Reliability Support for the Model Driven Architecture Genana - PowerPoint PPT Presentation

Reliability Support for the Model Driven Architecture Genaína Rodrigues, Graham Roberts, Wolfgang Emmerich, James Skene {G.Rodrigues|G.Roberts|W.Emmerich|J.Skene}@cs.ucl.ac.uk Department of Computer Science University College London, UK WADS 2003

Motivation No standard approach for reliability in the architectural level. Extend MDA to provide reliability support Abstract away complexity of reliability support Achieve a platform-independent reliability model Integrate formal analysis and design of reliability in a unified semantic framework Genaína Rodrigues 2 WADS 2003

The Model Driven Architecture (MDA) What is MDA? Model, Abstraction and Refinement Profiles: The lightweight extension mechanism � Stereotypes � Tagged Values � OCL Genaína Rodrigues 3 WADS 2003

PIMs and PSMs Problem: Technical infrastructure changes independently of business rules, but these are strongly coupled in designs. Solution: Decouple them Platform Platform Specific Independent Model (PSM) Refinement Model (PIM) Genaína Rodrigues 4 WADS 2003

MDA Mapping PIM Metamodeling Language Analysis Results PSM PSM Source Code Genaína Rodrigues 5 WADS 2003

Our Approach Define a UML Profile for Reliability Implement the mapping from PIM to PSM for EJB Extend UML Profile for EJB Unified Framework Genaína Rodrigues 6 WADS 2003

Our Approach Real-Time UML Profile Specification Reliability Profile Mapping Profile Deployment Profile Genaína Rodrigues 7 WADS 2003

A Profile for Reliability A subset of UML meta-model: stereotypes, tagged values and OCL constraints Describe semantics of reliability mechanisms Reliability mechanisms � Clustering � Persistency � Message delivery assurance � Atomic Transaction Genaína Rodrigues 8 WADS 2003

A Scenario Reliability Assurance of the System: 1-(1-c) n > a c = reliability of each component a = required reliability of the system n = replicated components to assure a If c is 75%, a is 95% then n should be at least 3 Genaína Rodrigues 9 WADS 2003

A Scenario EJB Fail-Over Mechanism Entity Bean Replica 1 Container Entity Bean Client . Instance . . Container Entity Bean Replica n Container EJB Server Genaína Rodrigues 10 WADS 2003

Conclusion And Future Work Conclusion Highlighted the need to address reliability during design. Outlined an approach to integrating reliability specification into MDA Future Work Accomplishment of the Reliability Profile Map the J2EE reliability mechanisms in the UML/EJB profile (PSM) Automation for mappings Genaína Rodrigues 11 WADS 2003

Questions G.Rodrigues@cs.ucl.ac.uk http://www.cs.ucl.ac.uk/staff/g.nunesrodrigues Genaína Rodrigues 12 WADS 2003