Software Development Life Cycle Methodologies

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What is SDLC?

Software  development is the bread and butter of software engineers and  developers all around. Every day, software engineers and professionals  alike have to immerse themselves into the dynamics of the best Software Development Lifecycle (SDLC) methodology and approach to develop and deliver software in optimum conditions. But, what is SDLC?

In  the simplest terms, SDLC methodologies provide a systematic framework  to design, develop and deliver software applications, from beginning to  end. It is a series of steps that offer a foundation for the software  development process. Having a structure to develop software is  fundamental, which is why there are multiple software development  methodologies available to choose from. It is increasingly important for  software engineers to select the right SDLC model that meets specific  requirements and concerns of the project to drive success. In this  article, we go into the details of SDLC methodologies, their relevance,  their advantages, disadvantages, and everything in between.

To a  certain extent, SDLC methodologies can be thought of like a checklist of  the different stages that must be performed to develop and deliver  successful software applications. All SDLC methodologies share a common  ground of distinct phases that include planning, analysis, design,  building, testing, deploying, and maintenance. These SDLC phases provide  the outline of what a software application project entails.

In the following section, we are going to explore how software development lifecycles impact the software development process.

The Software Development Process

The  software development process, as with all great projects, starts with  an idea. It takes planning, preparation, and management of phases and  team members to reach a goal. SDLC is a mapped-out, regulated framework  that typically follows the following universal phases to deliver  high-quality software application.

SDLC phases

SDLC methodology

Formation phase

This  basic, initial phase is the inception of an idea for a solution that  improves an existing solution or develops an entirely new one. It helps  define the magnitude of the project to plan resources.

Requirement/Planning Phase

In  this phase, requirements are gathered to formulate a design plan for  the software application solution. This phase entails a thorough  analysis to assess user needs, feasibility, development, improvements,  and more. It is very important to include documentation to refine  requirements and keep a record of the solution’s development. This phase  involves the creation of a project charter which defines technical and  functional requirements.

Design Phase

This phase is  focused on the design aspect of the software application solution in  terms of the selected technical and functional requirements and the  results of the thorough analysis of the software’s viability.

Development Phase

This  phase is the “meat” of the software development process. In this phase,  software engineers are solely focused on building a prototype of the  solution to perform a code review and ultimately create the solution  itself. The team works on transforming software specifications into a  working and reliable solution.

Testing Phase

This crucial  phase tests the software to ensure that everything works as it intended.  In the testing phase, software engineers are able to detect defects,  bugs, and errors in the software solution and ultimately have a quality  product that meets business expectations. Quality Assurance (QA)  specialists perform a series of tests to evaluate the status of the  solution.

Release Phase

Once the software application is  fully developed and tested, it moves to the release phase. In this  phase, the software goes live and is released to the end user for actual  use of the product. In essence, the software is fully operational in a  live environment where end users utilize it.

Maintenance Phase

This  post-release phase is tasked with keeping the software completely  operational, updating it to meet quality standards, and enhancing it  throughout its life to ensure it continues to attract and retain users.

The  software development process sets the tone and defines a goal from  which developers kick-start a project. Ultimately, following a software  development process is intended to develop software faster and with a  few hiccups as possible.

Now that we’ve covered the universal SDLC  phases, let’s assess how important it is to follow software development  methodologies in an IT environment.

The importance of SDLC methodologies in an IT project

It  is rather unrealistic to think of a software development environment  where structure and defined processes aren’t needed. In an atmosphere  where there are so many variables, players and things that can go wrong,  it is imperative to have the help of guidelines and a “rulebook” you  can use as a standard to guide you through the process of delivering a  successful software application.

The importance of having and  following prescribed methodologies in software development lies in the  predictability of having a controlled environment for all development  efforts. Software Development cycles or methodologies, in essence, are a  series of stages or steps through which an organism, or in this case, a  software application, passes through in a series of recurrences to  reach the desired outcome. The lifecycle in software development follows  the life of a software application from its inception to its  maintenance, and developers need a level of control to ensure the  solution is consistent with the original requirements and the release of  the solution is properly managed.

Methodologies in software  development are repeatable processes that can be reused as many times as  necessary with a strong likelihood of delivering successful results if  applied correctly.

Working under SDLC methodologies provides the  opportunity to deploy solutions faster because it is a consistent,  repeatable and systematic approach. Additionally, it allows  organizations to respond better to market pressure and deliver  high-quality business applications due to its structure and systematic  nature which enables developers to work in a controlled environment.

Next,  we are going to cover some of the different software development  methodologies available to help users select the right fit for their  solution.

Selecting the right SDLC methodology for a project

In this section, we are going to cover some of the most prominent types of SDLC methodologies, which are:

Waterfall

Known as the traditional methodology, Waterfall is a sequential and linear flow for developing a software application.  The process is outlined by a series of finite stages, each of which must  be fully completed before moving on to the next one. The Waterfall  approach follows this order: requirements, design, execution, testing,  and release.

Advantages of Waterfall

It is structured and  easy to follow. The activities are well defined and it fosters careful  planning of the project. Additionally, it has specific deliverables at  each stage of the process.

Drawbacks of Waterfall

It is  unyielding and complex to go back to any stage after it is finished. It  has little flexibility to adjust to a changing scope. Additionally, it  is relatively more expensive than other methodologies and is more  time-consuming.

Prototyping

This methodology creates  prototypes of the software application to simulate the functioning  aspects of a desired, final product. Prototyping is mainly used to visualize components of the software solution and  match them with customer requirements. There are several variants of  prototyping but they are mainly categorized into throwaway and  evolutionary. Throwaway prototyping creates a model that will eventually  be discarded and evolutionary prototyping refers to a robust prototype  that will be constantly refined to reach its final version.

Advantages of Prototyping

A  functioning version of the software solution can help identify  potential risks and threats that can be dealt with in a timely manner,  reducing costs and time investment. Additionally, the user is involved  and can visualize a working version of the software.

Drawbacks of Prototyping

A  working prototype may cause confusion with the finished version of the  system. Oftentimes, developers end up wasting a significant amount of  time creating a prototype, and their time could have been t used in a  more valuable manner. Additionally, it can be costly to implement  functioning prototypes.

Spiral

The Spiral methodology can be thought of as a combination of the Waterfall  methodology and the prototyping methodology. It is typically the  methodology of choice for large and complex projects because it uses the  same stages as the Waterfall methodology but it separates them into  planning, risk assessment, and prototype building.

Advantages of Spiral

It  provides more realistic estimates in terms of workloads, budget, and  schedule as it discovers challenges and issues in its early stages. It  involves developers right from the get-go and manages both risks and the  system’s development in small phases of segments.

Drawbacks of Spiral

It  is a costly methodology that consumes a significant amount of time to  reach the desired solution. Additionally, it requires a team of  highly-skilled specialists who help evaluate risks and assumptions.

Agile

The iterative and incremental methodology known for excellence, Agile is a framework that evolves through collaboration between teams. It is a  dynamic and interactive methodology that works in sprints that have a  defined duration with lightweight deliverables that help reduce the time  in which software is released. It advocates for adaptive planning,  evolutionary development, early delivery, continuous improvement, and  rapid and flexible responsiveness to changes.

Advantages of Agile

High-quality  software,  which can then be further built upon with successive  iterations, is delivered in the least possible amount of time. It  includes a deep involvement from the client but it remains a very  flexible methodology as changes can be introduced at virtually any stage  of the project. Additionally, Agile fosters a high degree of  collaboration between cross-functional teams and all the involved  parties.

Drawbacks of Agile

It requires a team of  specialized developers who are solely focused on the project at hand and  have a specific set of skills. Agile can be challenging when scaling  projects and it also presents constant refactoring as changes are  frequent and even more so if the scope is not properly defined from the  early stages of the project.

Iterative and incremental

The iterative and incremental methodology is designed to overcome any fault or shortcoming of the  Waterfall methodology. The iterative and incremental methodology begins  with initial planning and ends with the deployment of the solution, with  cyclic interaction in between. In essence, it develops a software  application via iterative and repeated cycles that are performed  incrementally so developers can learn from the development of previous  portions of the software.

Advantages of iterative and incremental

It  delivers business value early in the development lifecycle and makes  better use of limited resources via incremental development. It is  flexible enough to adapt to changing requests between increments and is  more customer-focused than linear approaches.

Drawbacks of iterative and incremental

This  methodology requires heavy documentation efforts as it follows a  stringent set of processes. It requires a deep level of customer  involvement and can turn problematic when delimiting functions and  features.

V model

V model methodology  is considered an extension of the Waterfall methodology, but instead of  flowing down in a linear way, the steps are designed upward to form a V  shape. In this methodology, the relationships between each phase of the  development lifecycle are associated with a testing phase. The  horizontal and vertical axes display the time or project completeness  (left to right) and abstraction level (coarsest-grain abstraction).

Advantages of V model

It  is relatively easy to use and understand as it has specific  deliverables throughout each phase of the process. It carries out test  plans early on in the lifecycle which helps verify and validate the  product from the beginning.

Drawbacks of V model

It is  considered an inflexible model which makes it difficult to adjust the  project’s scope, which can ultimately turn expensive. There are no early  prototypes of the software and no clear path for issues discovered  during the testing phases.

This summary of some of the most  prominent SDLC methodologies paints an illustrative description of what  each solution entails and which one is best suited for specific project  needs and requirements, thus making it easier to select the right  methodology.

Next, we are going to talk about some of the most popular SDLC models.

These are some of the most popular SDLC models.

Continuous integration

With  Continuous Integration (CI), users can detect problems from the build  of a software application to its basic deployment. CI allows users to  detect and fix problems before they have the chance to cause significant  damage. In many environments, CI is considered a necessity for Agile  frameworks and to help meet business demands. In essence, with  Continuous Integration, all developer work copies are merged into shared  mainline multiple times a day to prevent integration problems.

Prototyping

In  this model, a prototype is built and developed to act, feel, and behave  like an early approximation of a final software solution. An ideal  prototype displays the expected functionality of a product under  development and is frequently used to demonstrate to customers who may  not have specific project requirements how the software can look and  function. Usually, a prototype is reworked and refined until it reaches  an acceptability stage from which a finalized solution can be developed.

Incremental development

The  incremental development model involves the design, implementation and  incremental testing of a software product until the product is finished.  The software product is not considered finished until it meets all of  the functional and technical requirements that were initially delimited.  It combines elements from the waterfall and prototyping methodologies.

Rapid application development (RAD)

It  is an adaptive approach that puts less emphasis on planning and more  emphasis on an adaptive process. Oftentimes, prototypes are used in RAD  to substitute design specifications. RAD is considered one of the most  popular SDLC models for software that is driven by user interface  requirements. From its origin, RAD was created as a response to the  plan-driven Waterfall methodology that designs and builds things almost  as structured as done with a building. RAD is all about fast prototyping  and iterative delivery that falls into the parental category of Agile.

These models help implement and take the most advantage of software development processes.

Conclusion

SDLC  methodologies are here to stay and evolve. These systematic solutions  to the challenge of developing software are a great starting point for  developers who embark upon the valuable task of creating a software  application solution.

Whether you are an advocate of a specific  methodology or solution, it is important to recognize the inherent value  and importance of selecting the right methodology for your software  project. We have an outstanding team of dedicated professionals who are skilled,  highly-specialized, and experts in helping design, build and deploy  software solutions that are successful for your needs.

For  more information, reach out to us and we’ll be happy to provide more  details and all the help you’ll need to reach your software development  goals.