MBSE with CORE 100821

Bridging to and from Requirements: Use Case Diagrams

• Describe the functionality of a system from the user perspective • Elicit requirements from stakeholders

• Bridge to (elaborated by) system threads / behavior • Represent use cases, actors, and blocks • Complemented with

• Pre-conditions • Post-conditions • Primary flow • Exception flows

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Remember Our System Boundary

“Responsibility boundary” Externals systems are “actors” with which our system interacts Our system can be viewed from each actor to further the black box understanding of our system (elicitation of requirements) • Interfaces, flows, and dependencies • Externally observable functions (what the system does) • Performance and behavior as measurable at the boundary External systems and actors are represented as Components

Collectors

Customers

Geospatial Library

Customer Certification Authority

System Context

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MBSE with CORE