1. ARCHITECTURAL MISMATCH Heather T. Kowalski September 5, 2000

2. Article Details “Architectural Mismatch: Why Reuse Is So Hard” By David Garlan, Robert Allen, & John Ockerbloom CMU Professor & Graduate Students IEEE Software, November 1995

3. Context ABLE Project –Architecture-Based Languages & Environments –To develop “foundations for an engineering discipline for software architecture” Aesop System –Tool designed to “experiment with architectural development environments”

4. Aesop Inputs of Style Description & Shared Infrastructure Aesop’s black box Manipulation Result: Custom Design Environment www.cs.cmu.edu/afs/cs/project/able/www/aesop/ aesop_home.html

5. Software Architecture Motivation –Depict a Complex System in Manageable Format –Identify & Exploit Recurring Elements

6. Software Architecture, con’t Research Areas –Architectural Description –Formal Underpinnings –Design Guidance –Domain Specific Architecture –Architecture in Context –Role of Tools & Environments

7. Harsh Realities Excessive Code Poor Performance Modify External Packages Need to Reinvent Existing Functions Unnecessarily Complicated Tools Error-Prone Construction

8. Conflicting Assumptions -- Taxonomy Nature of Components Nature of the Connectors Global Architectural Structure Construction Process

9. Nature of Components Infrastructure Control Model Data Model

10. Nature of Connectors Protocols –Event Broadcast –Request/Reply pair Data Model –C Constructs & Arrays –ASCII Strings

11. Global Architectural Structure Role of Tools –Independent Tools Concurrency = Conflict

12. Construction Process Existing Infrastructure Application Code Reuse/Integration Code Code Generated by other Packages

13. Future Design of Components Codify Notations, Mechanisms, and Tools Steps: –Explicitly Document Architectural Assumptions –Orthogonal Subcomponents –Sources of Design Guidance –Techniques for Bridging Mismatches