Software Development Life Cycle

 

Software Development Life Cycle, SDLC for short, is a well-defined, structured
sequence of stages in software engineering to develop the intended software
product.

SDLC Activities

SDLC provides a series of steps to be followed to design and develop a software
product efficiently. SDLC framework includes the following steps:

Communication

This is the first step where the user initiates the request for a desired software
product. The user contacts the service provider and tries to negotiate the terms,
submits the request to the service providing organization in writing.

Requirement Gathering

This step onwards the software development team works to carry on the project.
The team holds discussions with various stakeholders from problem domain and
tries to bring out as much information as possible on their requirements. The
requirements are contemplated and segregated into user requirements, system
requirements and functional requirements. The requirements are collected using
a number of practices as given -

1.  studying the existing or obsolete system and software,
   
2.  conducting interviews of users and developers,
   
3.  referring to the database or
   
4.  collecting answers from the questionnaires.

Feasibility Study

After requirement gathering, the team comes up with a rough plan of software
process. At this step the team analyzes if a software can be designed to fulfill all
requirements of the user, and if there is any possibility of software being no more
useful. It is also analyzed if the project is financially, practically, and
technologically feasible for the organization to take up. There are many algorithms
available, which help the developers to conclude the feasibility of a software
project.

System Analysis

At this step the developers decide a roadmap of their plan and try to bring up the
best software model suitable for the project. System analysis includes
understanding of software product limitations, learning system related problems
or changes to be done in existing systems beforehand, identifying and addressing
the impact of project on organization and personnel etc. The project team analyzes
the scope of the project and plans the schedule and resources accordingly.

Software Design

Next step is to bring down whole knowledge of requirements and analysis on the
desk and design the software product. The inputs from users and information
gathered in requirement gathering phase are the inputs of this step. The output
of this step comes in the form of two designs; logical design, and physical design.
Engineers produce meta-data and data dictionaries, logical diagrams, data-flow
diagrams, and in some cases pseudo codes.

Coding

This step is also known as programming phase. The implementation of software
design starts in terms of writing program code in the suitable programming
language and developing error-free executable programs efficiently.

Testing

An estimate says that 50% of whole software development process should be
tested. Errors may ruin the software from critical level to its own removal.
Software testing is done while coding by the developers and thorough testing is
conducted by testing experts at various levels of code such as module testing,
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program testing, product testing, in-house testing, and testing the product at
user’s end. Early discovery of errors and their remedy is the key to reliable
software.

Integration

Software may need to be integrated with the libraries, databases, and other
program(s). This stage of SDLC is involved in the integration of software with
outer world entities.

Implementation

This means installing the software on user machines. At times, software needs
post-installation configurations at user end. Software is tested for portability and
adaptability and integration related issues are solved during implementation.

Operation and Maintenance

This phase confirms the software operation in terms of more efficiency and less
errors. If required, the users are trained on, or aided with the documentation on
how to operate the software and how to keep the software operational. The
software is maintained timely by updating the code according to the changes
taking place in user end environment or technology. This phase may face
challenges from hidden bugs and real-world unidentified problems.