The SDLC dictates the process to be followed to develop a high quality software product and maintain it. The SDLC has an inherent feedback mechanism that allows the development team to fine tune the software product to meet the client requirements perfectly. It is critical for businesses and entrepreneurs, who are new to the field of software development, to understand the SDLC in its entirety, so that they are able to deliver better customer satisfaction and set their organization stays on a high growth path. So, let’s understand SDLC in greater detail.
What is Software Development Lifecycle?
Software Development Lifecycle is a systemic, step-by-step procedure for developing the highest quality software product, at the lowest cost, in the lowest possible time. The SDLC is a 7-step procedure which dictates how a software product should be designed, developed, maintained, and improved over time. The different phases of SDLC are sequential in nature and it is crucial to follow them according to the predefined sequence in order to obtain maximum benefit from them.
Why is Software Development Lifecycle important?
The SDLC accomplishes 3 seemingly disparate and often diverging objectives involved in the development of a software – improving quality, reducing the production cost, and shortening the production time.
The SDLC achieves these objectives by anticipating and eliminating the common and costly pitfalls that are encountered by the software developers. The entire process is streamlined to guide the developers through the path to successful development of a high quality, working, and intelligently designed software product that is designed from the ground up to meet the client requirements.
Different Phases of a Software Development Lifecycle
The following are the 7 distinct phases in every software development lifecycle.
1. Requirement Gathering and Analysis
This is a critical phase in every SDLC. Getting it right is extremely vital for the success of the project.
The primary focus of this phase is to obtain the business requirements for the software product. There is a great deal of brainstorming and communication between project managers, clients, and software developers to understand the client’s expectations from the software to be developed. Then, a BRS (Business Requirement Specification) is created, which records the client requirements in a painstakingly detailed manner.
If the software to be developed is a consumer-facing product, then extensive surveys, focus groups, and other primary research methods can also be conducted to obtain highly specific data and deep insights into the end consumers’ usage behaviors and expectations. If required, use cases can be created to get a better understanding of how the consumer will use the product.
The outcome of this phase is a near exhaustive set of information about the product’s expected capabilities. Such information is obtained by asking the stakeholders – be it clients, their employees, or their customers – highly relevant questions such as who will be using the product? What should be the inputs and outputs of the product? What hardware should the product be compatible with? Questions like these help the project managers get a better understanding of their client’s vision for the product.
In some cases, it might be necessary for the development team to develop a prototype, just to show the client what the end product looks like, so that there are no disappointments or confusion at a later point.
2. Feasibility Study
This phase is also known as the Planning phase. In this phase, various departments, including the core development team, human resource, finance department, business analysts, and project managers sit together and plan the execution of the project based on the BRS (Business Requirement Specification) created during the previous phase. They allocate the resources, estimate the costs involved, discuss the various risks associated with the project, and take into consideration other factors that affect the success of the project. For every major plan, secondary plans are created, then tertiary plans, and so on. This way, a clear picture emerges with regards to the execution of the project.
Now, it is decided whether the project is feasible based on the costs, time, resources, and other relevant factors.
It is during this phase that the BRS is translated into a technical design requirement document for the coding team. The lead developers and/or architects take the business requirements from BRS and create extensive technical requirements out of them. This design works like a blueprint for the coders to refer to when creating the software. It will have detailed technical specifications like hardware and system requirements, functionalities to be provided, database tables to be added, security measures to be incorporated, and so on.
When sensitive personal data is being collected from the users of the product, the legal department may also be consulted for its expertise.
This phase is where the magic happens.
In most projects, the coding phase is the longest phase of the SDLC. It begins when the developers have the design document ready for them from the previous phase. They start coding and developing the software product in the programming language as specified by the design document.
To ensure greater success of the project, it is a good practice for the coding team to demonstrate the completed work to the marketing team or the business development team after every milestone to get their input. As these departments are usually the closest to the clients and end users, and have a better understanding of what they need. Therefore, the coders need to be open-minded and flexible to the changes and improvements that they are suggested during this phase.
Once the software product is developed, it is sent for testing.
The testing engineers receive the full-fledged software product in the testing environment, where they subject it to rigorous testing. The objective of this phase is to check whether all the functionalities and features of the applications are working exactly as per the requirement of the client. The testing phase also covers hardware integration test and system testing.
It is common to find a number of bugs and defects in an application in the testing phase. When that happens, the testing engineers promptly send the test results to the developers, who fix the bug and send the application to the testing again. This circular process continues until the application becomes stable, works at a satisfactory level or is completely free of bugs, depending on the time criticality of the project.
Once the technical testing is complete, the product is sent to the end users for user testing. If the product is deemed to meet the user’s expectations, then the implementation and deployment begins.
6. Implementation or Deployment
This is the phase which marks the actual roll out of the software product to the end users. The early users are provided beta access to the application. If they notice any bugs, they report them to the development team, who fix them in the final official release of the product.
Continuous improvement is an essential step in every software development lifecycle. As more and more users start using a software product, they begin to encounter new bugs in the system, which need to be fixed on an urgent basis. In addition, the real world conditions keep changing and the software should be modified to adapt to those changes. Hence, regular updates and software patches become essential.
There are seven different SDLC models for developing a software product. These include Waterfall Model, Spiral Model, Prototype Model, V-Model, Iterative model, and Agile Model. Each model comes with its own set of benefits. The type of model to be chosen for developing a particular software is based on the project’s objectives, organization size, customers, time, and other factors.