Using the Vanderbilt Generic Modeling Environment (GME) to Address SOA QoS Sumant Tambe Graduate Intern, Applied Research, Telcordia Technologies Inc. June 17, 2009

2 / 13 Outline  Introduction to Model Integrated Computing (MIC) – 4 layer meta-level architecture  Overview of GME – Background, architecture, metamodeling, and tooling  Examples of Domain-Specific Modeling Languages (DSMLs) – Component QoS Modeling Language (CQML)  Tutorial for creating a simple structural SOA modeling language using GME

3 / 13 Model Integrated Computing (MIC)  Motivation – Design documents are not just documentation, they are part of the system.  Capture specification in the form of domain models – Ideally, correct-by-construction – Higher level and highly intuitive – Speak the language of the domain  Automate system development process – Formal analysis, simulation, platform-specific code/configuration generation, deployment meta-data, etc.

4 / 13 Defining domain models (Metamodeling) switch (state) { case ‘A’: /*... */ case ‘B’: /*... */ M3 M2 M1 M0

5 / 13 Generic Modeling Environment (GME) – A mature metamodeling tool  Developed at Institute for Software Integrated Systems (ISIS), Vanderbilt University  Under development since 1995  Supports 4-layer metamodeling architecture  API support in C++, Java, Python  Different model storage formats: database, binary, XML  Classic paper: Composing Domain-Specific Design Environments, Akos Ledeczi et al., IEEE Computer, Nov 2001

6 / 13 GME Editor (M1) snapshot Parts browser with custom icons A graphical domain model of signal flow graphs Tree view

7 / 13 Architecture of GME Event-driven Drag and drop Expand/Collapse Multi-view Object Constraint Language (OCL) API for model manipulation (R/W) (C++, Java, Python)

8 / 13 Metamodeling Using GME  MetaGME: GME’s metamodeling language (M3)  MetaGME is meta-circular (can describe itself)  Very similar to UML class diagrams  Supports general modeling concepts such as – First class domain concepts (classes) – Textual, numerical, and enumerated attributes – Hierarchy (UML composition) – Connection (UML association) – Inheritance (interface/implementation inheritance) – Reference – Multi-aspect modeling (view-per-concern)

9 / 13 Defining Domain Specific Modeling Languages (DSMLs) Using GME  DSMLs capture the domain formally – E.g., State machines, Component-based systems, Web page navigation modeling language  Only allows ”valid” sentences in the domain – Correct-by-construction  Every DSML has 3 parts – Abstract syntax (relationship of the domain concepts) – Concrete syntax (textual, graphical, tabular) – Semantics  Static semantics specified using metamodel cardinalities & OCL  Dynamic semantics implemented using translators

10 / 13 A DSML Example: Component QoS Modeling Language (CQML)  Hierarchical structuring of component-based systems

11 / 13 CQML QoS Modeling(2/2)  FailOverUnit – Annotate protected components and assemblies – Specify # of replicas  Network-level QoS – Annotate component connections – Specify priority of communication traffic – QoS provisioning using differentiated services – Work done with Telcordia in 2006!  Security QoS – Annotate component ports or connections – Controls role-based access control (RBAC) Policies

12 / 13 A Prototype Structural SOA Modeling Language Using GME Metamodel

13 / 13 Thank you!