How a system operates, how it performs, what it’s appearance should be, is often described in non-functional requirements. Within this group we find coverage types like operational and load profiles, and presentation.
Coverage types in this group are:

  • Information security-based
    ◦ Authorisation
    ◦ Authentication
    ◦ Communication security
    ◦ Data confidentiality
    ◦ Data integrity
    ◦ Non-repudiation
    ◦ Privacy
  • Performance-based
    Load profiles
    Operational profiles
  • Presentation
  • Usability-based
    ◦ Alpha-testing
    ◦ Beta-testing
    ◦ Usability lab