What is the Software Development Life Cycle?
The software development life cycle (SDLC) is a process used for structuring the development of any software system, from initiation through to implementation. An increase in demand for software to meet customer needs effectively but with less cost and faster delivery has put tremendous pressure on modern organizations. To stay competitive, companies must build their software correctly and transform their businesses by following efficient software engineering methodologies, practices, and concepts. Without meeting these changes, there can be a drop in productivity, leading ultimately to business failure. Customer interaction at all levels with the right methodology for implementing the software is crucial to any organization’s success.
Why use the Software Development Life Cycle?
SDLC is considered the foundation for all software development methodologies, with various activities associated with each level. Activities such as budgets, requirements gathering, and documentation writing are part of the cycle, with the more technical elements. SDLC usually begins with determining customer business needs, followed by implementation and testing. The cycle ends with the fulfillment of all requirements. The software development life cycle comprises of seven distinct phases:
Phase 1: Planning
The planning phase will determine project goals and establish a high-level plan for the intended project. Planning is, by definition, a fundamental and critical organizational phase. The three primary activities involved in the planning phase are as follows:
- Identification of the system for development
- Feasibility assessment
- Creation of project plan
Phase 2: Analysis
End-user business requirement analysis takes place during this phase. Project goals are converted into the defined system functions that the organization intends to develop. The three primary activities involved in the analysis phase are as follows:
- Gathering business requirement
- Creating process diagrams
- Performing a detailed analysis
Business requirement gathering is the most crucial part at this level of SDLC. Business requirements are a brief set of business functionalities that the system needs to meet to be successful. This phase does not define technical details such as the type of technology implemented in the system. A sample business requirement might look like “The system must track all the employees by their respective department, region, and the designation.” This requirement shows no such detail as to how the system will implement this requirement, but rather what the system must do concerning the business.
Phase 3: Design
In the design phase, we describe the desired features and operations of the system. This phase includes business rules, pseudo-code, screen layouts, and other necessary documentation. The two primary activities involved in the design phase are as follows:
- Designing the IT infrastructure
- Designing the system model
The IT infrastructure should have solid foundations to avoid any crash, malfunction, or reduction in performance. In this phase, the specialist recommends the clients and servers required on a cost and time basis and the system’s technical feasibility. The organization also creates user interaction interfaces, data models, and entity relationship diagrams (ERDs) in this phase.
Phase 4: Development
The development phase is when all documents from the previous step transfer into the system. The primary activities involved in the development phase are as follows:
- Development of IT infrastructure
- Development of database and code
During the design phase, just the IT infrastructure blueprint is provided. In contrast, the organization purchases and installs the respective software and hardware to support the IT infrastructure during the development phase. Following this, creating the database and actual code can begin to complete the system according to the specifications.
Phase 5: Testing
All pieces of code are integrated during the testing phase and deployed in the testing environment. Testers then work through Software Testing Life Cycle activities to check the system for errors, bugs, and defects to verify the system’s functionalities work as expected. The two primary activities involved in the testing phase are as follows:
- Writing test cases
- Execution of test cases
Testing is a critical part of the software development life cycle. To provide quality software, an organization must systematically perform testing. After writing test cases, the tester executes them. They compare the expected result with an actual result to verify the system and ensure it operates correctly. Writing test cases and manually performing them is an intensive task for any organization but will succeed if executed properly.
Phase 6: Deployment
During this next phase, the system is deployed to a real-life (the client’s) environment where actual users can begin operating the system. All data and components are present in the production environment. This phase is also called ‘delivery.’
Phase 7: Maintenance
Any necessary enhancements, corrections, and changes are made during the maintenance phase to ensure the system continues to work and remain updated to meet business goals. It is necessary to maintain and upgrade the system from time to time to adapt to future needs. The three primary activities involved in the maintenance phase are as follows:
- Support the system users
- System maintenance
- System changes and adjustment
The Importance of SDLC
SDLC gives structure to the several phases involved in software development efforts and does not conclude until fulfilling all requirements and potential needs. The main advantage of using software development life cycle is the control it provides for the development process. It helps to ensure the system complies with all specified requirements. However, there are some disadvantages to using SDLC. It does not work so well where there are levels of uncertainty or unnecessary overheads. It directs the development efforts with an emphasis on planning but does not encourage creative input or innovation in the lifecycle. For those reasons, many organizations tend to adopt Agile and other such incremental rather than sequential methodologies.