What is SDLC? Phases of Software Development, Models, & Best Practices

Introduction:

The software development life cycle (SDLC) is a process used for structuring the development of any software system, from initiation through to implementation. An increase in demand for software to meet customer needs effectively but with less cost and faster delivery has put tremendous pressure on modern organizations. To stay competitive, companies must build their software correctly and transform their businesses by following efficient software engineering methodologies, practices, and concepts. Without meeting these changes, there can be a drop in productivity, leading ultimately to business failure. Customer interaction at all levels with the right methodology for implementing the software is crucial to any organization’s success.

What is the first step in the Software Development Life Cycle?

The first step in the software development life cycle (SDLC) is requirement analysis. The first phase includes a collection of all the data from the customer. This includes the expectations of the customer. An understanding of what the product is, who the target audience is, why the product is being built is considered. Once the requirements are gathered, they are analyzed. An analysis of how feasible the creation will be is made. Any further ambiguity is discussed. Once the requirement is understood clearly and the analysis made, the SRS (Software Requirement Specification), is created. This document is for the benefit of both the software developers and the customer. It can be referred to by both parties for convenience.

Five different SDLC stages are:-

1. Planning and analysis
2. Designing the product architecture
3. Developing and coding
4. Testing
5. Maintenance

1. Planning and analysis

This phase is the most fundamental in the SDLC process. Business requirements are compiled and analyzed by a business analyst, domain expert, and project manager. The business analyst interacts with stakeholders to develop the business requirements document. They also write use cases and share this information with the project team. The aim of the requirements analysis is for quality assurance, technical feasibility, and to identify potential risks to address in order for the software to succeed.

2. Designing the product architecture

During the design phase, lead developers and technical architects create the initial high-level design plan for the software and system. This includes the delivery of requirements used to create the Design Document Specification (DDS). This document details database tables to be added, new transactions to be defined, security processes, as well as hardware and system requirements.

3. Developing and coding

 In this phase, the database admin creates and imports the necessary data into the database. Programming languages are defined by requirements. Developers create the interface as per the coding guidelines and conduct unit testing. This is an important phase for developers. They need to be open-minded and flexible if any changes are introduced by the business analyst.

4. Testing

Testers test the software against the requirements to make sure that the software is solving the needs addressed and outlined during the planning phase. All tests are conducted as functional testing, including unit testing, integration testing, system testing, acceptance testing, and non-functional testing.

5. Maintenance

In a post-production, live software environment, the system is in maintenance mode. No matter the number of users, the sophistication of the software, and rigorous QA testing, issues will occur. That’s the nature of software with managing data, integration, and security, and real-world usage. Access to knowledgeable, reliable support resources is essential, as is routine maintenance and staying up to date on upgrades.

Read More: https://www.charterglobal.com/enterprise-solutions/

SDLC Models & Methodologies Explained

1. Waterfall

The Waterfall SDLC model is the classic method of development. As each phase completes, the project spills over into the next step. This is a tried-and-tested model, and it works. One advantage of the Waterfall model is each phase can be evaluated for continuity and feasibility before moving on. It’s limited in speed, however, since one phase must finish before another can begin.

2. Agile

The AGILE model was designed by developers to put customer needs first. This method focuses strongly on user experience and input. This solves much of the problems of older applications that were arcane and cumbersome to use. Plus, it makes the software highly responsive to customer feedback. Agile seeks to release software cycles quickly, to respond to a changing market. This requires a strong team with excellent communication. It can also lead to a project going off-track by relying too heavily on customer feedback.

3. Iterative

In the Iterative development model, developers create an initial basic version of the software quickly. Then they review and improve on the application in small steps (or iterations). This approach is most often used in very large applications. It can get an application up and functional quickly to meet a business need. However, this process can exceed its scope quickly and risks using unplanned resources.

4. DevOps

The DevOps security model incorporates operations – the people who use the software – into the development cycle. Like Agile, this seeks to improve the usability and relevance of applications. One significant advantage of this model is the feedback from actual software users on the design and implementation steps. One drawback is that it requires active collaboration and communication. Those additional costs can be offset by automating parts of the development process. Read our detailed comparison of DevOps vs. agile.

Best Practices in Software Development

1. Develop Iteratively

• Critical risks are resolved before making large investments
• Initial iterations enable early user feedback
• Testing and integration are continuous
• Objective milestones provide short term focus

2. Manage Requirements

• Requirements are dynamic - expect them to change during software development
• Users own understanding of the requirements evolves over time
• Gain agreement with the user on what the system should do and not how
• Maintain forward and backward traceability of requirements

3. Use Component-Based Architecture

• Using components permits reuse
• Choice of thousands of commercially available components
• Improved maintainability and extensibility
• Promotes clean division of work among teams of developers

4. Visually Model Software

• Visual modeling improves our ability to manage software complexity
• Capture the structure and behavior of components
• Hide or expose details as appropriate for the task
• Promote unambiguous communication

5. Verify Software Quality

• What is quality? - The characteristic of producing a product that meets or exceeds agreed upon requirements by some agreed-upon objective measures.
• Software problems are 100 to 1000 times more costly to find and repair after deployment
• Develop test suites for each iteration and test for – Functionality, Reliability and Performance

6. Control Changes to Software

• Without explicit control parallel development degrades to chaos
• Decompose the architecture into subsystems and assign the responsibility of each subsystem to a team. Establish secure workspaces for each team i.e. each team is isolated from changes made in other workspaces.

Conclusion: The Process for Software Development

SDLC shows you what’s happening, and exactly where your development process can improve.

Like many business processes, SDLC aims to analyze and improve the process of creating software. It creates a scalable view of the project, from day-to-day coding to managing production dates.

Reference Link:

https://www.charterglobal.com/best-practices-for-requirements-analysis-gathering/

https://www.charterglobal.com/accelerating-software-development/

https://www.charterglobal.com/what-are-the-5-phases-in-the-software-development-life-cycle-sdlc/