What is Software Development Life Cycle Model?
Software development life cycle (SDLC) refers to processes used to create software. SDLC outlines detailed stages so that software can be created quickly. It outlines the phases involved in developing a product. Plans, creation, testing, and deployment are included in the SDLC phases. As part of the SDLC, the end product is ensured that it meets the quality requirements.Â
Here are the 5 best Software Development Processes (and how to choose the right one for you)
Developing software requires a series of stages to achieve the desired result. Applications are developed according to models which guide developers. For a correct implementation, different models are required. We have listed a few SDLC models that you can use when developing an application.
Below are Software Development Life Cycle Model Processes
1. Waterfall
What it is:
Software development using the waterfall model is an old, traditional method of developing software (also known as the “linear sequential model” or “Classic lifecycle model”). If you think about the Waterfall method in its simplest form, you can imagine that each step of the SDLC is followed sequentially-you must finish each one before moving on. The phases overlap slightly during most practical applications, with feedback and information flowing between them.
This is sometimes called a “plan-driven” method since you must first know everything that has to be done to finish a job. The waterfall is a term used to describe the flow of each segment into the next.
Phases:
- Plan
- Prerequisites
- Design of systems and software
- integration
- Testing
- Deployment
- Support/Updates
Who needs it: Team members who need documentation and rigid structures.
The Waterfall software development process has rigid boundaries and extensive planning requirements, as a result of which it works best when your objectives, requirements, and technological stack are unlikely to undergo radical changes throughout the development process (such as during shorter one-off projects).
In terms of practicality, the Waterfall process is best suited for larger organizations with many stakeholders involved (e.g., government agencies) and many requirements and scope documents to be signed off on before a project can start.
2. Agile and Scrum
What it is:
Software development is an iterative and dynamic process that follows the Agile method (and Scrum as its most popular methodology).
An Agile process does not follow a rigid, sequential flow, but rather cross-functional teams can develop usable software after 2 weeks to 2 months of effort by using a fast-paced, rapid development style known as “Sprints.”
The Agile construction method consists of moving fast, releasing often, and responding to user needs, even if they don’t align with your original plans. That means that you don’t require a detailed statement of work or a complete set of requirements before you start the work. By following a specific strategy, you maintain your focus on moving forward in a particular direction but are aware that you may change your path along the way.
It explains a lot more about Agile than this in the Guide to implementing Agile and Scrum. As an example of what it might look like in practice, we have provided a simple example. Take the case of adding X, Y, and Z features to one of your products. The idea of an Agile Sprint is to create a bare minimum that is useful and usable (rather than building everything over months) and then releases it to your customers.
You can react quickly to customer needs throughout the software development process by creating tighter feedback loops.
Phases:
- Backlog of products
- Sprint backlog
- Sprint (Design & Development)
- Complete the software release
- Feedback and validation (add to backlog)
- Plan the next sprint
Who it’s for:
Dynamic teams that update products continuously.
Agile is favored by startups and technology companies due to its dynamic and user-centric nature, especially for continuously testing new products or updating long-standing ones.
In the long run, Agile allows organizations to move faster and test their theories without risking their entire livelihood on a significant release that their users hate as it becomes easier to do minor releases and gather user feedback. Furthermore, as testing usually occurs after each small iteration of the product, it is much easier to track down bugs or revert to an earlier version of the product if something more serious goes wrong.
3. Incremental and Iterative
What it is:
Several software development methods are incremental and iterative. They can meet both the requirements of software development processes that have a structure and ahead of time planning and the flexibility of agile methods.
In both these processes, software is created in small bits and exposed to users for feedback; however, there is a difference between what is made during each release.Â
Each time an incremental software development process is used for the product development process, the product adds a simple form of an entirely new function or feature to the product. For example, you could create an overall plan, build an MVP with only the core functionality, and then add more functionality based on feedback received.Â
On the other hand, iterative software development processes allow you to release versions of all the features you’re planning on releasing with every version. For example, if you were to create a version 0.1 with the simplest version of each segment and then upgrade it across the board in v0.2, v0.3, etc., that would be a way to look at it.
The incremental phases are:
- Planned Increment
- Specs
- Development
- Validation
- Repeat for each version
Phases of iteration:
- Analysis
- Design
- Development
- Testing (Repeat these until you’re ready to release)
Who it’s for:
The Waterfall method does not provide flexibility to teams with clear requirements.
These two methods are ideal for large projects with well-defined scopes (or teams with a low-risk tolerance) since they add flexibility to your software development process without throwing a plan to the wind.
Using the incremental approach, you can receive feedback immediately on your feature, allowing you to validate your business case immediately. While iterating enables you to get a clearer picture of the complete product, your feedback will be more effective.
It is more efficient, cost-effective, and time-saving to establish user needs early in the development process than wait until the end.
4. V-Shaped
What it is:
As an evolution of the traditional Waterfall methodology, V-shaped software development makes up for its biggest flaw: A lack of testing.
Each step of the V-shaped development process is followed by a strict “validation and verification” phase, where requirements are tested before proceeding. This prevents the testing from being done sequentially and saves it for the end.
Phases:
- Prerequisites
- Specs
- Detailed design
- Low-level design
- Developing
- Unit testing
- Integration testing
- System testing
- Acceptance testing
Who it’s for:
Projects with a small scope handled by smaller teams.
If you’ve got a small project with relatively straightforward requirements and a pretty static scope, you may want to use the V-shaped software development process. This allows ample opportunity to test along the way rather than following a plan and discovering issues at the end.
5. Spiral
 What it is:
The spiral software development process combines the incremental nature of Iterative, Incremental, and Agile, focusing on testing and risk assessment of V-shaped development.
The next step is to conduct a comprehensive risk assessment to identify errors or areas of excessive risk after the plan has been prepared for a specific iteration or milestone. Imagine, for instance, that as part of your plan, you will implement a feature that any of your customers has not validated. It is often better to build a prototype and test with users before going into the fully developed stage rather than simply adding it to your current milestone. As each milestone is completed, the scope is expanded further by the overall project (like a spiral) and you begin to plan your strategy and re-evaluate the project risks.
Phases:
- A plan
- assessing risk
- Development and validation
- Evaluating results and planning next steps
Who it’s for:
Team members working on large projects which are risk-averse.
Processes like this are inherently aimed at reducing risk. This approach is particularly useful for people working on large or critical projects that require high levels of documentation and validation along the way, as it offers a great deal of documentation and validation. Having the product delivered in this manner is also beneficial if a customer has a vague idea of what he or she needs and expects major changes during the development of the product.
Processes and plans are just guesses
The path in front of you can seem endless when you’re developing a new piece of software from scratch. You should not be overwhelmed by all of the options available. Keep these four principles in mind:
- Understand it: Know why you want to build what you want.
- Create working software: Design and implement your idea.
- Test it: Get feedback from users.
- Iterate: Use the feedback to improve it.
Picking the right development process for your project is also the same as picking the right development tool. Learn everything that you can about the steps of the SDLC, then choose the method that feels comfortable to you and your team, test it out, and gain feedback from them.
Keep in mind that it is a Software Development Life Cycle Model. If you have trouble getting it right the first time, understand why it didn’t work before picking up a new method and starting all over again.
