1. Architecture Analysis and Design Language: An Overview Drew Gardner

2. Background Communication and agreement needed 2002 study: $59.5 billion annual to fix errors UML AADL

3. Origins Originally Avionics Architecture Description Language Based on similar language MetaH

4. Purpose Model real time embedded systems Not diagrammatic like UML Written like programming language Unambiguous

5. Usage Avionics Aerospace Automobiles Any constrained environment

6. Design Programming language Compilable 3 abstraction categories: software, hardware, composite

7. Components Software  Thread  Thread group  Process  Subprogram  Data Hardware  Device  Memory  Bus  Processor Composite  System  Package

8. Components (cont)

9. Type Declarations Extends: Inheritance Features: Interacting components Flows: Logic and control flows Properties: Attributes

10. Implementation Declarations Refines: Override properties Subcomponents: Internal implementations Calls: Call subprograms Connections: Interactions involving ports and data

11. Summary Rough rule: type = class, implementation = object Detailed description of software and hardware interactions

12. Example 1 Process control mechanism Simple; incomplete

13. Example 1 Diagram

14. Example 2 End to end flow Flow wholly contained within component Brake pedal causes cruise control to change throttle

15. Conclusions AADL is effective analysis and design tool Wide array of capabilities, can also be extended Does not compete with UML; complements