Unit 5 Activity 2: System Development Life Cycle (SDLC)

Definition - What does Software Development Life Cycle (SDLC)  mean?

The software development life cycle (SDLC) is a framework defining tasks performed at each step in the software development process. SDLC is a structure followed by a development team within the software organization. It consists of a detailed plan describing how to develop, maintain and replace specific software. The life cycle defines a methodology for improving the quality of software and the overall development process.

This term is also known as the software development process.

Why is software development life cycle important?

SDLC serves as a guide to the project and provides a flexible and consistent medium to accommodate changes, and perform the project to meet client’s objectives. SDLC phases define key schedule and delivery points which ensure timely and correct delivery to the client within budget and other constraints and project requirements.

SDLC co-operates project control and management activities as they must be introduced within each phase of SDLC.

SDLC consists of following activities:

1.Planning: The most important parts of software development, requirement gathering or requirement analysis are usually done by the most skilled and experienced software engineers in the organization. After the requirements are gathered from the client, a scope document is created in which the scope of the project is determined and documented.

2.Implementation: The software engineers start writing the code according to the client's requirements.

3.Testing: This is the process of finding defects or bugs in the created software.

4.Documentation: Every step in the project is documented for future reference and for the improvement of the software in the development process. The design documentation may include writing the application programming interface (API).

5.Deployment and maintenance: The software is deployed after it has been approved for release.

6.Maintaining: Software maintenance is done for future reference. Software improvement and new requirements (change requests) can take longer than the time needed to create the initial development of the software.

Can you provide examples of how SDLC can be used?

An SDLC model defines implementation of an approach to the project. It defines the various processes, and phases that would be carried out throughout the project to produce the desired output. There are a variety of SDLC models that exist catering to different needs and characteristics of a project. Some are of iterative nature (Prototyping), whereas some are sequential (waterfall). Some of the well known SDLC models are:

There are several software development models followed by various organizations:

1.Waterfall Model: This model involves finishing the first phase completely before commencing the next one. When each phase is completed successfully, it is reviewed to see if the project is on track and whether it is feasible to continue.

2.V-Shaped Model: This model focuses on execution of processes in a sequential manner, similar to the waterfall model but with more importance placed on testing. Testing procedures are written even before the commencement of writing code. A system plan is generated before starting the development phase.

3.Incremental Model: This life cycle model involves multiple development cycles. The cycles are divided up into smaller iterations. These iterations can be easily managed and go through a set of phases including requirements, design, implementation and testing. A working version of the software is produced during the first iteration, so working software is created early in the development process.