Functional/Non-functional Requirements Flashcards
What are function requirements?
This describes functionality or system requirements. How the system should react to particular inputs and how the system should behave in certain situations.
Difference between functional user requirements and functional system requirements
Functional user requirements may be high-level statements of what the system should do but functional system requirements should describe the system services in detail
Examples of functional requirements
User id and password for user access. Document formats. Password recovery.
Problems with Requirements
Requirements can be ambiguous.
what two things should requirements be?
Complete - include descriptions of all facilities require. Consistent - should be no conflicts or contradictions in the descriptions of the system facilities.
What are non-functional Requirements?
Define system properties and constraints. (ex storage requirements etc). Process requirements(programming language etc).
What are some classifications of non-functional requirements?
Product requirements- behaviour of product in a specific way.
Organisational requirements - consequence of organisational policies and procedures (standards).
External requirements - factors which are external to the system and its development process. (legislative)
Performance
Since non functional requriements may be hard to state precisely what is a verificable non-functional requirement?
A statement using some measure that can be objectively measured.
What is a goal?
A general intention of the user such as ease of use.
What is common between DIFFERENT non-functional reqirements?
conflicts
Describe two problems with domain requirements
Understandibility and Implicitness (stating exactly what you want).
What are some problems with natural language?
Lack of clarity, requirements confusion, requirements amalgamation (several different requirements may be expressed together).
What are some guidelines to writing requirements?
Invent a standard format. Use language in a consistent way. Use text highlighting. Make documents self contained (include examples and glossaries).
