Software Development Life Cycle or SDLC is the process of developing a software from initial state to production state and beyond.
SDLC explains step by step practices from designing a software to developing and providing to customer. Over the years this process has been improved and it allows the team assign the tasks to team members, measure them and complete them.
The goal of SDLC is to minimize the software development risk through forward planning so the produced software satisfy customer needs and requests.
Usually SDLC contains following phases of development:
- Requirement analysis
- Planning
- Software Design
- Software Development
- Testing
- Deployment
In this article we will check out together how Software Development Life Cycle (SDLC) works including:
- What is SDLC?
- Is SDLC important?
- How SDLC works and helps in systematic development?
- Different SDLC Models
- SDLC phases and best practices to do
What is SDLC?
As explained in the intro, SDLC is a methodology for developing software. SDLC aims to present highest quality software with lowest cost in minimum possible time.
There are different phases in SDLC along with different models. As the phases introduced above, some of the models are Agile Model, Waterall Model and Spiral Model.
Is SDLC important?
SDLC or Software Development Life Cycle is important as it provides a way to manage the developing software. Problems that can occur during software development are cross functional collaboration, requirement changes, technology upgrades and etc. These and other possible problems getting cover within a comprehensive system called SDLC.
By dividing the development efforts to different phases, it categorizes problems and helps in managing them more efficiently. Before each project starts, all the stakeholders and team managers agree on deliverables and specifications in each phase.
In summary SDLC provide these benefits:
- SDLC improves visibility between all the project members
- Estimation, planning and scheduling are more reliable
- Risk and cost are more manageable
- better client satisfaction as a result of systematic development
How SDLC works and helps in systematic development?
SDLC lowers the cost of development while improving the quality of the product at the same time. It follows a plan that removes the unnecessary software development pitfalls and common problems.
It starts by evaluating existing systems for deficiencies. Next software requirement and specifications are defined. Then based on tehse analysis different stages are planned. These stages include:
- Analysis
- Planning
- Design
- development
- Testing
- Deployment
By anticipating costly mistakes, SDLC removes redundant rework and prevents unnecessary fixes in early stages.
It’s important to mention SDLC has a focus on testing. As SDLC is a repetitive process, in each phase it relevant test types should be applied to ensure removal of maximum bugs in that phase.
Many organizations and companies tend to dismiss testing efforts but testing usually mean less cost in long run as it saves lots of rework time and money.
It is highly recommended to perform suitable type of tests in each phase.
Here’s different phases of Software Development Life Cycle visually
Different SDLC Models
As every project and every team is not the same, SDLC provides different models suitable for different situations. Each model presents SDLC in an organized fashion tha can be implemented by the teams. Let’s dive deeper and check out these models together.
Waterfall Model
The waterfall model behaves each phase sequentially. So the next phase is dependent on the result of previous phase and that’s why it is called waterfall model. Conceptually waterfall model design is one phase flow down to the next phase
Pros and Cons Waterfall model
Waterfall model is more useful in smaller projects where the requirements has been defined accurately and less probable for change.
This model works in a way after each phase done, team won’t get back to the completed phases and as a result changes are more costly in waterfall model. However it is suitable for measuring the progress and quality of the app there is little room for new changes which sometimes even in small projects is unpreventable.
Spiral Model
Spiral model is the most flexible model in SDLC. This model emphasizes on repetition. The spiral model go through the planning, design, build and test phases over and over again, with gradual improvement.
Spiral model is more suitable for larger project and it will be costly to use it for smaller projects.
Agile Model
In Agile model SDLC phases go into several development cycles. Development team iterates through the phases rapidly developing, delivering and providing changes only in small parts.
Agile model is suitable for quickly reacting to changes as the team evaluates requirements, plans and results frequently. It is believed Agile model is more efficient in comparison with other models due to its iterative and incremental nature.
Pros and Cons of Agile Model
Rapid development cycles the project prevent from major bugs as rapidly problems getting identified and fixed usually in early stages. Also it makes it possible to have feedback from stakeholders and client during the development.
However it’s a common problem in agile which over reliance on client feedback cost a lot and sometimes lead to termination of the project midway.
Iterative Model
Iterative model focuses on iteration. One low cost and initial version is getting developed and team iterate over it again and again making improvements. If it’s not monitored correctly it can eat up resources very fast.
SDLC phases and best practices to do
Following the best practices in each phase of SDLC ensures a high quality product and happy client. Let’s explore how we can improve our efforts in each of these phases
Detecting current problems
“What is the current problem?” This is the main and one of the most important questions managers, stakeholders, sales people, industry leaders and everyone else ask and discuss to find out what’s the current problem and what should be implemented and improves.
This question will make it clear how the software will fill the gap and fulfill a need. It’s the aim of the developing software.
Planning
In this stage, team plans the project based on requirements and resources. Risks also getting evaluated and sub plans getting created for more smooth development.
Team discuss together the feasibility of the project how it can be developed more efficiently.
Design
“How will we get what we want?” In this phase the team finds out the structure of the software and based on it visual design get done. All stakeholders provide feedback in this phase and it’s crucial to gather the provided info in this phase.
failure in phase can be really costly as it can terminate the project and good scenario, failure can make costly changes in the future.
So it’s very important to pay more attention on the infrastructure of the software in this phase.
Build
Coding get started in this phase. All the preparations and designs are getting converted to code. Different coding teams as Back end and Front end, coding on their parts based on their plans.
It is important to code based on same guidelines within the team, so changing or returning to the code will be much more efficient.
Testing
As the vital part of the SDLC, testing getting done in this phase. Testing team will verify the code and software to check if the developed software satisfy the requirements and if the quality of the application is acceptable.
This phase getting repeated until the software is in acceptable quality and can be provided to the client for initial feedback.
Deployment
In this phase the developed software getting deployed to the production server.
Sometimes teams, use another server called stage server to showcase the project to client as a final stage for moving the software to the market.
So depending on the company policies there can be multiple server as developing server, testing, stage and production.