Identifying design requirements
The design requirements specify the functions that the design must perform and the objectives that the design must meet.
There are two types of requirements: functional requirements and nonfunctional requirements. Functional requirements specify the objectives or functions that a design must meet. Nonfunctional requirements define how the design accomplishes the functional requirements.
Typical functional requirements include the following:
- Business goals
- Business rules
- Legal, regulatory, and compliance requirements
- Application system requirements
- Technical requirements
- Administrative functions
Typical nonfunctional requirements include the following:
- Performance
- Security
- Capacity
- Availability
- Manageability
- Recoverability
When identifying and defining the requirements, separate the functional requirements from the nonfunctional requirements. Nonfunctional requirements are design constraints and will be documented separately.
Since functional requirements define what the design...