Reference: ITIL v3: Service Design, chapter 5
Requirements are defined together with the business. Business comes up with an idea. Initial estimates should be done and then the initiative is either approved or not. Once approved, it comes to IT for analysis & design. BAs and designers should perform these activities.
Functional requirements
Functional requirements are expressed in the form of User Stories. These are scenarios that are easily translated into test cases.
This identifies processes, artifacts, roles, the domain model, state charts, flowcharts, interaction diagrams.
Functional requirements can be expressed as User Stories.
Management and operational requirements
Non-functional requirements. Categories:
Usability requirements
Represents ease of use.
Documenting requirements is best done in two distinct phases - building the requirements list and developing an organized requirements catalogue.
Each requirement in the list is checked to see whether it is well formed and SMART (Specific, Measurable, Achievable, Realistic, and Timely).
Checklist for assessing the individual and totality of requirements:
Potential outcomes from the exercise:
Flow:
Idea, Initial estimation & approval -> Analysis & Design -> Implementation -> Transition
Related topics: Cross-Cutting Concerns.