Software development is a complex process that involves various stages, from conceptualizing the idea to delivering the final product to the customer. The Software Development Life Cycle (SDLC) is a framework that provides a systematic approach to the software development process.
The SDLC framework is widely used in the software industry to ensure that software is developed in a structured and methodical way. The process involves several stages, each with its own set of activities, deliverables, and goals.
In this blog, we will explore the concept of the Software Development Life Cycle in detail. We will discuss the different stages involved in the process, including requirements gathering, design, development, testing, deployment, and maintenance. We will also discuss the various models of SDLC, such as Waterfall, Agile, Spiral, Iterative, and V-model.
WHAT IS SDLC?
The Software Development Life Cycle is a structured process that enables the production of high-quality, low-cost software that meets and exceeds customer expectations and demands. The SDLC outlines a detailed plan with stages, that encompasses their own process and deliverables. SDLC is also referred to as Application Development Life Cycle.
Software development is a clumsy activity that requires proper identification of requirements, their implementations, and software deployment.
HOW WAS THE SDLC CREATED?
SDLC framework was developed in the 1950s and 1960s. The first implementations of software technologies involved simple tools like basic if/then statements and go-to lines. The concept of structured programming brought in the need for developing models and hence the SDLC was invented.
Before the 1950s, computing wasn’t elaborated to necessitate the use of a detailed approach like the SDLC. The concept of structured programs emerged with the growing complexity of programs, as it demanded more tactical model development.
ADVANTAGES OF IMPLEMENTING SDLC
- It provides a standardized framework that defines deliverables and activities
- It helps in project planning, estimating, and scheduling.
- Improves client relationships
- Decreases project risks, project management expenses, and overall cost of production.
- Increase the speed of development
- It makes project tracking and control easier
- Increases visibility on all aspects of the SDLC to all stakeholders involved in the development process.
STAGES OF SDLC
- Requirement analysis is the first stage in the SDLC process. During this phase, the development team collects input from all the stakeholders involved in the project. This input is further synthesized into detailed documentation of the requirements for creating the desired software. The deliverables produced from this phase include procurement needs, estimated costs, project plans, and schedules
- The feasibility study is conducted with the help of the Software Requirement Specification[SRS} document, which includes everything which should be designed and developed during the project life cycle. There are mainly five types of feasibility checks namely Economic, Legal, Operation feasibility, Technical, and Schedule
- Design – The system and software design documents are prepared as per the SRS document that defines the overall system architecture. There are two different kinds of design documents are developed in this phase namely High-Level Design and Low-Level Design
- Coding is done after the completion of the design phase. This is the longest phase of SLDC where the task is divided into multiple modules and is assigned to the various developers. In this phase, developers must follow certain predefined coding guidelines. The team must also use programming tools like compilers, interpreters, and debuggers to generate and implement the code.
- Testing Once the development is completed, the software is deployed to the testing environment. During this phase, QA and testing team tests the entire functionality of the application and may find some defects/bugs. The development team fixes the bugs and sends them back to QA for a re-test. This process continues till the software is bug-free, stable, and working according to the customer’s requirements.
- Deployment In this phase various elements of the software are pushed for the final deployment into the production environment. Based on the feedback given by the project manager, the final software is released
- Maintenance In this phase, various elements of the software are monitored. This may include the overall system performance, new security vulnerabilities, user experience, and analysis of bugs or errors in the system.
WHAT ARE SDLC METHODOLOGIES
The waterfall is the oldest, simplest, and most structured methodology. It is also referred to as the linear-sequential life cycle model. In this model, any phase in the development process begins only if the previous phase is completed and the phases do not overlap.
- Simple and easy to understand and use.
- Easy to manage as each phase has specific deliverables and review process
- It allows managerial and departmentalization control
- Difficult to implement in a complex project
- The waterfall model doesn’t allow going back once the stage is completed.
- As the testing stage comes late, it is very challenging to determine the problems uncovered at the early stages
Agile methodology is a practice that promotes continuous iteration of development and testing during the SDLC process. This methodology helps to identify and correct small issues in the project before they evolve into more significant problems. Developers can engage business stakeholders and take their feedback throughout the development process
- Improved customer engagement
- Increased productivity and visibility
- Manage changes more effectively
- Lack of emphasis on designing and documentation
- The project can be taken off easily if the customer representative is not clear about the final outcome
- It is difficult to assess the effort required at the beginning of SDLC
The V-model is also known as the verification and validation model as verifications and validation phases run in parallel. The development of each phase is associated with the testing phase and the next phase starts only after completion of the previous phase. i.e. for each development phase, there is a testing phase corresponding to it
- Simple and easy to use
- Proactive defect tracking
- Prevents the downward flow of the defects
- Rigid and least flexible
- No early prototypes for the software are produced.
- If any changes are to be made in development then all the testing documents must be updated irrespective of SRS docs.
Iterative development is the process of breaking down the development of a large application into smaller chunks. Each development cycle produces an incomplete but deployable version of the software. With each iteration, additional features can be designed, developed, and tested until the fully functional application is deployed to the customers.
- Easy testing and debugging
- More flexible and generates working software quickly
- Easy to manage risk as they can be identified and handled during their iteration
- System architecture-related problems may arise as all the requirements are not gathered for the entire software life cycle
The Spiral methodology combines iterative development with the systematically controlled aspects of the waterfall model. This methodology is a combination of sequential linear development and iterative development process i.e. the waterfall model with a high emphasis on risk analysis. It allows incremental refinement through each iteration around the spiral.
- Development is faster and additional features can be added in a systematic way
- Continuous development helps in risk management
- There is always a space for customer feedback
- Cost estimation becomes easier with smaller fragmentation of prototypes
- Larger documentation needs to be maintained as it has intermediate phases
- The spiral model protocol needs to be followed strictly for smooth operations
- Not advisable for smaller projects, as it might cost them more
The best practices to implement into your SDLC for greater chances for success are:
- Standard code quality
- Effective collaborations and streamlined workflows
- cross involvement of teams throughout the life cycle
Certain pitfalls can negatively impact an SDLC implementation. The most problematic phase is the failure to adequately implement the customer and stakeholders’ needs in the process. This may result in a misunderstanding of system requirements and inevitable disappointment with the results.
The complexity of the SDLC often causes the project to lose sight of specific requirements. Without strict compliance with all aspects of the parameters and design plans, a project can easily miss the mark.
THE FUTURE OF SDLC
Organizations are moving away from the older SDLC models, with the adoption of the fastest and latest development life cycles. Automation plays a significant role as the demand for speed and agility is increasing in the development process.
Development and operations are combining into DevOps capability, as the borderline between teams has been slowly dissolving in favor of a synchronized and streamlined approach to development.
The advanced approaches to SDLC have emerged as DevOps, the combination of practices and philosophies increases an ability of an organization to deliver applications faster. Security is no longer a separate step in the SDLC as it is viewed as a critical component throughout the SDLC.
In order to assure the success of the modern SDLC, an organization must be strategic in selecting tools that support and enhance this effort.