Functional and Non-functional requirements
I. Types of Requirements :
A. What is functional requirements ?
A functional requirement defines a function of a system or its component. A function is described as a set of inputs, the behavior, and outputs . Functional requirements may be calculations, technical details, data manipulation and processing and other specific functionality that define what a system is supposed to accomplish.
B. What is Non-functional requirements ?
A non-functional requirement is a requirement that specifies criteria that can be used to judge the operation of a system, rather than specific behaviors. This should be contrasted with functional requirements that define specific behavior or functions. The plan for implementing functional requirements is detailed in the system design. The plan for implementing non-functional requirements is detailed in the system architecture.
II. Requirements Elicitation :
A. What is the needs, goals and requirements for Elicitation ?
Goals :
1. Identify the real problem, opportunity or challenge
2. Identify the current measure(s) which show that the problem is real
3. Identify the goal measure(s) to show the problem has been addressed and the value of meeting it
4. Identify the "as-is" cause(s) of the problem, as it is the causes that must be solved, not the problem directly
5. Define the business "whats" that must be delivered to meet the goal measure(s)
6. Specify a product design how to satisfy the real business requirements
Needs :
1. 'Problems of scope'. The boundary of the system is ill-defined or the customers/users specify unnecessary technical detail that may confuse, rather than clarify, overall system objectives.
2. Problems of understanding. The customers/users are not completely sure of what is needed, have a poor understanding of the capabilities and limitations of their computing environment, don’t have a full understanding of the problem domain, have trouble communicating needs to the system engineer,
A. What is functional requirements ?
A functional requirement defines a function of a system or its component. A function is described as a set of inputs, the behavior, and outputs . Functional requirements may be calculations, technical details, data manipulation and processing and other specific functionality that define what a system is supposed to accomplish.
B. What is Non-functional requirements ?
A non-functional requirement is a requirement that specifies criteria that can be used to judge the operation of a system, rather than specific behaviors. This should be contrasted with functional requirements that define specific behavior or functions. The plan for implementing functional requirements is detailed in the system design. The plan for implementing non-functional requirements is detailed in the system architecture.
II. Requirements Elicitation :
A. What is the needs, goals and requirements for Elicitation ?
Goals :
1. Identify the real problem, opportunity or challenge
2. Identify the current measure(s) which show that the problem is real
3. Identify the goal measure(s) to show the problem has been addressed and the value of meeting it
4. Identify the "as-is" cause(s) of the problem, as it is the causes that must be solved, not the problem directly
5. Define the business "whats" that must be delivered to meet the goal measure(s)
6. Specify a product design how to satisfy the real business requirements
Needs :
1. 'Problems of scope'. The boundary of the system is ill-defined or the customers/users specify unnecessary technical detail that may confuse, rather than clarify, overall system objectives.
2. Problems of understanding. The customers/users are not completely sure of what is needed, have a poor understanding of the capabilities and limitations of their computing environment, don’t have a full understanding of the problem domain, have trouble communicating needs to the system engineer,