SOFTWARE DEVELOPMENT LIFE CYCLE

Software Development Life Cycle (SDLC)

• a process used by software industry to design, develop and test high quality software

• Aims to produce high quality software that meets/exceeds customer expectations, reaches completion within time and cost estimates

• Consists of a detailed plan describing how to develop, maintain, replace, alter, or enhance specific software

1. Planning

2. Defining

3. Designing

4. Building

5. Testing

6. Deployment

7. Maintaining

Stages of the SDLC

Planning

• Most crucial step in creating a successful system

• During this phase you decide exactly what you want to do and the problems you’re trying to solve, by:

1. Defining the problems, the objectives and the resources such as personnel and costs.

2. Studying the ability of proposing alternative solutions after meeting with clients, suppliers, consultants and employees.

3. Studying how to make your product better than your competitors’.

• After analyzing this data you will have three choices:

1. develop a new system

2. improve the current system or

3. leave the system as it is

Defining

• Determine and document the end-user's requirements and expectations for system performance.

• Conduct a feasibility study to assess if the project is organizationally, economically, socially, and technologically viable.

• Maintain strong communication with clients to ensure a clear vision of the finished product and its function.

Designing

• Follows a complete understanding of customer requirements.

• Defines the system's elements, including components, security level, modules, architecture, interfaces, and data types.

• Involves creating a general system design (concept/sketch) followed by a detailed and expanded system design that meets all functional and technical requirements (logically and physically).

Building

• Follows a complete understanding of system requirements and specifications.

• This is the actual construction process based on the complete design.

• The actual code is written.

• If the system includes hardware, this phase involves configuration and fine-tuning of the hardware.

Testing

• Aims to ensure customer satisfaction; no knowledge of coding, hardware, or design is required.

• Can be performed by real users or a specialized team.

• can be systematic and automated to ensure actual outcomes match predicted and desired outcomes.

Deployment

• The system is installed at the customer's premises, ready to become live and productive.

• Training may be required for end-users to ensure they know how to use the system and become familiar with it.

Maintaining

• An ongoing process after deployment to keep the software functional and relevant.

• Involves addressing bugs, improving performance, adding new features, and adapting to changing user needs.

Business Rules

• A statement that defines or contains some aspect of the business

• A brief, precise, and unambiguos description of a policy, procedure, or principle within a specific organization

• Ex. A student may register for a section of a course only if he or she has successfully completed the prerequisites for that course.

• Ex. A preferred customer qualifies for a 10 percent discount, unless he has an overdue account balance.

Describes what a process validates

What does a business rule describe?