Software Development Life Cycle

SDLC

Software Development Life Cycle, in other words SDLC, is a series of steps in software engineering to develop the intended software product. It consists of following stages.

• Communication
  This is the first step between the user and the service provider. User and the service provider try to compromise.

• Requirement Gathering
  In this step, the team who is responsible for the project comes up with the requirements and classifies them. The practices below can be used to collect the requirements.

  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
  In this step, the team decides whether a software can satisfy the requirements of the user or not and the team shall be certain that there is no way for the software to be useless. Financially, practically and technologically feasibility for the organisation is the most important of this step.

• System Analysis
  In this step, the developers comes with the idea of best software model for the project.

• Software Design
  As its name implies, this is the software design step. Designs are in two different forms which are logical and physical.

• Coding
  This is the programming step. Implementation of the software design is done in proper programming language.

• Testing
  This phase consists of testing the software which is really important to handle errors before it’s too late.

• Integration
  In this stage software is integrated with outer world entities such as libraries, databases and other programs.

• Implementation
  At this stage, the software is installed on user machines and portability, adaptability, integration issues etc. is checked.

• Operation and Maintenance
  The software is checked according to efficiency and error free in this phase. Hidden bugs and real-world unidentified problems may appear here.

• Disposition
  This phase contains archiving data and required software components, closing down the system, planning disposition activity and terminating system at appropriate end-of-system time.

Software Development Paradigm

The software development paradigm consists of tools, methods, procedures and also defines SDLC to help developers to choose a strategy. Some of them are listed below.

• Waterfall Model
  In Waterfall model, stages are done one by one sequentially. When a step finishes, the other step starts and there is no turnaround. Therefore, every step should be finished without a potential issue which is perfect for developers who already designed similar software before.

• Iterative Model
  In this model, on every next iteration, more features and modules are designed, coded, tested and added to the software in other words, every cycle produces complete software but more comprehensive than the previous one.

• Spiral Model
  Spiral model is a combination of both, iterative model and one of the SDLC model.

• V – model
  In V-Model, software is tested at each stage before that stage finishes in other words in a reverse way which requires parallel verification and validation.

• Big Bang Model
  This model is the simplest model in its form which contains little planning, lots of programming and lots of funds. This model is better for learning and experimenting other than large projects.

References:
http://www.tutorialspoint.com/software_engineering/software_development_life_cycle.htm