Explanation:
This type of question are asked to create confusion.
Following are the five phases of SDLC:
1. Planning and requirements analysis: Business and security requirements and standards are being determined. This phase is the main focus of the project managers and stakeholders. Meetings with managers, stakeholders, and users are held to determine requirements. The software development lifecycle calls for all business requirements(functional and nonfunctional)to be defined even before initial design begins. Planning for the quality-assurance requirements and identification of the risks associated with the project are also conducted in the planning stage. The requirements are then analyzed for their validity and the possibility of incorporating them into the system to be developed.
2. Defining: The defining phase is meant to clearly define and document the product requirements to place them in front of the customers and get them approved. This is done through a requirement specification document, which consists of all the product requirements to be designed and developed during the project lifecycle.
3. Designing: System design helps in specifying hardware and system requirements and helps in defining overall system architecture. The system design specifications serve as input for the next phase of the model. Threat modeling and secure design elements should be undertaken and discussed here.
4. Developing: Upon receiving the system design documents, work is divided into modules or units and actual coding starts. This is typically the longest phase of the software development lifecycle. Activities include code review, unit testing, and static analysis.
5. Testing: After the code is developed, it is tested against the requirements to make sure that the product is actually solving the needs gathered during the requirements phase. During this phase, unit testing, integration testing, system testing, and acceptance testing are conducted.