SDLC(Software/System Development Life Cycle):
It is a well defined process by
which a system is planned, developed and implemented. The system development
starts with the requirement for improving their business system.
There are following activities involves
in SDLC :-
·
Preliminary
Investigation (Problem Identification)
·
Feasibility
study
·
System
analysis
·
System
designing
·
Development
of software
·
System
testing
·
Implementation
& Evaluation
·
Maintenance
1.
Preliminary
Investigation OR Problem Identification:
One
of most difficult task of the system analyst is identifying the real problem of
the existing system. It defines the user requirements or what the user expects
from the new system. This also includes the rough idea of the resource
requirements as well as estimated time for completion and number of persons
expected to be involve in each phase.
Problem
identification helps in :-
i.
Defining a problem
ii.
Setting proper system goal
iii.
Determining the boundaries of the project by
considering the limitations of available resources
2.
Feasibility
study:
It
determine the possibility of either improving the existing system or developing
the complete new system. It helps to obtain an overview of the problem and to
get rough assessment of whether physical solution exist. The purpose of
feasibility study is to determine whether the requested system successfully
realizable.
There
are four aspects of feasibility study :-
i.
Technical feasibility
ii.
Economical feasibility
iii.
Operational feasibility
iv.
Behavioural feasibility
i.
Technical
feasibility:
It
involves the required and existing computer system, hardware, software & to
what extent it can support the proposed application.
It
answers following questions :-
o Whether the
system can be carried out with existing equipments ?
o Whether the
existing software is enough ?
o If a new
technology is required how best it can be implemented ?
ii.
Economic
feasibility:
It
involves post benefit analysis to determine the benefit and savings that are
expected from new system and compared with costs. It benefits out weight cost
then decision is made to design and implement new system.
iii.
Operational
feasibility:
It
concerns with human, organisational and political aspects. It covers technical
performance as well as acceptance within the organisation. It determines the
general attitude and job skills of existing personals and whether any
restructuring of jobs will be acceptable to the current user.
iv.
Behavioural
feasibility:
It
includes how strong the reaction of staff will be towards the development of
new system that involves computer’s use in their daily work. So resistant to
change is identified.
3.
System
analysis:
It
involves detailed understanding of all important facts of the business area
under investigation. This require data collection from a verity of sources such
as questionnaires, forms, interviews, study of existing documents. It can be
involved the direct observation in the organisation and collected documents to
understand the whole existing system.
4.
System
designing:
In
this process the primary object is to identify user requirements and to build a
system that satisfies these requirements. Design of the system is mainly the
logical design that can be sketch on a paper or on a computer. It includes
physical design elements, describes the data to be inputted.
The
process involved in manipulation of data & output design represents:-
i.
File structure, storage devices etc
ii.
Database is also designed in this phase
iii.
Changes to be made in the organisational structure of
the firm are outlines
iv.
Input, Output, files, forms and procedures are planned
v.
Finally standards for testing, documentation, system
control are designed.
5.
Development
of software:
Development
is a phase where detailed design is used to actually construct and build the
system. In this phase the system is decided whether to buy commercial software
or to develop new customized program with the help of the programmers. The
choice depends upon the cost of software and cost of programming.
6.
System testing:
Testing
is a process of making sure that the program performs the intended task. Once
the system is designed it should be tested for validity. During this phase the
system is used experimentally to ensure that software does not fail and it will
work according to its specification. It is tested with special test data.
7.
Implementation
& Evaluation:
This
is the final phase of development. It consists of installing hardware,
programs, collecting data and organizing people to interact with and run the
system. In this phase user actually starts using the system therefore it also
involves training of users and provides friendly documentation.
Evaluation
is the process of verifying the capability of a system after it put into
operation to see whether it meets the objective or not. It includes response
time, overall reliability and limitations user behaviour.
8.
Maintenance:
It
is process of incorporating changes in the implemented existing system.
i.
Enhancement:
Adding
new functions or additional capability of the system.
ii.
Adaptation:
Customizing
the software to run in a new environment.
iii.
Correction:
Correcting
the bugs in the existing software.
Great chart to guide anyone interested in using this method of approach. SLDC has tons of value to offer - going through the process will certainly help you maximize your resources as well as eliminate the "unnecessary".
ReplyDeleteSimple and easiest way to understand SDLC is -
ReplyDeleteRequirement analysis for gathering information -> Design -> coding/Implementation -> Testing -> Maintainence .
thank buddy....it helps me a lot becoz i m too a mlsu student
ReplyDeleteI got so much help from these notes in my MBA syllabus thankyou so much for updating these notes
ReplyDeleteGreat Blog!! That was amazing. Your thought processing is wonderful. The way
ReplyDeleteyou tell the thing is awesome. You are really a master in Software Development.