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System Development
Life Cycle
System
The
word system is derived from the Greek word System which means an organized
relationship among the functioning components. A system can be defined as any
set of objects and ideas, and their interrelationships, which are ordered to a
common goal or purpose. Examples:-Computer system, library management system,
account system, production system, respiratory system etc.
it
is a set of elements joined together for a common objective. It can also be
defined as the combination of people, devices and methods interrelated in
working towards a common goal. Any system cannot do any jobs without
sub-systems. A subsystem is a part of large system. For example, an organization
is a system and the parts like departments, accounting, information units etc
are sub-systems.
Examples:
business system, computer system, information system, solar system etc. Every
system has boundary within, which it lies and outside of which is its
environment.
In
dealing with a system.
Characteristics
Of System:
a) There is some
specific purpose or function that must be fulfilled or performed.
b) There are a Number of
components that can be identified as the necessary ingredients of the problem;
each component has a variety of attributes that implicitly, physically and
behaviorally are necessary for description.
c) These components are
inter-related in some manner, satisfying interface consistency between the
components.
Management
Information System
The
system in which data is converted to information is called information system.
So, data is the major raw material in information system. MIS (Management
Information System) is the system which provides the information for
decision-making, organizing and controlling operation regarding the integration
of the organization through the process of management. It helps manager of
company to plan and control operation. MIS are made of people, computers,
procedures, database and so on.
Management
is the process or operation carried out by managers.
MIS
: =>Management> Information> System
We
need computer-based information system because:
·
The
size of organization is becoming large. Computer-based information system helps
to run organization efficiently.
·
Same
data can be processed in different ways, i.e., manager can look at the
performance of an organization in different angles.
·
Organizations
are distributed with many branches. So, exchange of information between
branches and organization is essential.
·
Account
package can maintain, update and retrieval of data.
·
Processing
of data in high speed.
Feasibility
study and purpose feasibility study
The
process of analyzing whether the proposal is feasible, or not is called
feasibility analysis. If it is not feasible, we need to look other
alternatives. Feasibility study mainly focus on the demand of the system that
affects the overall development of the information system.
The
aims of feasibility study are:
a) To determine whether
the objectives stated in the assignment brief are reasonably attainable within
the limitations and financial constraints period.
b) To define major
problem areas, so that the system analyst can plan the strategy for the field
investigation.
c) To find areas where
potential exists for making saving in money, time or effort.
d) To determine the
approximate time required for the full:
e) Investigation and
cost.
f) To discover the areas where some specialist
knowledge is needed for the full investigation.
The
different levels of feasibility studies are Technical feasibility, Economical
feasibility, Behavior feasibility, Schedule feasibility.
The different levels of feasibility studies
are:
(1)
Technical feasibility.
(2)
Economical feasibility
(2)
Behavioral feasibility
(4)
Schedule feasibility
1. Operational
feasibility:
It is a measure of how well the solution of problems or a specific alternative
solution will work in the organization. It is also measure of how people feel
about the system
2. Technical
feasibility:
It is a measure of the availability of technical resources (hardware components
or technical equipment). It also studies the availability of the technical
manpower for the project. [If the work performances of the technical manpower
are not experienced, the entire system will be certainly insufficient.)
3. Economical
feasibility:
Economical feasibility measures whether finances (investments) are available
for proposed solution, i.e., it looks at the financial aspects
(cost/effectiveness) of the project. This is often called a cost-benefit
analysis.
4. Schedule feasibility: If a deadline
(time-limit) is established, it is called schedule feasibility, i.e., the
deadline of the project is studied under the schedule feasibility. The schedule
feasibility is also depends upon available manpower and economical condition as
well.
Prototyping
It
is a method of developing software. It is new idea which is economic, easy and
powerful. Prototype means the duplication which may be complete or incomplete.
Prototyping is not a complete program but it is a portion (skeleton) of any
program. It does not contain any logic but only the inputs and outputs.
“Prototype is an extra job in the development” but it helps us when there is
missing data, when we implement system, to avoid the extra money and time.
The
concept of prototyping is that it is practical to test portion of the system
with the ultimate users before the total system is complete. The concept is to
build rapidly a model or prototype and test it under live conditions.
System Development Life Cycle( SDLC)
A
system, as we known, is developed and maintained to meet the requirements
(needs) of an organization. The needs or requirements of the organization,
changes. So, the system must be modified to meet continuous requirements of the
organization When the modifications are minor, they are regarded as
maintenance. But when proposed modification to the system requiring large
expenditures of time, effort and money, they are regarded as project. There are
eight steps (stages) in designing a system which is known as system development
life cycle (SDLC The system analyst is responsible for performing many of
activities in this methodology. The user describes those individuals in the
management and operations of the organization for whom the system is
implemented.
The
stages of SDLC are explained below:
1. Requirement
Determination:
in this first step of design needs or requirements of the organization are
specified or determined. The requirements are arrived at by a consents’ reached
among managers in the organization.
2. Requirement
Specification
(Initial or rough specification After discussing with managers and users, the
system analyst dra up the specifications of user’s requirements by consensus in
understandable language showing what will be the system output
3. Feasibility Analysis: Having drawn up the
rough specifications, the next step is to check whether it is feasible to
implement the system. A feasibility study takes into account various
constraints. The resources needed for implementation such as computing
equipment, manpower and cost are estimate ‘based on the specifications of
user’s requirements. The feasibility report is also given to the management of
the organization.
4. Final specifications: The management of
the organization studies this feasibility report and suggests modifications in
the requirements if any. According to the suggestion, system. anal draws up
final specifications of the system. These specification should be in a form
which can be easily understood by the users,
5. System Design
(Development):
The next step is to develop the logical design of the system. In this, the
logic of the program designed, databases are designed, and program test plans
and an implementation plan are drawn up.
6. System
Implementation:
In this phase, programs are written, database is created, and users are
trained. Systems are installed and tested with operational data.
7. System Evaluation: After implementation
system, it is evaluated (finding out from users if system meets their needs)
and plans for its improvement are drawn up, i.e. evaluating report with
suggestion for improvement is prepared.
8. System Modification!
Maintenance:
After drawing plans for improvement, changes on the system will be made.
Changes may be adding or deleting features to satisfy users’ needs.
Modification / Maintenance is necessary to eliminate errors in the system.
System
Analysis
System
analysis is the process of analyzing a system and trying to find a way to
modify it or create a new system to meet the user’s J need. In other words, the
investigation into system operation and possible changes to the system is
called system analysis.
The
systems are made up of many interrelated tasks. Changes to any one of these
tasks or the addition of new tasks can affect existing ones. Therefore, it is
necessary to understand the system and its problems. This becomes possible to
propose useful change which makes the system more useful. Once system analysis
is completed, system design commences (starts or begins). The main activities
which are undertaken in this phase are:
a) Definition of output
requirements such as contents, layout volume frequency and distribution.
b) Specification of
input data including source, formats, transcription, error checking and
corrections etc.
c) Development of
overall system logic.
d) Identification of data
that are to be stored in master files or working files, record formats, data
elements, data organization, frequency of updating etc.
e) Development of
step-step-by narratives and detailed system flowcharts.
f) Identification of
computer programs and manual procedures required.
g) Preparation of
program specifications such as program functions, inputs, outputs and
processing procedures.
h) Development of
operating specifications.
i) Development of
general test requirements(type of data source, control checks etc)
j) Revision of estimate
of operational costs of systems.
System
Security
System
security means protecting the various resources and information of a computer
system against destruction and . Unauthorized access. Security can be
maintained in two ways:
External
and internal security.
External
security means protecting the computer system against external activities like
thieves, floods, fires, earthquakes and so on. For maintaining external
security,
a) Use security guards
to allow the entry of authorized persons into computer department.
b) Allowing access to
sensitive information to only trusted employees or users.
c) Use backup copies of
data
d) Internal security can
be maintained by
e) User authentication:
User authentication is checked by the system before using the system.
f) Access control: A
computer system has lots of resources and various types of information. All the
resources and information are not for users. So, prohibit the user from
accessing all resources and information that he /she is not authorized.
Waterfall
Model
This
model was introduced by Winston Royce in 1970 and is currently the most
commonly used model for software. The waterfall model describes a development
method that is linear and sequential. Waterfall development has distinct goals
for each phases of development. The waterfall model is simple, easy to learn,
and easy to use. The working results first appear near the end of the process.
The
advantage
of waterfal1 development is that it allows for departmentalization and
managerial control. A schedule can be set with deadlines for each stage of
development and a product can proceed through the development process like a
car in a carwash, and theoretically, be delivered on time. Development moves
from concept, through design, implementation, testing, installation,
troubleshooting, and ends up at operation and maintenance. Each phase of
development proceeds in strict order, without any overlapping or iterative
steps.
The
disadvantage
of waterfall development is that it does not allow for much revision. Once an
application is in the testing stage, it is very difficult to go back and change
something that was not well-thought out in the concept stage.
The
activities and phases of this model are presented as
a) Analysis
b) Requirements
Specifications
c) Design
d) Implementation
e) Testing and Integration
f) Operation and
Maintenance
Prototype Model
This
model is applied when there is an absence of detailed
information
regarding input and output requirement in software.
Advantages:
1.
Helps in reducing risk associated with the project.
2.
There is a great involvement of user in software development
Disadvantages:
This
model is time consuming and expensive. Because if the user is not satisfied by
the developed prototype then a new prototype is developed. This process goes on
until a perfect prototype is developed.
Spiral
Model
This
model was proposed by Bohem in 1988 and is the latest model in SDLC. The spiral
model, also known as the spiral lifecycle model, is a systems development
lifecycle model used in information technology (IT). This model of development
combines the features of the prototyping model and the waterfall model. The
spiral model is favored for large, expensive, and complicated projects.
The
steps in the spiral model can be generalized as follows:
1. The new system
requirements are defined in as much detail t as possible. This usually involves
interviewing a number of users representing all the external or internal users
and other 7 aspects of the existing system.
2. A preliminary design
is created for the new system.
3. A first prototype of
the new system is constructed from the preliminary design. This is usually a
scaled-down system, and represents an approximation of the characteristics of
the final product.
4. A second prototype is
evolved by a fourfold procedure: (1) evaluating the first prototype in terms of
its strengths weaknesses, and risks; (2) defining the requirements of the
second prototype; (3) planning and designing the second prototype; (4)
constructing and testing the second prototype.
5. At the customer’s option,
the entire project can be aborted if the risk is deemed too great. Risk factors
might involve development cost overruns, operating-cost miscalculation, or any
other factor that could, in the customer’s judgment, result in a
less-than-satisfactory final product.
6. The existing
prototype is. Evaluated it the same
manner as was the previous prototype, and, if necessary, another prototype is
developed from it according to the fourfold procedure outlined above.
7. The preceding steps
are iterated until the customer is satisfied that the refined prototype
represents the final product desired.
8. The final system is
constructed, based on the refined prototype.
9. The final system is
thoroughly evaluated and tested. Routine maintenance is carried out on a
continuing basis to prevent large-scale failures and to minimize downtime.
System
Analyst [HESB-2057]
A
person who analyzes the system and identifies its problem to design a usable
system is called System Analyst. The analyst works with users to study their
(users) specific information requirement so that during analysis he can discuss
(talk) with users, how to design a new system that meets these requirements.
The functions of an analyst in designing a system are similar to an architect
in building house.
The
main roles and tasks of A system analysts are
1. Defining Requirement: A system analyst is
responsible to understand the user’s requirements. It involves interviewing
users. The analyst must spend a lot of time talking to users and finding out
how they use the system, any problems they may have with the system and what
they expect from it.
2. Prioritizing
Requirements:
Each user has some special requirements. It may not be possible to satisfy
needs of everyone due to limited computing capacity, availability of
programmers etc. So, the analyst is responsible to set priorities among the
requirements of various users (some of the tasks first and other later).
3. Gathering data and
opinions of users:
The analyst must gather the necessary data with the users help (i.e., must use
of the user’s long experience and expertise). ‘While developing a system, the
analyst continually consults the users and gets their views (opinions).
4. Solving Problem: An analyst must
study the problem in depth and suggest alternate solutions to the management
The relative difficulties in implementing each of the alternatives and benefits
of each must be determined so that a manager can pick what he considers as the
best solution.
5. Drawing up
specifications
(details of design and materials An analyst is responsible to obtain (draw) the
function specification of the system to be designed in a form whic1 can be
understood by users and managers.
6. Designing Systems: Once the
specifications are accepted, the analyst designs the system. The design must be
understandable to the system implementer.
7. Evaluating system: An analyst must
evaluate a system after it has been in use for a reasonable period of time.
Characteristics
of a good system analyst
1. Knowledge of
organizations:
A system analyst must understand the way in which various organization
functions He/she must understand the management structure and the relationship
between the departments in organizations.
2. Knowledge of computer
systems and software:
The analyst must know about computer systems and software. He/she need not be
an expert programmer or computer manager, but know enough technical details to
interact effectively with program designers and computer managers.
3. Good Inter-personal
relations:
An analyst must be able to interpret (explain in a specified manner or explain
the meaning of....), must be a good listener, a good (skill in dealing with
others) and win users over as friends.
4. Ability to
communicate:
An analyst is also required to orally present his design to groups of users. He
must be able to present his thoughts in a language easily understood by users.
5. An analytical mind: A good analyst must
be able to find solutions to problems.
Program
Logic Tools
[HSEB-2066]
Program
logic is the way to solve a specific problem. It generates the idea to solve
problem.
The
programmer use different program design tools to develop the logical sequence
for the solution of the problem. The most commonly used tools are:
1.
Algorithm
2.
Flowchart
3.
Pseudocode
4.
DFD
5.
Decision
Table
6.
Decision
Tree Decision table
A
decision table allows us to identify the exact course of actions for given
conditions. Decision table provides unambiguow decisions, leading to a good
program design. A decision generally’ consists of 2 parts. They are:
(a)
Conditions
(b)
Actions
Decision
table is preferred when one of the large numbers of actions is to be selected.
The action selected depends upon a large .
number
of conditions.
Decision
Tree
Decision
Tree also does more or less same job as decision table except that, it follows
the tree structure and each node of tree denotes conditions. Decision Tree is
more user-friendly than decision table because it provides a graphical
hierarchical diagrammatic view of the conditions and actions.
DOCUMENTATION
AND DOCUMENTATION TECHNIQUE
Documentation
is a process of recording all important information and relevant to the
projects which is used for future reference. The documentation will include a
statement of problem, pseudocode, coding sheets, test data and results.
The
documentation techniques are —
a. Algorithm
b. Flowchart
c. Pseudocode
d. Data Flow Diagram
(DFD) ERD diagram
e. Decision Table
f. Decision Tree
Explanation
of any four of them are:
a.
Algorithm
Algorithm
can be defined as a sequence of instructions designed in a manner that, if the
instructions are executed in the specified sequence, the desired results will
be obtained.
b.
Flowchart
A
flowchart is the symbolic representation of the step by step solution of a
given problem, and it indicates the flow of the entire process, the sequence of
data input, operations, computation decisions, results and other relevant
information, pertaining to a particular problem.
c.
Pseudocode
It
is another programming analysis tool which is used for planning program logic.
It allows programmer to represent the logic of program in manner which may look
like plain English, so anybody can understand it without any difficulty.
d.
Data Flow Diagram
DFD
is the pictorial representation of data flow in any information system. It
gives entire structure of information system such that with the help of DFD we
can easily know the process of information in simple way.
Database Management
System
A
database management system (DBMS) is a collection of interrelated data and a
set of programs to access those data. It is a software system that manages data
stored in the database. It provides effective method of defining, storing and
retrieving the information contained in the database (the primary goal of a
DBMS is to provide an environment that is both convenient and efficient to use
in retrieving and storing database information) i.e. DBMS allows the creation,
modification and utilization of the database. It provides users information
that they required. Some examples of DBMS packages are dBASE, FoxPro, Foxbase,
MS-Access, Oracle, DB2 etc.
Advantages
of DBMS
a) Make an easy to add
new data, modify the database and delete existing data
b) Organize the data in
proper sequence
c) Eliminates redundancy
of data
d) Easy queries of data
in the database —saves user time
e) Allows multiple users
to be active at one time (data in database
f) may be shared among
several users)
g) Protecting data
against unauthorized access
h) Allows the growths of
database system.
Disadvantages:
a)
Cost
of purchasing or developing software
b)
Chances
of losing data
c)
Chances
of data leakage and hacking
d)
Cost
of sharing data
e)
Requires
trained manpower
f)
Cost
of maintenance of software
RDBMS(Relational
Database Management System):
The
database system which stores and displays data in tabular format of rows and
columns, like a spread-sheet, is known as RDBMS. A relational database is made
up of tables that contain data records. Each of the records is composed of
fields. The power of relational databases comes from their ability to store
data with minimal duplication and from their ability to link (relate) data from
different sources, i.e., RDBMS can link the data of one table to the data of
another table through the use of a common field. This later ability (second
one) ability is where the relational database gets its name; relational
databases can easily link two or more fields together. By linking fields, we
can link entire records. Some of the more well-known RDBMS are Oracle, SQL, and
Access etc.
Entity: An entity is an
object or things about which data can be recorded. In other words, it is an
object in the real world that exists and is distinguishable from other objects.
Each person, employee, customer, account etc. are the examples of entity.
Attribute: Attributes are the properties of an
entity; i.e. the attributes of an entity are those facts that need to be stored
about entity. For example, student_name, roll, class, address, phone etc are
attributes of a student.
Field: A field is an
attribute pertaining to an entity, and it is organized as a column in a
database table. In other way, a field is a piece of information about an
element; element may be a person,
Domain: A domain is a set of
values from which the actual values appearing in a gi’en columns are rawn. i.e. for each attribute, there is a set
of permitted values, called the domain of that attribute. In given relation,
for the attribute customer_name, the domain is the set of all customer names.
Tuple
: A
tuple is a collection of one or more attributes. It is a row of information in
a database table that is constructed over a given database schema. It should be
noted that a tuple usually represents some object and its associated data.
Further, a relation is defined as a set of n-tuples.
Relationship:
A
relationship is an association among several entities. For example a deposit
relationship associates a customer with the account hat he/she has
Example:
An example between teacher and student. One teacher has many students, but each
student has only one teacher.
Types
of relationship
(i)
One to one:
A single instance of an entity is associated with a single instance of another
entity. An example where one-to-one relationship might be used as one teacher
teaching only one course.
(ii)
One-to-many:
An instance of an entity (called parent) is associated with several instances
of another entity (called the child). An example of this type can be found by
examining the teacher and class entities
(iii)
Many-to-many:
Many instances of an entity are associated with many instances of another
entity. An example is student and course, Film and Film star etc.
Database
A
database is an organized collection of related information or data, which are
shared and used for multiple purposes. A database can be a Flat File Database,
Relational Database, Distributed Databases etc. The organized information or
database serves as a base from which desired information can be retrieved; many
meaningful conclusions can be drawn, or decisions made, by further reorganizing
or processing these data. A telephones directory is one of the most common
examples of a database where the names of telephone subscribers are given in
alphabetical order. The dictionary is another example of a database in which•
words are arranged alphabetically. Similarly, we come across various other
kinds of databases in our daily life.
Differentiate
between database and DBMS. [HSEB-2064]
Database
a)
it
is collection of data or related information
b)
It
consists of data.
c)
It
is a part of DBMS.
d)
Examples:
Telephone directory, data of S.L.C. examination, payroll system etc.
DBMS
a)
It
is a software package to manage the database.
b)
It
manages data stored in database.
c)
It
is a software system that contains database.
d)
Examples:
FoxPro, Oracle, dbase, Access etc.
Database
administrator. [HSEB-2063]
A
DBA (Database Administrator) is a person who has central control of both data
and programs that access those data oyer the system. A DBA needs the following:
·
Knowledge
of the operating system in which database server is running.
·
Knowledge
of Structured Query Language (SQL)
·
Sound
database design
·
General
understanding of network architectures (for example, Client/Server,
Internet/Intranet, Enterprise)
·
Knowledge
about the database Server.
Responsibilities
of DBA are:
The
DBA is reponsible for ensuring that:
a)
The
data in the database meets the information needs of the organization.
b)
The
facilities for retrieving data and for structuring reports are appropriate to
the needs of the organization.
a) 3) The DBA is
responsible for the data dictionary (data about data or meta- data, i.e. define
the structure of data) and manuals for users describing the facilities the
databae offers and how to make use of these facilities.
b) 4) Another function
of DBA is to supervise the modification (insert, delete and update) of data.
c) 5) The DBA is also
responsible for security of database and requirements of privacy.
d) 6) The DBA is also
responsible for database integrity maintenance (changes made to the database,
do not result in a loss of data).
Database
Model Or Structure Of Database
A
database model is a collection of conceptual tools for describing data and its
relationships. Simply, it is an organizing principle that specifies particular
mechanism for data storage and retrieval. Data models can be classified in the
following categories.
A.
Relational Data
model
The
relational model uses a collection of table to represent both data and
relationships among these d4ta. In relational model, data are organized into
table (i.e. rows and columns). These tables are called relations. Rows of
relations are generally referred as tuples and columns are referred as
attributes. A row of a table represents a relationship among a set of data
values. This model does not use pointer or links.
Advantages
a)
Reduces redundancy
b)
Normalization of database is possible
c)
Easy to delete, update and query record.
Disadvantages
a)
Too
many rules make database non-user friendly
B.
Network data model
In
network model, data are represented by a collection of records and
relationships among data are represented by links, i.e. the collections of
records are links, which can be viewed as pointer. A link is an association
between records. The records are organize4 as arbitrary graph. We can say that Similar
to hierarchical model, each parent can have more than one child, but in network
model, each child can have more than one parent.
Advantages
a)
More flexible than hierarchical as it accepts many to many
relationship.
b)
Searching is faster because of multiple pointers
Disadvantages
a)
Very complex type of data model
b)
Needs long programs to handle relationship
C.
Hierarchical data model
In
the network model, the data are represented by collection of records and
relationships among data are represented by links.
This
is true for hierarchical as well. The only difference is that in
the
hierarchical model records are organized as inverted trees
rather
than arbitrary graphs.
Advantages
a)
More secured because nobody else can see and modify a child without consulting
to its parent.
b)
Searching is fast and easy, if parent is known
Disadvantages
a)
Non-flexible data model
b)
Increases redundancy
Benefits
Of Centralized Database [HSEB-2061, 2064]
(a)
Data reside in a single location. So the cost of devices required in the single
location is lower.
(b)
Database cost is also low.
(c)
Require less man power to operate the database.
(d)
Data security is higher than the distributed database. Due to this, the data
hacking probability is less.
(e)
If any problem arises in the location, then the diagnose method is easy and
take less time.
(f)
Working speed is more than distributed database.
Data
Security [HSEB-2057, 2058, 2061, 2064]
Data
security is the protection of data i.e. preventing the loss of data or misuse,
disclosure or unwanted modification of data.
·
Data
may be lost due to any accident occur in computer or due to infection of virus.
So to prevent from such problem, use of backup copies of data.
·
Use
of password to prevent unauthorized use of computer or unauthorized access to
on-line files.
·
Physical
prevention, restricting access of personnel.
·
Keeping
data under lock and key.
·
Weakness
of operating system security may serve as a means of unauthorized access to the
database. For example, Windows 2000 (windows XP, Linux etc.) provide the most
security than the windows 95/98.
Client
I Server database system:
Client/Server
Data processing activities are fully applied in the computing systems placed in
the network. In a generalize concept, Client PC is the computer from where the
user request for data and information
where as the server provides the requested information. The database
application on the client PC referred to as the “front end system”, handles all
the screen and user input output processing. The “back end system” on the
database server handles data processing and disk access. For example, a user on
the front end creates a query for data from the database server, and the
front-end application sends the request, across the network to the server. The
database server performs the actual search and sends back only the data that
answers the user’s query.
Distributed
Database System
A
simple form of distributed processing has existed for several years. In this
limited form, data is shared among various host systems, via updates sent
either through direct connections on the same network or through remote
connections via phone or dedicated data lines
The
Advantages Of Database System Over Flat File System [HSEB-2o66]
Advantages
of database system over flat file systems are:
a. It is based on the
concept of relationships
b. b. Speed of operation
is very fast because records (or “rows”) are typically read directly by means
of an index.
c. c. Uses concept of a
table
d. d. Easy for editing,
searching, adding and deleting records.
e. e. Chances of
repetition of data is very is low.
f. f. Multiple users can
use the database at the same time(i.e. sharing of database)
g. g. Easily allows the
growth of database system.
h. h Provide stronger
security than flat file system.
DDL(Data Definition Language) [HSEB-2058]
A
database schema is specified by a set of definitions expressed by a special
language called data-definition language (DDL). The result of compilation of
DDL statement is a set of tables that is stored in a special file called data
dictionary. A data dictionary is a file that contains metadata that is data
about data.
DDL
is a special language, which supports the definition or declaration of database
objects, i.e., it is used to specifr the data in the database. (It allows users
to define the structure of data in the database). This language is not a
procedure language. DDL includes statements for creating, manipulating,
altering and deleting the Tables and Views. Some of data definition commands
are
Create
Table, Create View, Alter Table and Drop Table (delete table).
CREATE
TABLE student roll number (3), name varchar (10), address varchar (10), phone
number (6));
CREATE
VIEW student AS SELECT name, phone FROM
student
WHERE
Roll< 20;
So,
data definition language is used when the database is designed or modified.
DML(Data
Manipulation Language) [HSEB-2059]
The
data management system also provides a data manipulation language to access and
us the stored data in applications. A data manipulation language (DML) is a language
that enables users to access or maintain data as organized by the appropriate
database systems. Data manipulation means
(a)
insertion
(c)
retrieval
(b) deletion
(d)
modification
In
general, the DML is very flexible in that it may be used by itself to create,
read, update, and delete records; or its commands may be called from a separate
host programming language such as visual basic or java.
A
data manipulation language is a language that enables users to access or
manipulate data as organized by the appropriate data model, i.e., DML is used
to update the database by adding new data or modiI or delete the existing data.
Some
of the Data Manipulation Commands are:
INSERT
INTO student VALUES (12, ‘Ram’, ‘Kalimati’, 270175);
DELETE
FROM student
WHERE
address = ‘Kalimati’;
DELETE
FROM student; ->This command deletes all rows
SQL(Structured
Query Language) [HSEB-2057, 2062]
A query is a more powerful type of filter that
can gather information from multiple tables is a relational database. For e.g.
The query can include field names such as “customer” and “city’ from a customer
table and “order date’ from the order table.
Basic
structure:
SELECT
fieldi, field2 FROM tables name WHERE condition Query from one table:
SELECT
name, phoneno FROM stud_detail WHERE sec =“A”
Data
integrity [HSEB-2058]
The
term data integrity refers to validity of data contained in a database.
Database integrity can be reduced in many ways including input typing errors,
hardware malfunctions and data transmission errors. To avoid data integrity
errors, database, programs should use data validation procedures, which define
, acceptable ranges for each field in record. If user tries to input data is
out of this range, an error message is displayed.
Data
dictionary [HSEB-2O58,2O62]
A
data dictionary is a file that contains metadata i.e., data about data. It
stores the description of structure of data within database. The description of
the structure of data includes the table names that contain data, the column
names, the data types and width of column. So, data dictionary is consulted
before actual data are read or modified in the database system. Data Dictionary
is created when a database is created. The DBMS automatically updates the data
dictionary. It consists of a set of, tables and views, which is a reference for
all database users.
ERD
[HSEB-2058)
The
overall structure of a database can be expressed graphically by an E — R
diagram which consists of the following components:
Rectangles,
which represent entity sets.
Ellipses,
which represent attributes
Diamonds,
which represent relationship among entity sets
Normalization
[HSEB-2060,2065}
Normalization
is the process of breaking down or decomposing a complex relation int simple
relations. It reduces redundancy (unnecessary repetition of data) using the
principle of non-loss decomposition. Non-loss decomposition is the reduction of
a table to smaller tables without loss of information.
As
the time passes, there will be need for most databases to grow by adding new
attributes. Tuples will be added and deleted. Information stored may undergo
updation also. In such situations, the performance of a database is entirely
dependent upon its design. A bad database design may lead to certain
undesirable things like repetition of information, inability to represent
certain information, loss of information etc.
So.
The normalization helps one attain good database design by avoiding these
undesirable things.
Normalization
results in the formation of tables that satisfy certain specified constraints
and represent certain normal forms. Normal forms are table structure with
minimum redundancy.
1.
First
Normal form (1NF)
2.
Second
Normal form (2NF)
3.
Third
Normal form (3NF)
1.
First Normal Form (1NF): - A relation R is in
INF if and only if all underlying domains of the relation contain atomic values
i.e. in every tuple of the relation R, each attribute must have a value. Any
normalized relation is in 1NF.
2.
Second Normal Form (2NF): - A relation R is in
second normal form (2NF) if and only if i i in 1NF and every non-key attribute
is fully dependent on the primary key. [An attribute is a non-key if it doesn’t
participate in the primary key).
3.
Third Normal Form (3NF):-A relation R is said to be in
third normal form if and only if it is in 2NF and every non-key attribute is
non-transitively
dependent
upon the primary key.
The
third normal form overcomes all the problems of 2NF.
So,.
to overcome the problems in book relation, we have to break it
into
two relations.
Networking
A
computer network is a group of two or more computer systems linked together and
ready to communicate with each other and allows data to be transmitted from one
machine to another. In other words, network is a group of computers connected
by cable or other media so that they can share information/resources.
Computer
network enables sharing of information, sharing of resources (i.e. hardware and
software) and provides centralized administration and support.
Advantages
of network
a)
Sharing of information
The
ability to share data and information to users or Computer connected to
computer network. For example, network based e-mail
b)
Sharing of resources (both hardware and software)
It
is possible to share resources like files, hardware. A single hardware like
printer can be shared and used between multiple users at the same time as well
as a single file can be shared between multiple users.
c)
Centralized control
Network
administrator can perform administrative tasks on any Computer on the network
from a single location. Also it is more efficient for personnel to support one
version of OS or application that to oversee a number of individual and unique
system and steps.
d)
Backup and recovery
Generally
the server is a placed in a secure place and a good mechanism is providing for
backup of data. If the data is lost accidentally or due to any other reason in
clients, then it is possible to restore them from the server
Disadvantages
of network
a)
Data security
We
are using networking for data communication them it is not possible to make our
data secure from example threats, sometimes the data between communication is
hacked and by third party
b)
Require manpower
Special
skilled manpower is required to operate rate networking system
Types
Of Network
1.
Local Area Network(LAN)
2.
Metropolitan Area Network(MAN)
3.
Wide Area Network( WAN)
1.
Local Area Network [HSEB 2057, 2062, 2065]
Any
collection of interconnected computers that is located within small area, like
an office or a building or school or colleges or an organization is called
Local Area Network (LAN) .LANs are privately-owned network within a single
building up to few kilometers in size. Data and hardware sharing between users.
Computers are connected through inexpensive cables (twisted-pair or co-axial
cable etc) .It transfers data at high speed (i.e. much faster than data can be
transmitted over a telephone line).LAN architecture consists of cables,
topology, protocol and network interface hardware.
2.
Metropolitan Area Network
MAN
is a network that is larger than LAN. It is called metropolitan since it
normally covers the area of a city or town. It provides network communication
between different business houses or bank branches located at different areas
or localities within the city. It might be either private or public. Many heterogeneous
systems can be interconnected in this system. Computers are connected through
telephone lines and modems. This ntwork can use guided or unguided media. The
range could be up to 100 KMs. It has very high chances of data leakage or
security break.Example: cable TV network
3.
Wide Area Network (WAN) or Long Haul Network (LHN)
A
WAN is a computer network that communicates over a long distance such as across
a city or around the world. (That is, it spans a relatively large geographical
area; spread over states or countries). For the data communication, they use
telephone lines, microwave link or satellite communication channels rather than
through a single physical cable. They are owned by different organizations. It
is the combination of many different types of LAN and MAN networks, so it has
massive amount of heterogeneous systems. For example: Internet
Topology
and different types of LAN
topologies.[HSEB 2060, 20611]
Network
Topology is the way of connecting the computer in LAN or way of cabling in
networking. That is, the way in which the connections are made is called
topology of the network. The major goal of topology is to find out the most
economical and efficient way to connect all the users to the network resources.
The
different types of LAN topologies are:
A.
Bus Topology
B. Star Topology
C. Ring Topology
D.
Tree Topology
E.
Mesh Topology
A.
Bus Topology [HSEB 2057, 2060,
2061, 2062, 2065]
A
bus topology is also known as linear topology. It consists of
several
computers that are attached to a common cable called a bus or trunk, which is a
backbone for the network.
In
bus topology, all the computers are attached to the same communication channel.
Server is located at on both side and terminator id located on other side of
the bus to indicate that the network is not available beyond that point.
Coaxial is used for media and T-Connector is used to terminate the data. Its
maximum speed is 10 mbps.
Advantages:
·
It
is a simple, reliable and easy to use -
·
It
is easy to extend (any number of computers can be connected by using a
connector in the bus).
·
Since
it uses co-axial cable, it is less expensive than other arrangement.
Disadvantages:
·
If
the cable fails, then the entire system fails to respond to the user.
·
Since
the cable is one, fault finding and troubleshooting becomes very difficult.
·
Data
traffic is high; Data collision is high
B.
Star
Topology
In
star topology, all the computers are connected to a centrally located device
called a ithub This center node (hub) is connected to a powerful central computer
known as server. Multiple computers are connected to host computer in star
topology. That is. the computer in the network are not linked directly to each
other and communicate only through the host computer. The routing function is
performed by host computer, which centrally controls communication between any
two other computers by establishing a logical path between them.
Advantages:
It
is flexible (Easy to add and remove computers)
Easy
to find fault as it uses hub
The
cable (one computer) failure does not halt the entire network
Disadvantages:
It is more expensive than bus topology as it
requires extra cables and other controlling devices.
Failure
of the Hub or server makes the entire system disturbed
C.
Ring Topology
In
this topology, the cabling runs from computers to
composters
without any endpoint to form a loop, i.e., data flows in
circular
manner through the ring cable. It is based on peer-to-peer
architecture.
A ring topology passes data in only one direction. So
the
failure of one node can affect the entire network.
Advantages:
Short
cable length than star topology
There
is no dependency on central node
Less chance of data collision as data travels
Disadvantages:
Failure of any one computer on the network
disturbs the entire system
Not
flexible (adding and removing the computers are difficult)
Difficult
to diagnose faults (whenever any terminal gets failed that will affect all
others, so need to check a series of adjacent
D.
Tree Topology
The
tree topology arranges computers in a hierarchical structure in order to allow
greater control and easier troubleshooting. So tree network is also known as
Hierarchical network. The computer in upper level acts as server and at lower
level acts as client. This type of network mostly used in the organization
where headquarters communicate with regional office and regional offices
communicate with district offices and so on.
Features:
·
It
is easy to extend
·
Dependent
on root
(If
main device fails to operate, the entire network is disturbed)
E.
Mesh Topology
In
mesh topology, every computer has a dedicated link to every other computer. If
any of the computer is down then other computers can still continue to work. It
is very much complex to implement and hard to find out the fault.
>
It is expensive, as it requires a lot of I/O ports
Network
Architecture and client-server Network, and peer-to-peer networking.
[HSEB-2066]
Network
topology refers to the way in which nodes of a network are linked together. It
determine data which may be used between any pair of nodes in the network.
A.
Peer-to-Peer Architecture:
In
peer-to-peer network, computers are connected individually in pair (one to one
connection). There is no dedicated server. All the computers are equal, termed
as peers. Each computer on the network has the capability to share data and
resources with other computers. In other words there is no central authority
that determines the network’s resources sharing policy.
B.
Client-Server Architecture: (server-based) [HSEB 2058, 2063]
This
is a network architecture in which each computer on the network is either a
client or a server. Each client (computer using central resources (server)) is
connected to a centrally located dedicated computer called server. Serves are
powerful computers, which provide services to other computers. They control
data as well as printers and other resources that clients need to access. The
server must be faster and more storage capacity to contain all the data, needs
to be shared to the clients.
There
are different types of servers.
1.
File servers: Managing files or disk drives
2.
Print server: To handle printing request.
3.
V Communication server: They are setup to handle remote users dialing into your
network.
4.
Mail Server: Specially setup to handle client’s email Advantages: centralized
security, easy accessibility.
Client:
Computer
that uses the services that a server provides. The client is less powerful than
server
Server: Powerful computer
that provides services to other computers on the net.
Transmission
Media
Transmission
media As the pathway through which network data flow. There are two types of
media and these are:
(A)
Guided / Wired Media (B)
Unguided I Wireless Media
(A)
Guided / Wired Media
The
way to transfer data from one place to another with the help of wire is called
wired media. Examples : Twisted Pair, Coaxial Cable, Fiber Optic.
(a)
Twisted Pair Cable: A
twisted pair wire consists of two bunches of thin copper wires, each enclosed
separately in a plastic insulation, then twisted around each other to reduce
interference by adjacent wires.
(b)
Coaxial Cable :
Coaxial cable (commonly called ‘coax’) are group of specially wrapped and
insulated wire lines, which are able to transmit data at high rates. They
consists of a central copper wire surrounded by PVC insulation over which a
sleeve of copper mesh is placed. The metal sleeve is again shield by an outer
shield of thick PVC material. The signal is transmitted by inner copper wire
and is electrically shielded by metal sleeve. Coaxial cable offer much higher
bandwidth than UT? cables and are capable of transmitting digital signal at
rates of 10Mbps. They are extensively used in long distance telephone line and
as cable for cable TV.
(c)
Fiber optic:
Fiber optics are hair-thin threads of glass, plastic or silica which can serve
as a data transmission medium as copper wire or coaxial cables. Fiber optic can
transmit data at much higher speed than copper wire or coaxial cables. Fiber
optic transmit light signal instead of electrical signals. Fiber optic is made
of glass, plastic or silica.
Physically,
fiber optic cable consists of three concentric layers - the inner core, a
cladding around it and outer protective coating. The inner core consists of a
bunch of optical fiber (has diameter of 8 to 200 micro meters)
(B)
Unguided I Wireless Media
(i)
Microwave system
Microwave systems transmit high-speed radio
signals in a line-of-sight path between relay stations (i.e., transmission from
one antenna to another usually placed on top of buildings, towers, hills and
mountain peaks). Microwave system transmits high- speed radio signals in a line
of sight path between relay stations spaced approximately 25 to 35 miles apart.
It has a much lower error rate and communication links can be made over large
distance.
(ii)
Communication satellite [HSEB 20621]
Although
radio transmissions do not bend around the surface of the earth, Radio
frequency technology can be combined with satellites to provide communication
across longer distance. Satellites have now become an integral part of the
worldwide communications system. It is nothing more than microwave (radio)
relay station.
(iii)
Infrared
The
wireless remote controls used with appliances such as televisions and stereos
communicate with infrared transmissions. Infrared is limited to a small area
(e.g., a single room), and usually requires that the transmitter be pointed
toward the receiver. Infrared hardware is inexpensive compared to other
mechanisms, and does into require an antenna.
(iii)
Infrared
The
wireless remote controls used with appliances such as televisions and stereos
communicate with infrared transmissions. Infrared is limited to a small area
(e.g., a single room), and usually requires that the transmitter be pointed
toward the receiver. Infrared hardware is inexpensive compared to other
mechanisms, and does into require an antenna.
iv)
Bluetooth
Bluetooth
technology that enables short- range wireless connections between desktop and
notebook computers, handhelds, personal digital assistants, mobile phones,
camera phones, printers,
digital
cameras, headsets, keyboards and
even
a computer mouse.
OSI/ISO
model of networking. [HSEB-20661]
All
network are based on a theoretical model called the open system Interconnection
model designed by ISO (International standard organization) in 1982. It is also
known as ISO/OSI standard, which defines how network devices interact with each
other, i.e, it describes how information from a software application in one
computer moves through a network medium to a software application is another
computer. The OSI model works on a layer approach (conceptual model composed of
seven layers), where each layer is responsible for performing certain network
functions.
There
are distinct seven layers.
a.
Physical Layer:
b.
Data- Link Layer:
c.
Network layer:
d.
Transport layer:
e.
Session layer:
f.
Presentation layer:
g.
Application layer:
a.
Physical Layer:
Physical layer is the lowermost layer of the model. It represents physical
aspects (elements) of the network, i.e, basic network hardware. The network’s
transmission lines (thecables that connect all the computers of the network)
connections are parts of the physical layer.
b.
Data- Link Layer:
This layer specifies how to organize into frames (the form of a packet that the
underlying hardware accepts and delivers) and how to transmit frames over a
network. This layer takes data frames or messages from the Network layer and
provides for actual transmission. At the receiving computer, this layer
receives the incoming data and sends it to network layer for handling. It
provides error- free delivery of data between the two computers by using
physical layer.
c.
Network layer:
This layer defines how addresses are assigned and how packets are forwarded
from one end of network another. It is responsible for finding a path (route)
through the network to the destination (for addressing messages and data). So
the data are sent to correct destination.
d.
Transport layer:
This layer is responsible for reliable transfer of information across the
network. It ensures that the delivered (transmitted/received) data is error
free, in sequence and with no loss or duplication.
e.
Session layer:
This layer specifies how to establish a communication session with a remote
system. [It allows two applications to establish, use and disconnect a
connection between them called a session)., *This layer negotiates connections
between processes or applications on different computers. As such, this layer
handles details such as account names and passwords.
f.
Presentation layer:
This layer is responsible for text formatting and display code conversion
(i.e., data displayed in red color by the sending device are also displayed in
red by the receiving device). It is the layer that can change data itself
(.doc, .xls, .bmp etc) are converted into same extension.
g.
Application layer:
The highest layer of the OSI model and is the only layer that user will operate
in. it acts as the interface between the actual software application and the
communication process. It represents applications like E-mail, databases etc.
Protocol [HSEB 2058, 2063]
Protocols
are a set of rules that control transmission (sending and receiving) of
signals. In other words, it is a language of networking by which computers
communicate with each other.
Protocol
defines a set of commands which one machine sends to another. If message is too
large, protocol will split it up into several packets and make sure that they
all arrive correctly. The
most
commonly used protocols are
1.
TCP/IP: (Transmission Control Protocol/Internet Protocol)
>Used
in WAN and LAN
>
The Internet is based on TCP/IP
2.
HTTP: (Hyper Text Transfer Protocol)
>
To transfer hypertext or wt documents
>Hypertext
is text that is specially coded using standard system called HTML (Hyper Text
Markup Language)
3.
FTP: (File Transfer Protocol)
>Part
of TCP/IP
>Enables
files to be transferred between computers
4.
Telnet: This protocol enablesone computer to connect with another computer
5.
NetBeui: (NetBios User Interface)
> Mostly used in
LAN.
Other important questions
Other important questions
What
do you mean by IT? Explain the advantages and disadvantages of IT. [HSEB-2 062]
The
technology which is used for processing information using telecommunication,
electronic devices and software to store, process, transmit and retrieve the
information is known as information technology (IT). It consists all the
resources related with installation, implementation; enhancement of information
systems and applications.
Advantages
of IT
(a)
It has increased great amount of employment opportunities.
(b)
It has speedly increased global communication like e-mail, internet.
(c)
It makes task easier to find out and work out.
(d)
It increased the social and financial (economic) status of people.
Disadvantages
of IT
(a)
Need well trained manpower to use it
(b)
Higher insecurity
(c)
Require update of new technology which is expensive
(d)
Slow processing of data
What
do you mean by c-commerce? Explain different types of c—commerce. [HSEB.-2058,
2060, 20661
Electronic
commerce is a business through electronic media. Ecommerce is a method of
buying and selling products and services electronically. The processes in
E-commerce include enabling a customer to access product information, select
items to purchase and purchase item securely.
In
another words, e- commerce is one of the most important aspects of the
Internet, which allows people to exchange goods and services immediately and
with no barriers (obstacle) of time or distance Any time of the day or night,
you can go online and buy almost anything you want.
There
are different types of E-commerce:
1.
Business-to-Business E-commerce: This type refers to a company selling or
buying from other companies electronically.
2:
Business to Customer E-commerce: In this type, the company establishes a web
site on the Internet and put information about products and services, allow
customer to order these from web site and also provide customer support services.
3.
Digital Middle Man:
In this type, a company provides information of the products and services of
different companies to the visitors, allowing them to do comparisons and select
the best one. The digital middle man takes some charge from each transaction.
Write
impact of c-commerce in our society. [HSEB-2060]
Generally
the market of c-commerce is growing day by day in the word. B-commerce is used
for updating the business on the net.
Impact
of c-commerce on the society.
(a) It is a tool for
providing more opportunity to the people to do their business in wider range.
(b) By using internet at
one place, one can get lots of thing by ordering the required matter.
(c) It is changing the
traditional business and saving the time for people, and also help the
companies to do their marketing or selling or buying goods from other
companies.
(d) It is also used for
ticket or hotel etc. reservation.
What
are the advantages and disadvantages of c-commerce?
Advantages
of E-commerce
·
Advertisement
of any company (information about varieties of items)
·
Online
shopping.
·
Easy
& save time and money.
Disadvantages
of E-commerce
·
High
cost (telephone and electrical bill)
·
Server
co-location (Separate server for database, every time online, an engineer of
computer professional is required)
What
is Usenet ? What are the uses of Internet? List them.
The
usenet service allows a group of Internet users to exchange their
views/idea/information on some common topic, which is of interest to all the
members belonging to the group.
Uses
of Internet
(a)
On-line communication
(b)
Software sharing
(c)
Exchange of views on topics of common interest
(d)
Posting of information of general interest
(e)
Product promotion
(f)
Feedback about service
(g)
Customer support services
(h)
On-line journals and magazines
(i)
On-line shopping
(j)
World wide video conferencing
Define
the term multimedia. Explain the application area of multimedia. [HSEB-2063]
Multimedia
is the combination of audio, video, text and images into an interactive
computer environment. The aim of multimedia systems is to provide a creative
and effective way of producing, storing and communicating information. The
application areas of multimedia are marketing, training, education,
entertainment etc. The multimedia system is composed of several items:
1.
A
small desktop computer with high-resolution graphics color monitors.
2.
A
stereo audio system (sound card with external speaker)
3.
CD-ROM
disk units (disk + drive)
4.
Video
cameras
5.
Color
graphics printers and scanners.
Application
of multimedia are:— [HSEB-20601]
(a)
Multimedia presentation : Multimedia presentation can be used to better explain a
subject matter to the students, because it enhance the comprehension capability
of students. It is extremely effective in getting across new ideas and
concepts.
(b)
Entertainments :
Multimedia technology is used by entertainment industry as in games, films,
cartoons, animation, sound effects etc.
(c)
Software: Multimedia is used for training purpose or guide. So users can
operate software without the help of trainers.
(d)
Business communication: Multimedia is very powerful tool for enhancing the
quality of business communication.
(e)
Multimedia web page:
Multimedia feature in web page make more attractive, user friendly.
(f)
Public access:
Multimedia is applied in public access field as displaying boards, electronic
voting machines etc.
(g)
Multimedia conferencing : Multimedia conferencing refers to a system that
simulates face-to-face interactions among participating users, located far from
each other, as if they were sitting and discussing in a single room.
What
hardware devices are required to make PC suitable for multimedia? [HSEB-2058]
Minimum
requirement of multimedia computer is
(a)
Intel Pentium processor or any process with MMX
(b)
32/64 MB RAM / technology ÷ graphics accelerator
(c)
Keyboard, Mouse, CD-ROM drive
(d)
4 GB Hard disk
(e)
Sound card with external speaker and microphone
(f)
SVGA display (colour monitor)
(g)
Voice display facility (built-in)
What
is computer animation? How is it used in film making industry? [HSEB-2057]
Computer
animation refers to any sequence of visual changes in a scene, i.e. it is a
series of images that are displayed in a sequence. In addition to changing
object position with translations or rotations, a computer-generated animation.
could display variations in object size, color, transparency or surface
texture. Advertising animations ‘often transition one object shape into
another. For example, transforming a can of motor oil into an automobile
engine. Computer animation can also be generated by changing camera parameters
such as position orientation and focal length. We can also produce computer
animations by changi8ng lighting effects.
What
is Artificial Intelligence (Al)? What are its application areas?
Al
is the study of how to make the computers think and perform. The ability of
computer to understand natural language, speak command, capacity to see
surrounding and have thinking power, is called Artificial Intelligence (Al).
Application
areas of AT: [HSEB-20601]
(a)
Expert systems: An expert system is software based on
certain concepts of Al that acts as a consultant or an expert, in a specific
field, topic or discipline to solve a problem or make a decision. Expert
systems are also referred as knowledge-based systems. They can offer opinions,
suggest possible diagnoses and suggest various solutions to a problem.
(b)
Robotics: Robotics is• the area of study dealing with
the design, construction and operation of robots. A robot is a machine that can
be programmed to carry out a complex task. Robots are used for dangerous jobs,
such as bomb disposal, ocean exploration, outer-space probes, cleanup of a
chemical or nuclear accident etc.
(c)
Voice recognition: The computer with voice recognition accepts
data or instruction by having commands spoken into the computer’s microphone..
(d)
Problem solving: Problem solving is the process of
identifying a problem, recognizing its major characteristics, formulating a
solution plan, dividing the problem into smaller parts, assigning those parts
to be solved, solving each part and finally combining the individual solutions
into the solution of the original problem
(e)
Natural language processing (NLP): It is the ability
of the computer to understand and translate natural (everyday) language.
(f)
Logic and inference: Al is used to make deductions and
then to draw inferences.
(g)
Search:
·
finding
an object within a collection of objects.
·
finding
a preferred answer or best answer to a problem.
·
finding
the winning strategy in a game
·
finding
a sequence of operations by which to solve a problem (puzzle)
What
is cyber law? Mention the area to cover. [HSEB-2061, 2062, 2064, 2065]
Cyber
law is a generic term, which refers to all the legal and regulatory aspects of
Internet and the World Wide Web. Anything concerned with or related to or
emanating from any legal aspects or issues concerning any activity of net users
in and concerning Cyberspace comes within the scope of Cyber law. The Cyber Law
is globally more complicated than traditional laws owing to the reason that the
range of activities which are to be governed by these laws are largely
technology driven. an area which is dynamically changing and is beyond anyone’s
control.
Cyber
law covers laws relating to the following:—
(a)
Electronic and Digital signature
(b)
Computer crime
(c)
Intellectual property
(d)
Data protection and privacy
(e)
Telecommunication laws
What
is cyber crime? List common types of cyber crime.
Computer
or Cyber crimes are considered as illegal, unethical or unauthorized behavior
of people relating to the automatic processing and transmission of data, use of
Computer Systems and Networks. Cyber crimes may be considered as:
·
Unlawful
access to data in computers (theft of information)
·
Unauthorized
use of computer services
·
Changing
and damaging data in computer
·
Possession
of device to obtain unauthorized telephone facilities,
·
Interferences
with business by destruction or damage of computer
