: Data Dictionary is a repository that contains descriptions of all data objects
produced by the software.
11. Explain different Data Models.
A. Different data models are
1. Object based data models
2. Record – based data models
3. Physical data models
1. Object base data models: Object-based logical models are used in describing data at
logical and view levels. They are characterized by the fact they provide flexible structuring
capabilities and allow data constraints to be specified explicitly. There are many different
data models, some of them are
i. The Entity-relationship model
ii. The Object-oriented model
iii. The semantic data model
iv. The Functional data model
2. Record based data models:
In Record based data models; the database is structured in
fixed formats records of several types. Each record defines fixed number of fields (attributes)
and each field is fixed length. These models are used to specify the overall logical structure of
the database and are used in describing the database at conceptual level.
The three widely accepted record – based data models are:
a) Relational model
b) Network model
c) Hierarchical model
3. Physical data models: Physical data model are used to describe data at the lowest level.
In contrast to logical data models, there are few number of physical data models which are
in use. Very few physical data models have been proposed so far. Two of these well known
models are the unifying model and the frame memory model.
12. What are the functions of DBA? Explain.
A)
1. Schema definition
2. Storage structure and Access method definition
3. Schema physical organization and modification
4. Granting of authorization for data access
5. Routine maintenance
1. Schema Definition: The DBA creates the original database schema by executing a set of
definition statements in the DDL.
2. Storage structure and Access method definition: DBA will decide the actual storage
structure and different access methodologies for the database.
3. Schema physical organization and modification: The DBA carries out the changes to the
schema and physical organization to reflect the changing needs of the organization or to alter the
physical organization to improve the performance.
4. Granting of authorization for data access: By granting different types of authorization, the
database administrator can regulate which of the database various can access.
5. Routine maintenance: DBA is the final authority to regulate daily activities.
13. Explain mapping constraints with diagram.
A) There are 4 types of mapping constraints.
1. ONE – to – ONE relationship
2. MANY – to – ONE relationship
3. ONE – to – MANY relationship
4. MANY – to – MANY relationship
1. ONE – to – ONE relationship: An entity in A is associated with at most one entity in B ,
An entity in B is also associated with at most one entity in A.
Example : Relationship between the entities principal and college. i.e., Principals can lead a
single college and a principal can have only one college
2. Many – to – One relationship: An entity set in A is associated with at most one entity in B,
An entity in B however can be associated with any number of entities in A.
Example: Relationship between the entities Districts and state .i.e. many districts belong to a
single state but many states cannot belong to single district.
3. ONE – to - MANY relationship: An entity set A is associated with any number of entities in
B. An entity in B, however can be associated with at most one entity in A.
Example: Relationship between the entities class and student i.e., a class can have many students
but a student cannot be in more than one class at a time.
4. MANY – to – MANY relationship: An entity set A is associated with any number of
entities in B and an entity set in B is associated with any number of entities in A.
Example: Relationship between the Entities College and course .i.e. a college can have many
courses and course can be offered by many colleges.
14. What is Key? Write about different types of Keys.
A) Key: A key allows us to identify a set of attributes in an entity . Keys also help uniquely
identify relationships, and thus distinguish relationships from each other.
The keys can be categorized in to
1. Super Key: A Super key is a set of one or more attributes that, taken collectively; allow us to
identify uniquely an entity in the entity set. For example, the ‘student_id’ attribute of the entity
set student is sufficient to distinguish one student entity from another. Thus, ‘student_id’ is a
super key
2. Candidate Key: A super key with minimal values is called a candidate key. A super key that
does not contain a subset of attributes, that is itself super key.
3. Primary key: The Primary key of a relational data base table is a column name which
uniquely identifies each record in the table. It cannot contain NULL entries.
4. Secondary key :- An attribute ( or ) Combination of attributes used strictly for data retrieval
purposes.
5. Foreign key :- An attribute or Combination of attributes in one table whose values must
either match the primary key in another table or be NULL.
15. What are CODD rules in Relational Model.
A) CODD rules
Edgar F. Codd, proposed thirteen rules (numbered zero to twelve) and said that if a
Database Management System meets these rules, it can be called as a Relational Database
Management System. These rules are called as Codd’s12 rules. Hardly any commercial product
follows all.
0. Foundation Rule
A RDBMS must manage its stored data using only its relational capabilities.
1. Information Rule
All information in the database should be represented in one and only one way - as values
in a table.
2. Guaranteed Access Rule
Each and every datum (atomic value) is guaranteed to be logically accessible by resorting
to a combination of table name, primary key value and column name.
3. Systematic Treatment of Null Values
Null values (distinct from empty character string or a string of blank characters and
distinct from zero or any other number) are supported in the fully relational DBMS for
representing missing information in a systematic way, independent of data type.
4. Dynamic On-line Catalog Based on the Relational Model
The database description is represented at the logical level in the same way as ordinary
data, so authorized users can apply the same relational language to its interrogation as
they apply to regular data.
5. Comprehensive Data Sublanguage Rule
A relational system may support several languages and various modes of terminal use.
However, there must be at least one language whose statements are expressible, per some
well-defined syntax, as character strings and whose ability to support all of the following
is comprehensible:
a. data definition
b. view definition
c. data manipulation (interactive and by program)
d. integrity constraints
e. authorization
f. transaction boundaries (begin, commit, and rollback).
6. View Updating Rule
All views that are theoretically updateable are also updateable by the system.
7. High-level INSERT, UPDATE, and DELETE
The capability of handling a base relation or a derived relation as a single operand applies
nor only to the retrieval of data but also to the insertion, update, and deletion of data.
8. Physical Data Independence
Application programs and terminal activities remain logically unimpaired whenever any
changes are made in either storage representation or access methods.
9. Logical Data Independence
Application programs and terminal activities remain logically unimpaired when
information preserving changes of any kind that theoretically permit unimpairment are
made to the base tables.
10. Integrity Independence
Integrity constraints specific to a particular relational database must be definable in the
relational data sublanguage and storable in the catalog, not in the application programs.
11. Distribution Independence
The data manipulation sublanguage of a relational DBMS must enable application
programs and terminal activities to remain logically unimpaired whether and whenever
data are physically centralized or distributed.
12. Non - subversion Rule
If a relational system has or supports a low-level (single-record-at-a-time) language, that
low-level language cannot be used to subvert or bypass the integrity rules or constraints
expressed in the higher-level (multiple-records-at-a-time) relational language.
16. Explain DML Commands with example.
A.
DML Commands: insert , select , delete and update
1. insert: The INSERT INTO Statement is used to add new rows of data to a table in the
database.
Syntax:
Insert into <table name> values (value1 , value2 , value3 , ..valueN);
Example: Following statements would create three records in student table:
insert into student values(101 , ‘chanukya’);
insert into student values(102 , ‘kavya’);
insert into student values(101 , ‘satish’);
2.select: SELECT statement is used to fetch the data from a database table which returns
data in the form of result table. These result tables are called result-sets.
Syntax:
Select column1 , column2 , column from <table name>;
Here, column1, column2...are the fields of a table whose values you want to fetch.
If you want to fetch all the fields available in the field, then you can use the following
syntax:
Select * from <table_name>
Example1: select * from student;
Then the output will be
Stno
stname
-------
---------
101
chanukya
102
kavya
103
satish
Example2: select stname from student;
Stname
--------chanukya
kavya
satish
Example3: select * from student where stno >=102 ;
Then the output will be
Stno
stname
-------
---------
102
kavya
103
satish
3. update: The UPDATE command is used to modify the existing records in a table.
You can use WHERE clause with UPDATE query to update selected rows
otherwise all the rows would be affected.
Syntax:
UPDATE < table name > SET column1 = value1, column2 = value2...., columnN = valueN
WHERE [condition];
Example:
Consider the student table having the following records:
Sql>select * from student;
Stno
-------
stname
---------
101
chanukya
102
kavya
103
satish
sql> update student set stname = ‘ratnam’ where stno = 101;
Sql>select * from student;
then the output will be as follows
Stno
-------
stname
---------
101
ratnam
102
kavya
103
satish
4.delete: DELETE command is used to delete the existing records from a table.
You can use WHERE clause with DELETE query to delete selected rows,
otherwise all the records would be deleted.
Syntax:
Delete from <table name> where [condition] ;
Example:
Sql>select * from student;
then the output will be as follows
Stno
stname
-------
---------
101
ratnam
102
kavya
103
satish
Sql>delete from student where stno = 101;
Sql> select * from student;
The output will be as follows
Stno
stname
-------
---------
102
kavya
103
satish
17. Explain control structure in PL / SQL.
A) PL/SQL can process the data using flow of control statements. The flow of control can be
classified into three categories
 Conditional Controls
 Iterative Controls
 Sequential Controls
Conditional Controls: Conditional Statements are three types, those are
A. if statements
B. if then else statements
C. if then else if statements.
A) if statement: Sequence of statements can be executed based on some condition using the
if statement.
Syntax: if <condition> then
Statements;
end if;
B) if then else : Sequence of statements can be executed based on some condition using the
if statement. An else clause in the ‘if then else’ statement defines what is to be done if the
condition is false or null.
Syntax: if <condition> then
Statements;
else
Statement;
end if;
Iterative Controls: These statements are used to execute a particular statement for repeated
number of times.
A. Simple Loop
B. for Loop
C. while Loop
A) Simple Loop: Simple “loop” should be placed before the first statement in the sequence
and the keyword “end loop” after the last statement.
Syntax: loop
Statements;
end loop;
B) for Loop: The “for” loop will be executed for repeated number of times by automatically
declaring loop variable and also loop variable is always incremented by 1.
Syntax: for <variable> in [reverse] start …… end (star=lower bound, end= upper bound)
loop
Statements;
end loop;
C) while Loop: In while loop the keyword “loop” has to be placed before the first statement in
the sequence statements to be repeated, while the keyword “end loop” will be placed
immediately after the last statement.
Syntax: while<condition>
loop
Statements;
end loop;
Sequential Controls:
GOTO: GOTO statement change of the flow of control within PL/SQL block.
Syntax: GOTO<code_block_name>;
18. Explain different stages of System Development Life cycle (SDLC).
A. A) System Development Life Cycle :
The stages involved during System Development Life Cycle are ::
1. Recognition of need
2. Feasibility study
3. Analysis
4. Design
5.
Implementation
6. Post implementation and maintenance
1. Recognition of need: This gives a clearer picture of what actually the existing system is.
The preliminary investigation must define the scope of the project and the perceived
problems, opportunities and directives that triggered the project.
2. Feasibility Study: The goal of feasibility study is to evaluate alternative system and to
purpose the most feasible and desirable system for development. In the process of
feasibility study, the cost and benefits are estimated with greater accuracy. If cost and
benefit can be quantified, they are tangible ; if not , they are called intangible.
3. System Analysis: System analysis is an in-depth study of end user information needs
that produces
functional requirements that are used as the basis for the design of a new
information system.
4. System Design: System design can be viewed as the design of user interface, data,
process and
system specification .
5. System Implementation: Implementation is the stage where theory is converted into
practical. The implementation is a vital step in ensuring the success of new systems. Even
a well designed system can fail if it is not properly implemented.
6. Post Implementation and Maintenance: Once a system is fully implemented and being
operated
by end user, the maintenance function begins. Systems maintenance is the monitoring,
evaluating and modifying of operational information system to make desirable or necessary
improvements.
DCCN
1. What is data communication?
A) Data communication is the transmission of electronic data over some media. The media may
be cables, microwaves or fiber optics.
Types of data communications are
- Point to point communication
- Point to multipoint communication
2. List various types of Computer Networks.
A) Different types of computer networks
Depending upon the geographical area covered by a network, it is classified as:
– Local Area Network (LAN)
– Metropolitan Area Network (MAN)
– Wide Area Network (WAN)
– Personal Area Network (PAN)
3. Expand LAN, WAN, BBN, GAN.
A)
 LAN : Local Area Network
 WAN: Wide Area Network
 BBN: Back Bone Networks
 GAN: Global Area Networks
4. What is File Server?
A) File server – A file server is a computer attached to a network that has the primary purpose
for sharing of files (such as documents, sound files, photographs, movies, images, databases,
etc.) that can be accessed by the clients.
5. What is FTP?
A. File Transfer Protocol, or FTP, is a protocol used for transferring files from one computer to
another - typically from your computer to a web server.
6. What is Hacking?
A) Hacking: Hacking is an activity that is used by a hacker to steal the information from any of the
device or computer system. Also a hacker can use the system to work as a server to route the
information for the own purpose. Hackers can use the contact information of system and send spam
emails to that email ids.
7. Write any three advantages of HTML.
A) 1. First advantage it is widely used.
2. Every web browser supports HTML language.
3. Easy to learn and use.
4. It is by default in every windows so you don't need to purchase extra software.
8. What is Table Tag in HTML?
A) Table Tag
The <table> tag defines an HTML table. An HTML table consists of the <table> element and
one or more <tr>, <th>, and <td> elements. The <tr> element defines a table row, the <th>
element defines a table header, and the <td> element defines a table cell. The attributes used
in <table> tag are “align=left, center or right”, border and bgcolor. The attributes used in <tr>
tag are “align=left, center or right”, colspan and rowspan. For example, <td colspan=2> will
take up two columns and <td rowspan=2> will take up two rows.
9. Write advantages of DHTML?
A. Advantages:
 Dynamic content, which allows the user to dynamically change Web page content
 Dynamic positioning of Web page elements.
 Dynamic style, which allows the user to change the Web page’s color, font, size or
content.
10. What is DOM?
A) DOM: DOM is "a platform- and language-neutral interface that will allow programs and
scripts to dynamically access and update the content, structure, and style of documents. The
document can be further processed and the results of that processing can be incorporated
back into the presented stage.
11. Write about Transmission modes.
A) Types of Transmission Modes
There are three ways for transmitting data from one point to another
1. Simplex: 1. In simplex mode the communication can take place only in one direction. The
receiver receives the signal from the transmitting device. This mode of flow of information is
Unidirectional. Example: Radio, T.V., Pager transmission.
2. Half-duplex: In half-duplex mode the communication channel is used in both directions, but
only in one direction at a time. Thus a half-duplex line can alternately send and receive data.
Example is the wireless communication.
3. Full-duplex: In full duplex the communication channel is used in both directions at the same
time. Use of full-duplex line improves the efficiency as the line turn-around time required in
half-duplex arrangement is eliminated. Example of this mode of transmission is the telephone
line.
12. Explain different types Computer Networks.
A) Different types of computer networks
Depending upon the geographical area covered by a network, it is classified as:
– Local Area Network (LAN)
– Metropolitan Area Network (MAN)
– Wide Area Network (WAN)
– Personal Area Network (PAN)
LAN(Local Area Network):
A LAN is a network that is used for communicating among computer devices, usually within an office
building or home.
 Is limited in size, typically spanning a few hundred meters, and no more than a mile
• Is fast, with speeds from 10 Mbps to 10 Gbps
• Requires little wiring, typically a single cable connecting to each device
• Has lower cost compared to MAN’s or WAN’s
•
MAN(Metropolitan Area Network):
• A MAN is a large computer network that usually spans a city or a large campus.
• A MAN is optimized for a larger geographical area than a LAN, ranging from several blocks of
buildings to entire cities.
• A MAN might be owned and operated by a single organization, but it usually will be used
by many individuals and organizations.
• A MAN often acts as a high speed network to allow sharing of regional resources.
• A MAN typically covers an area of between 5 and 50 km diameter.
• Examples of MAN: Telephone company network that provides a high speed DSL to
customers and cable TV network.
WAN( Wide Area Network):
• WAN covers a large geographic area such as country, continent or even whole of the world.
• A WAN is two or more LANs connected together. To cover great distances, WANs may transmit
data over leased high-speed phone lines or wireless links such as satellites.
• Multiple LANs can be connected together using devices such as bridges, routers, or gateways, which
enable them to share data.
• The world's most popular WAN is the Internet.
PAN(Personal Area Network):
• A PAN is a network that is used for communicating among computers and computer devices (including
telephones) in close proximity of around a few meters within a room
• It can be used for communicating between the devices themselves, or for connecting to a larger
network such as the internet.
• PAN’s can be wired or wireless
• A personal area network (PAN) is a computer network used for communication among
computer devices, including telephones and personal digital assistants, in proximity to an
individual's body.
• The devices may or may not belong to the person in question. The reach of a PAN is
typically a few meters.
13. Explain any three Network topologies in detail.
Diagram
Kind of
Topology
Description, Advantages, and Disadvantages
Description:



Ring
Devices are connected from one to another to form a ring
shape.
Each host is connected to the next and the last node is
connected to the first.
A data token1 is used to grant permission for each computer
to communicate.
Advantages:


Easy to install and wire.
Because every computer is given equal access to the token,
no one computer can monopolize the network.
Disadvantages:



Requires more cable than a bus topology.
If one computer fails it can affect the whole network.
It is difficult to identify the problem if the entire network
shuts down.
Description:

All hosts are connected to the backbone cable in a
linear2 fashion.
Advantages:
Bus


Easy to connect a computer or peripheral.
Requires less cable length than a star topology.
Disadvantages:



If there is a break in the backbone cable, the entire network
shuts down.
Both ends of the backbone cable require terminators.
It is difficult to identify the problem if the entire network
shuts down.
Description:




All hosts are connected to a single point of concentration.
Usually uses a hub3 or switch4 as a center node.
Range limits are about 100 meters from the hub
Data on a star network passes through the hub or
concentrator before continuing to its destination.
Advantages:
Star




It is easy to modify and add new computers to a star
network without disturbing the rest of the network.
If one node or workstation (beside the middle node) goes
down, the rest of the network will still be functional.
The center of a star network is a good place to figure out
where the network faults are located.
You can use several cable types in the same network if the
hub you have can handle multiple cable types.
Disadvantages:


Requires more cable than a bus topology.
If the middle node goes down , then the entire network goes

down.
It is more expensive than because all cables must be
connected to one central point.
Description: One "root" node connects to other nodes, which in
turn connect to other nodes, forming a tree structure. Information
from the root node may have to pass through other nodes to reach
the end nodes.
Advantages:
• Point-to-point wiring for individual segments.
• Supported by several hardware and software vendors.
Tree
• All the computers have access to the larger and their immediate
networks.
Disadvantages:
• Overall length of each segment is limited by the type of cabling used.
• If the backbone line breaks, the entire segment goes down.
• More difficult to configure and wire than other topologies.
Description:

Each host is connected to all the other hosts.
Advantages:

Mesh

Increased reliability since there are multiple paths for each
node to take.
Increased speed since shortcuts have been created by add
more cables/links.
Disadvantages:

The cost of cabling all the hosts together is expensive and
time consuming.
14. Discuss about Routers and Gateways.
A. Router: A Router is a device that forwards data packets along networks. A router is
connected to at least two networks, commonly two LANs or WANs or a LAN and
its ISP's network. Router reduces network traffic by using routing table.
Gateway: A gateway is a network element that acts as an entrance point to another network.
For example an access gateway is a gateway between telephony network and other network
such as internet. LANs may have component called gateways, which assists in transferring
from one LAN to another LAN.
A gateway is generally a work station or server. It is a two-way path between networks. It is
used to connect different types of networks. Gateway is a work station by which we can
make our connection between external network and internal network. Gateway belongs to
transport layer and application layer of the OSI model.
Gateways also connect the two networks even if the protocols are different. So protocol
conversion is also done by gateways
15. Explain various Web browsers.
A) Web Browsers:
1. Internet Explorer
It was developed by Microsoft in 1994 and released in 1995 as a supportive package to
Microsoft Windows line of operating systems. According to statistics, its usage share from 1999
to 2003-04 was around 95%. Microsoft occasionally releases updates for the previous versions of
IE, which have some enhanced capabilities. IE has come up a preview release of Internet
Explorer 11.
Features: There are regular Microsoft updates that IE supports. Favicon allows an image to
be used as a bookmark. It supports Integrated Windows Authentication. It’s icon is as
follows.
2. Mozilla Firefox
It is owned by Mozilla Corporation and was the result of an experimentation.
'Mozilla Firefox' was officially announced in February 2004. It was earlier named Phoenix,
Firebird, and eventually Firefox. It is the second-most famous browser after Internet
Explorer, as there were around 100 million downloads within a year of its release. Until
November 2008, 700 million downloads were recorded.
Features: As it is an open source software, it allows everyone to access the code. It supports
tabbed browsing that allows the user to open multiple sites in a single window. Session
storage is also an important feature of Firefox, which allows the user to regain access to the
open tabs after he has closed the browser window. It’s icon is as follows.
3. Google Chrome
This web browser was developed by Google. Its beta and commercial versions
were released in September 2008 for Microsoft Windows.
Features: The main standout feature is the malware and phishing warning that the browser
suggests when the user wants to browse a site. Also, there is a user tracking option available
with Chrome. It’s icon is as follows.
16. Write the structure of HTML program.
A. Structure of an HTML Program.
In every HTML program has a rigid structure. The entire web page is enclosed within
<HTML> </HTML> tags. Within these tags two separate sections are created using the
<HEAD> </HEAD> tags and the <BODY> </BODY> tags. These sections are described below.
1. < Head> tag
Information placed in this section is essential to the inner workings of the document and has
nothing to do with the content of the document. With the exception of information contained
within the <TITLE> </TITLE> tags, all information placed within the <HEAD> </HEAD> tags
is not displayed in the browser. The HTML tags used to indicate the start and end of the head
section are:
<HEAD>
<TITLE> </TITLE>
</HEAD>
The <TITLE> tag sets the title of the document which will be displayed in the title bar of the
browser window.
2. < Body> tag
The tags used to indicate the start and end of the main body of textual information are:
<BODY>
</BODY>
Page defaults like background color, text color, font size, font weight and so on
can be specified as attributes of the <BODY> tag. The attributes that the <BODY> tag
takes are:
bgcolor, background, text, etc.,
Example
<html>
<head>
<title>
First Page
</title>
</head>
<body>
This is My First Web Page
</body>
</html>
17. Explain various types of lists used in HTML.
A. LISTS:
Lists are used to list out items, subjects or menu in the form of a list. HTML gives you three
different types of lists.



<ul> - An unordered list. This will list items using bullets
<ol> - A ordered list. This will use different schemes of numbers to list your items
<dl> - A definition list. This is arrange your items in the same way as they are arranged
in a dictionary.
HTML Unordered Lists:
This list is created by using <ul> tag. Each item in the list is marked with a bullet. The
bullet itself comes in three styles: squares, discs, and circles. The default bullet displayed by most
web browsers is the traditional full disc.
Example:
<html>
<body>
<center>
<h2>II YEAR CSE PAPERS</h2>
</center>
<ul>
<li>GFC</li>
<li>ENGLISH</li>
<li>OOPS&JAVA</li>
<li>RDBMS</li>
<li>DCCN</li>
</ul>
</body>
</html>
This will produce following result:
II YEAR CSE PAPERS





GFC
ENGLISH
OOPS&JAVA
RDBMS
DCCN
You can use type attribute to specify the type of bullet you like. By default its is a disc.
Following are the possible way:
<ul type="square">
<ul type="disc">
<ul type="circle">
2.HTML Ordered Lists:
This list is created by using <ol> tag. Each item in the list is marked with a number. By
default The numbering starts from one and is incremented by one.
example:
<html>
<body>
<center>
<h2>II YEAR CSE PAPERS</h2>
</center>
<ol>
<li>GFC</li>
<li>ENGLISH</li>
<li>OOPS&JAVA</li>
<li>RDBMS</li>
<li>DCCN</li>
</ol>
</body>
</html>
This will produce following result:
II YEAR CSE PAPERS
1.
2.
3.
4.
5.
GFC
ENGLISH
OOPS&JAVA
RDBMS
DCCN
You can use type attribute to specify the type of numbers you like. By default its is a generic
numbers. Following are the other possible way:
<ol type="I"> - Upper-Case Numerals.
<ol type="i"> - Lower-Case Numerals.
<ol type="a"> - Lower-Case Letters.
<ol type="A"> - Upper-Case Letters.
3.HTML Definition Lists:
Definition List makes use of following three tags.




<dl> - Defines the start of the list
<dt> - A term
<dd> - Term definition
</dl> - Defines the end of the list
Example:
<html>
<body>
<dl>
<dt><b>LAN</b></dt>
<dd>LAN stands for Local Area Network</dd>
<dt><b>WAN</b></dt>
<dd>WAN stands for Wide Area Network</dd>
</dl>
</body>
</html> >
This will produce following result:
LAN
LAN stands for Local Area Network
WAN
WAN stands for Wide Area Network
18. Discuss briefly about CSS.
A. Introduction to CSS
CSS stands for Cascading Style Sheets. It is a way to divide the content from the layout on web
pages. A CSS (cascading style sheet) file allows you to separate your web sites HTML content
from it’s style. As always you use your HTML file to arrange the content, but all of the
presentation (fonts, colors, background, borders, text formatting, link effects & so on…) are
accomplished within a CSS.
Advantages of CSS:
1. Define the look of your pages in one place rather than repeating yourself over and over again
throughout your site.
2. Easily change the look of your pages even after they're created. Since the styles are defined
in one place you can change the look of the entire site at once.
3. Define font sizes and similar attributes with the same accuracy as you have with a word
processor - not being limited to just the seven different font sizes defined in HTML.
4. Position the content of your pages with pixel precision.
5. Redefine entire HTML tags. Say for example, if you wanted the bold tag to be red using a
special font - this can be done easily with CSS.
6. Define customized styles for links - such as getting rid of the underline.
7. Define layers that can be positioned on top of each other (often used for menus that pop up).
The one disadvantage is:
1. These will only work on version 4 browsers or newer. However, more than 95% of all
browsers live up to that.
1. Explain about CSS selector.
CSS Selectors
CSS Selectors are the names that you give to your different styles. In the style definition you
define how each selector should work (font, color etc.).Then, in the body of your pages, you
refer to these selectors to activate the styles.
Program
<HTML>
<HEAD>
<style type="text/css">
b.headline
{
color:red;
font-size:22px;
font-family:arial;
text-decoration:underline
}
</style>
</HEAD>
<BODY>
<b>This is normal bold</b><br>
<b class="headline">This is headline style bold</b>
</BODY>
</HTML>
Output