8 Basic SDLC Methodologies and How to Choose the Best One?

When it comes to developing a software application, there are specific steps that the development team follows. Collectively these are known as the software development life cycle (SDLC) and even if you didn’t choose one, your organization has some sort of methodology in place.

Understanding the basics for the different methodologies is helpful to determine what your organization is using today. For example, some firms use DevOps tools with a waterfall process and believe they are “doing DevOps”. By stepping out of the hall of mirrors and performing a realistic self-assessment, you can productively move forward toward the model that makes most sense for your organization.

 

What Are SDLC Methodologies 

Bringing an application or software to life requires the successful use of a SDLC methodology. Specifically, you must understand the essential steps that engineers undertake to ensure that the final product – the software – comes to life. 

As a general rule of software development, there are six steps that the DevOps teams are expected to follow. For starters, the team embarks on requirement analysis which is then followed by UI/UX design. After that, the team will embark on software development, after which testing and quality assurance will ensue. As the fifth step, the team will deploy the final code and finally consistently tweak it as part of ongoing maintenance. 

Notably, while all software developers will follow these steps, the way in which they implement the functions within each stage differs. This becomes the tenet of what we refer to as SDLC methodologies. Each of the methodologies will use a different hierarchical setup throughout the development process.  

 

Types of SDLC Models 

Broadly, SDLC models can be grouped into two. Specifically, there are evolutionary and sequential models, which are then divided into formal and informal models. While the sequential, formal models are easier to implement and manage, the evolutionary models are considered more flexible. The specific SDLC model types include: 

 

Agile Model 

The Agile SDLC model involves the customer at every development iteration, and as such, it is a practical methodology for projects in which the customer is not sure of what deliverables they want. With the Agile methodology, the project is divided into short sub-projects, which provides flexibility for the entire project. Consequently, the team should be able to roll out a fast release of the first product version. 

On the downside, it’s difficult to track the project costs because of the constant shifts and changes in direction. Additionally, getting a team that is able to take on the new requirements when they conflict with the architecture already in place can create a mess. Still, when the customer needs constant changes after only having the initial plan, the Agile model comes in handy for flexibility. 

 

Lean Model 

The Lean model is a preferred approach when working on a project that provides the best possible optimization of time and resources. With a well-considered approach, the team is able to provide a minimum viable product, which can then be iterated based on the feedback obtained from the different parties. 

The model requires that the team takes on a streamlined approach, thus ensuring that more functionalities are delivered within the shortest time possible. Unnecessary activities are eliminated, which then reduces the cost. The downside, though, is that this methodology can be difficult to scale because it requires strict documentation and, as such, is very dependent on the team involved. 

 

Waterfall Model 

The Waterfall model follows the stated development stages in the specified order: Analysis, Design, Coding, Testing, Deployment, and Maintenance, without skipping any steps. At each step, there will be expected project deliverables that are meant to be meticulously documented. 

Because the steps are followed one at a time without being rushed, this model is best for small and medium-sized projects. So, (1) if the project requires tight controls, (2) uses well-known technology stacks, and (3) adheres to specific development rules, in order, the Waterfall model can work well. 

 

Iterative Model 

Also referred to as the Incremental model, this one divides the development steps within the SDLC into multiple iterations. The dev team adds new software modules as they progress through the development cycle – without necessarily affecting the previously added modules. 

Note that with this type of development, the product itself changes with each iteration. It would be a fallacy to think that the software changes as the design basically remains consistent. If you are working on a large-scale, rather lengthy project, this model can be helpful. For example, if you are working on a project like micro services that requires fast delivery of basic functionalities, the iterative model offers the flexibility to distribute the project in parts. 

 

Spiral Model 

At times, your engineers will embark on a project that is considered significant and complex with unclear business needs. During such projects, the spiral model comes in handy because it requires the team to focus on completing a comprehensive risk assessment. For this model to work, you will be looking to engage with the different parties involved in the project. 

If you are considering this model, it would be prudent to keep in mind that the Spiral model lasts a minimum of six months. The first stages within these six months will include comprehensive planning, risk analysis, project prototyping, and a review of the previously delivered parts. As these parts of the project will often take a spiral pattern, the project will likely end up having an extended timeframe. 

 

DevOps 

The DevOps methodology is one that seeks to bring the dev teams and the information technology operatives together. The heart of this model encourages a culture of collaboration, especially in an environment where IT and dev teams exist in separate silos. This model was evolved in direct response to the loopholes available within the Waterfall and Agile models. 

To be good at the DevOps model, you will need a team that is interested in deployment and network operation, scripting and coding, and testing and deployment. Altogether, the DevOps methodology is an interplay between operations, quality assurance, and development. The underlying principles are automation, iteration, continuous improvement, and collaboration. 

A project that needs continuous integration, deployment, and automation can definitely benefit from the DevOps methodology. Making the change requires a significant cultural shift, which can be difficult, because the different departments need to collaborate effectively. If you’re looking for a high ROI, increased efficiency, and early detection of any problems within the code or the architecture, then a mature DevOps culture is for you.

 

V-shaped Model 

Also known as the Validation and Verification Model, this one is a linear methodology that requires  corresponding tests for each of the stages. The model is best for development environments in which there is a need for excellent quality control. While it is relatively expensive and time-consuming, the model makes it easy to identify any code and architectural errors early on within the development cycle. If you are working on a project that cannot afford any errors or downtime, like flight management software or software for medical devices, the V-shaped model can be helpful. 

 

Prototyping Model 

The Prototyping model is considered outdated, having been mostly used as an early alternative to Waterfall in the mid-1970s. As inferred within the name, the methodology requires that a prototype be first built, tested, and consequently reworked to develop the best possible outcome. The model has three arms that are intertwined. Specifically, customer feedback, prototype testing, and prototype development all work in conjunction to ensure that the customer gets a product as fast as possible. 

This prototyping model has four distinct categories, including (1) rapid throwaway prototyping, in which the developed prototype does not necessarily need to be part of the development, (2) evolutionary prototyping, whereby the prototype that was initially developed is incrementally refined based on the feedback given, (3) and incremental prototyping, in which the final expected product is broken down into different pieces which are then individually developed. 

While it might have been phased out, the Prototyping model means that the customer gets to have a glimpse at a partial product earlier on during the product life cycle. Additionally, it works best for products that already have an existing prototype, but need additional functionality.  

 

Big Bang Model

An extra SDLC model is the Big Bang model. This one is considered relatively straightforward and works best for projects that do not have a solid initial plan. Additionally, it works well for a project with a bigger pool of funds and no time constraints. Here, the project requirements are implemented as they arrive, which will then be integrated and tested at the end of each module. 

Choosing the Best SDLC Model 

Finding the best SDLC model isn’t always easy, you want first to consider the requirements, budget, business needs, and the specified timeline for the project. Each of these methodologies offers different value propositions and degrees of flexibility, and finding the right way for your development cycle requires careful consideration.

In addition, different industries with regulatory requirements may feel that newer models like Agile and DevOps aren’t feasible for their software products, or that a combination of different models makes the most sense. Either way, it’s important to be realistic about what model to use so that expectations can be set for all different stakeholders involved.

Guide-Rails_® offers your team a one-of-a-kind platform for software development. Our Value Stream Delivery platform can successfully remove complexities that come with software development and automate the end-to-end process no matter what SDLC methodology you use. The result is that your developers have more time to focus on the code without being distracted by infrastructure and administrative tasks. Reach out today and learn more about how Guide-Rails_® can save you time, frustration, and money.