Just like anything that goes through a process of growth, development, and change, software development has definable life cycle stages. The Software Development Life Cycle (SDLC) describes the phases of software development and the order they progress. Each aspect results in deliverables which creates the basis to move onto the next step. Here we look at the six phases that are included in every software development life cycle.
1. Requirement Gathering and Analysis
In the first stage of the software development life cycle, project managers and stakeholders gather and analyze the business requirements for the software. This involves asking questions like who will use the system, how will it be used, and what the data inputs and outputs will be. These questions help to clarify the requirements for which we analyze them for their validity and incorporation into the project. A Requirement Specification Document is the final outcome that directs the next phase of the project.
The requirements information then addresses software and system design which ultimately defines the overall system architecture. It also informs the hardware and system requirements that will be needed for the next phase and allows testers to develop the test strategy where they will determine what and how to test the software.
3. Implementation or Coding
Once the system design is received the work on coding can begin. The coding is usually broken up into modules or units to make the task more manageable and to ensure the completion of each component before moving on. Because this stage is where the coding happens, it’s the central area of focus for the developer and is usually the longest phase. This step doesn’t mean that the other stages are any less important – consistency and quality is essential throughout the entire software development life cycle.
In the testing phase, the development of the software code needs to be measured up against the requirements specified in the first phase of the lifecycle. This requirement helps to ascertain that the software is addressing the needs and goals of the client. Functional testing processes such as unit testing, integration testing, system testing, acceptance testing, and non-functional testing are completed.
Once testing is completed and confirmed that the new software meets all requirements and doesn’t have any bugs, it’s time to deploy the new software to the client or user.
Users conduct the first beta testing, and as they explore all functionalities of the software, they may discover some previously undiscovered bugs or issues. The software engineering department can then correct those bugs and proceed towards final deployment of the software.
Software delivery is not the end of the development lifecycle! Issues with developed software arise from time to time as customers start using the software. This means that the software will need ongoing maintenance, so the development team needs to continue to monitor and update the system as required.
The Software Development Life Cycle is a useful framework so we can understand the process of software development and ensure developed software meets goals and requirements and ultimately results in a high-quality system.