Different Methodologies of SDLC (TOP 8)

What is the SDLC?

Before we jump into the main topic which is ‘Different Methodologies of SDLC’, let’s learn what is SDLC. If you think that software development life cycle (SDLC) is just a fancier name for the work that developers do, then you are in for a little bit of history. SDLC is a methodology utilised in the software industry for the purpose of designing, developing, and testing high-quality software. The objective of the software development life cycle (SDLC) is to produce high-quality software that not only satisfies but also exceeds the requirements set forth by the customer, all while remaining on schedule and under budget. Even when computers took up an entire room, nobody was complaining about the software development life cycle (SDLC), even though software development has been around for a very long time. In response to an increase in the number of available business opportunities, software companies began to expand their product lines in the 1960s. The leaders of the project and the developers working on it quickly came to the conclusion that a flawed workflow or process was more likely to bring down the undertaking than ineffective coding skills. The model software development life cycle emerged as a result of this process and eventually became widely used. Everyone would probably agree that it is extremely important to have orderly control over every stage of the planning and delivery of the software project. Your product development team can handle everything while floating in the air and still have plenty of brainpower left over. The software development life cycle (SDLC) thrives in an environment that is cluttered with interdepartmental meddling, consistent client demands, and multiple developers. Anyone is given the ability to monitor the direction the software is taking and make adjustments as necessary. These methods contribute to the development of software that has the highest possible quality while also having the lowest possible cost and the shortest possible development time. It makes an effort to match the requirements of the customers with a detailed structure and set of specifications, which enables developers to successfully plan, build, and develop software.

Key Phases of Model SDLC

SDLC is a model that specifies the actions that must be taken at each stage of the software development process. It includes a detailed plan for the creation, implementation, and upkeep of software. Building effective software involves several essential steps, including analysis, planning, design, testing, and finally deployment of the finished product. The requirements of the end users must be determined, resources must be gathered, a schedule must be established, and the creation of software requires significant group effort. The following is a list of the fundamental stages that are involved in the software development life cycle that everyone, more or less, goes through:

• Analyze Customer Needs

The first step, which is analysing the needs of your customers, should come as no surprise. During this stage, the focus is on compiling information from a variety of sources and planning the process in accordance with that information. It begins with determining what it is that customers want, then moves on to conducting an analysis of the resources required to meet those needs, and finally moves on to cost planning in order to successfully and affordably maintain the development process.

• Outline a Plan

Up until this point in the SDLC processes, all we are aware of are the requirements. Before we move forward with the structure of the project, we must first plan the resources, costs, and other minute details of the endeavour. The limit of the cost is something that needs careful planning, despite the fact that the resources are manageable. Your product’s development team needs to ensure that it strikes a healthy balance between all of the competing priorities.

• Prepare a Design

The planning stage comes after that. You are required to create a design in order to define the overall framework, and this is specified in the requirements and the detailed plan for the project. During the designing stage, everything is considered, including the name of the project, its description, its functionality, as well as the identification of its key elements and any technical gaps. Low-level design (LLD) and high-level design (HLD) are the two primary categories that make up the design process (HLD).

• Start Coding

This is one of the phases in the software development life cycle that takes up the most time and effort. At this point, the developers take on the role of the protagonist and begin doing what they do most effectively. They write the software code by adhering to pre-defined guidelines for code quality and coding standards, as well as by using the necessary programming tools. Ultimately, they implement these guidelines.

• Test the Progress

After the coding portion of the project has been finished, the testing of the system’s functionality can begin. During this phase, we are going to test to see whether or not the software as a whole is functioning as expected. Another reason for it is to check for any errors or problems with the technical side of things, should there be any.

• Begin Deployment

This is the moment that everyone has been looking forward to. If the software developers do not find any problems during the testing phase, they will move on to the next phase, which is the rollout phase. Keep in mind that it is equally important to make certain that the feedback-informed deployment process goes off without a hitch, as this will prevent any problems from arising.

• Continue with Maintenance

Once the software has been deployed, the next stage of the software development life cycle models is for customers to begin using the product. At this point, it is time to begin observing other aspects. They consist of timely updates, immediate bug fixes, and the most recent features that have been added. This phase is just as important as the first one was in order to ensure that the software continues to perform its functions correctly and efficiently.

Methodology of Software Development Life Cycle: Important Models and Approaches

Methodologies of the SDLC are the strategies, procedures, and practises that software development teams implement in order to successfully navigate the Software Development Life Cycle (SDLC). Now that you have a fundamental understanding of the phases of the software development life cycle (SDLC), you can impress your friends who aren’t developers by demonstrating that you know about popular SDLC methodologies and what they bring to the table.

1. Agile Software Development Life Cycle 

Agile SDLC is one of the SDLC methodologies that is crucial to take note. In spite of the fact that the Agile model has been around for close to twenty years at this point, the last five to ten years have seen its most significant growth. Because of its widespread acceptance, the Agile methodology is even being applied by some companies to projects that have nothing to do with software development. The incremental and iterative approach forms the foundation of the agile methodology. Fast failure is a notable aspect of it, and Agile features ongoing release cycles. Each of these is an improvement over the previous release in that it incorporates a few minor changes, and the product is tested after each iteration. The Agile methodology can be implemented in a manner known as a Scrum, which is designed to assist development teams in structuring difficult project requirements. Scrum teams organise their work into “sprints,” which are periods that range in length from 2 to 4 weeks and are designed to facilitate the completion of tasks. Daily Scrum meetings are held in order to assist the entire team in keeping track of the progress that has been made up until that point. The individual who is in charge of the Scrum team is referred to as the ScrumMaster. They are responsible, as is customary, for ensuring that the team stays on track to achieve the objective.

Agile Pros:

• able to adapt to new changes or improvements made during the development phase without being constrained by a budget
• engages business stakeholders and project managers, and regularly solicits their input throughout the software development process.
• Rapid development and testing make it possible to identify any gaps in the requirements or employed technologies. Finding alternatives is made simple because of this.
• assists development teams in locating and resolving minor issues before they become serious
• saves a lot of money and time because there is less documentation.

Agile Cons:

• It is incredibly difficult to estimate the total effort needed at the very beginning of large, complex projects.
• When customers or end users are unsure of the requirements, the risk is high.
• needs valuable resources
• minimises the importance of designing and documenting processes

2. DevOps Software Development Life Cycle

The DevOps methodology originated as a result of the convergence of two trends. First, the incorporation of Agile and Lean practises into the operations team’s workflow. Second, an industry-wide shift toward an increased awareness of the benefits of collaboration between development and operations staff throughout the entire software development life cycle (SDLC). Developers and operations are both referred to by the acronym DevOps. When a DevOps methodology is used, the development team and the operations team collaborate in order to expedite and innovate the deployment of highly reliable software products and to generate new ones as well. The DevOps model emphasises continuous feedback, process improvement, and discipline, as well as the automation of as many manual development processes as is practically possible. These are important highlights. The software that is currently being developed receives updates that are relatively minor but do so more frequently.

DevOps Pros:

• The amount of money and time needed to complete unforeseen tasks and fix bugs is greatly reduced.
• improves the employee loyalty rates
• Because the operations and development teams are simultaneously made aware of any potential roadblocks, the entire development process goes more quickly.
• faster rates of failure recovery
• Higher credibility

DevOps Cons:

• High risk of security problems, including spoofing and man-in-the-middle attacks, because the software development approach prioritises speed over security

3. Rapid Application Development (RAD)

Rapid Application Development works best for such projects when you have an original idea that demands total confidentiality and intends to enter the market as an initiator to capitalise on the first-mover advantage. When there isn’t time for in-depth planning, the software development life cycle methodology is used as an adaptive strategy.

Due to the high risks and costs involved in this process, the importance of software prototyping and the business benefits it offers cannot be overstated. The project is carried out by the developers not through planning but rather through the testing and adaptation of prototypes. Testing also plays an important role in this context because the changes to the project depend on it. You are able to launch the product with the features it requires at the time and based on the feedback from customers.

Things to Take Into Account:

• This methodology runs counter to the conventional approach to software development and necessitates a high level of specialised knowledge and adaptability on the part of the developers in order to successfully complete the project.
• You would require a relatively higher level of involvement from both your customers and your users.
• There will always be a lack of scalability because RAD lags behind in terms of long-term planning and requirements due to the fact that the project is either small or mid-sized and there is an urgency to reach the market.

4. Waterfall

The Waterfall methodology is a sequential and linear flow for the development of software applications; it is also known as the traditional methodology. The procedure can be broken down into a number of discrete steps, each of which must reach its conclusion before moving on to the following step in the sequence. The requirements, design, execution, testing, and release stages are completed in this order when using the Waterfall methodology.

Advantages of Waterfall:

It is well organised and simple to comprehend. The activities have been clearly outlined, which helps to foster careful planning for the project. In addition to this, there are predetermined deliverables at each and every stage of the process.

Drawbacks of Waterfall:

It is difficult and time-consuming to return to any previous stage once it has been completed. It has limited adaptability in response to shifting priorities and priorities. In comparison to other methods, not only is it more labor- and resource-intensive, but it also comes at a higher financial cost.

5. Prototyping

Through the use of this methodology, software application prototypes are crafted in order to simulate the operational facets of a desired final product. The primary purpose of prototyping is to visualise the components of a software solution and to compare those components to the requirements of the customer. There are many different kinds of prototyping, but the most common types are known as throwaway and evolutionary. Both throwaway prototyping and evolutionary prototyping refer to the process of creating a model that will eventually be thrown away, but evolutionary prototyping describes the creation of a robust prototype that will be continuously improved until it reaches its final version.

Advantages of Prototyping:

A fully operational version of the software solution can assist in the identification of potential risks and threats that can be addressed in a timely manner, thereby reducing the amount of money and time that is invested. In addition, the user is involved and has the ability to visualise a version of the software that is operational.

Drawbacks of Prototyping:

Confusion between the finished version of the system and the working prototype of the system is possible. The creation of a prototype can frequently cause developers to squander a considerable amount of time, which is time that could have been put to better use elsewhere. In addition to this, the implementation of functioning prototypes can be quite pricey. The tendency of client audiences to believe that a good-looking prototype indicates that the software is almost finished is yet another disadvantage of prototypes. In reality, however, this is not typically the case the majority of the time. Another disadvantage to take into consideration is the concurrent process of designing and developing software, which leads to numerous changes in the programming code at the very last minute.

6. Spiral Methodology

The identification of risks is the primary focus of the Spiral Model. The developer is responsible for identifying any potential risks and putting their solution into action. After some time, a prototype is developed to check for additional risks and validate risk coverage.

Advantages:

• This risk analysis limits the potential for risk to occur.
• The subsequent iteration can adjust to any requirement changes.
• The model works well for large projects where there are risks and changing requirements.

Disadvantages:

• Only large projects are best suited for the spiral model.
• The price may be high because it may take many iterations and a long time to get to the final product.

7. Scrum Development Methodology

Scrum is an agile software development framework that emphasises iterative and incremental software development. This approach is more time-constrained and meticulously planned out. It works particularly well for projects with unclear requirements and requirements that are subject to frequent and rapid change. Planning, meetings, and discussions are all components of the scrum process, as are reviews. The application of this methodology contributes to the accelerated development of the Project. The Scrum Master is responsible for organising Scrum and contributing to the team’s ability to meet its Sprint goals. In scrum, the term “backlog” refers to the prioritised list of tasks that need to be completed. Backlog items are typically finished in short “sprints” that last between two and four weeks. Every day, there is a meeting called a Scrum, and its purpose is to report on the progress of the backlogs and discuss any potential roadblocks.

Advantages:

• The team is in complete control of making decisions.
• The daily meeting enables the developer to gauge each team member’s productivity, which boosts overall output.

Disadvantages:

• Not appropriate for small projects.
• needs resources with extensive experience.

8. Feature-Driven Development

FDD adopts an incremental & iterative methodology to deliver working software. The function has a modest client value. For instance, “Validate the user’s password.” There are different features to the project.

FDD has 5 process Steps:

#1) Develop an Overall model: In this step, an overall model is created, which is essentially a merger of specific domain models. The customer is involved in the model development process along with the developer.

#2) Build a feature list: The features list is created in this step. The entire project is broken down into features. Similar to how user stories relate to scrum, features relate to FDD. Two weeks are required for the delivery of a feature.

#3) The plan by feature: After creating a feature list, the next step is to decide which features should be implemented first and who will be the feature’s owner. To do this, teams are chosen, and features that need to be implemented are assigned to them.

#4) Design by feature: In this step, features are designed. The two-week design period’s features are chosen by the chief programmer. For each feature, thorough sequence diagrams are created in collaboration with the feature owners. The class and method prologues are written next, and the design inspection comes after that.

#5) Build by feature: The class owner creates the class’s code after the design inspection is successful. Unit tests and inspections are performed on newly developed code. The code is developed with the chief programmer’s approval in order to enable the addition of the entire feature to man-made builds.

Advantages:

• FDD’s ability to scale up for large projects.
• It is a straightforward methodology that businesses can quickly adopt.

Disadvantages:

• For smaller projects, insufficient.
• The client receives no written documentation.

8. V model

Verification and Validation Model are both referred to as the V Model. Although it was inspired by the Waterfall model, which performs testing at the end of the project, it differs from the Waterfall model in that it incorporates testing at each stage of the development process. In a manner analogous to that of the Waterfall model, the V model does not progress to the next stage until the one that came before it has been finished.

Pros:

• the capacity to stop the spread of defects
• An excellent match for small projects with clearly defined requirements
• greater likelihood of success
• provides comfort and simplicity.
• proactive monitoring of possible flaws
• saves a lot of time because testing-related planning and design are completed before any actual coding is done.

Cons:

• Rigidity even greater than in the Waterfall model
• Because the software is developed during the implementation phase, early prototype creation is not possible.
• If changes are made throughout the development process, requirement and test documents must be updated.

Conclusion

The requirements of a project and the nature of the project will determine which SDLC methodologies will be used for the project. Not every methodology is going to be appropriate for the project you’re working on. One of the most important decisions that must be made for a project is choosing the appropriate methodology.

References

9 SDLC Methodologies: Understand and Choose the Best SDLC Methodology for Your Project. (2019, March 17). Radixweb. Retrieved January 17, 2023, from https:///blog/best-software-development-life-cycle-methodologies-in-2019

Top 7 SDLC Methodologies: Phases, Models and Advantages. (2022, March 1). Hackr.io. Retrieved January 17, 2023, from https://hackr.io/blog/sdlc-methodologies

SDLC Methodologies | SDLC Phases, Models and Advantages. (2019, January 4). SDLC Methodologies | SDLC Phases, Models and Advantages. Retrieved January 17, 2023, from https://svitla.com/blog/sdlc-methodologies

Top SDLC methodologies [software development methodologies]. Software Testing Help. (2022, December 5). Retrieved January 17, 2023, from https://www.softwaretestinghelp.com/sdlc-methodologies/