Requirements Development An Introduction to the Process and Artifacts November 20, 2001 SIS Analysis Model System Analysis Model SIS Use Case Model System Use Case Model

SIS Analysis Model System Analysis Model SIS Use Case Model System Use Case Model 2 Objectives Complete, consistent, accurate requirements. Faster and higher quality impact analysis. Foundation to begin design Faster and more systematic testing. Decrease new team member’s learning curve. Single source of a system’s requirements.

Requirements Development Process Use Case Models Class Diagrams Use Case Scenarios Sequence Diagrams Story Boards Software Reqmts Spec Identify Use Cases Model Problem Realize Use Case Scenarios Specify Requirements Specify Use Case Scenarios Storyboard Use Case Scenarios

SIS Analysis Model System Analysis Model SIS Use Case Model System Use Case Model 4 Use Case Model

SIS Analysis Model System Analysis Model SIS Use Case Model System Use Case Model 5 Use Case Scenario

SIS Analysis Model System Analysis Model SIS Use Case Model System Use Case Model 6 Analysis in Brief Use Cases are used to gather requirements, they are: 1. Kept as independent of each other as possible Issue: Interference, concurrency, and conflicts among use cases may thus be unresolved 2. Described using the language of the customer Issue: Precision and details may be unresolved 3. Structured to form a complete and intuitive specification of functionality Issue: Redundancies among described requirements may be unresolved The primary purpose of analysis is to resolve these issues

SIS Analysis Model System Analysis Model SIS Use Case Model System Use Case Model 7 Analysis Model

SIS Analysis Model System Analysis Model SIS Use Case Model System Use Case Model 8 Receive Order Sequence Diagram

Direct+ Sequence Diagram

SIS Analysis Model System Analysis Model SIS Use Case Model System Use Case Model 10 Software Requirements Specification

Test Case Use Case Driven SRS Centric Use Case Driven SRS Centric

SIS Analysis Model System Analysis Model SIS Use Case Model System Use Case Model 12 Impact Analysis Analyze User Requirements Specify New Use Case Change Use Case Modify Existing Requirement Modify Class Diagram Realize Use Case Use Case Models Class Diagrams Use Case Scenarios Sequence Diagrams Story Boards Software Reqmts Spec

OK Fail Class/Code Desired End State SIS Requirements System Requirements Design Test Implemen-tation Class/Code OK Fail SIS Analysis ModelSystem Analysis Model System Requirements Design ModelImplementation Model Test Model SIS Use Case ModelSystem Use Case Model Design Implemen-tation Test

SIS Use Cases vs System Use Cases A C B Actor 1Actor 2 System of Interconnected Systems (SIS) Actor 2 A1 B1 A2 B2 C2 A3 C3 Actor 2System X A2 B2 C2 System Z System XSystem YSystem Z System Y