Grid-based interoperability of workflow systems Moustafa Ghanem, InforSense Ltd Nabeel Azam Mike Boniface InforSense Ltd IT Innovation

Background: SIMDAT Developing and applying Grid technology to support Distributed, Cross-organizational, product and process development Four sectors of international economic importance: Automotive Pharmaceutical Aerospace Meteorology Seven Grid-technology development areas: Grid infrastructure Distributed Data Access VO Administration Workflows Ontologies Analysis Services Knowledge Services

Example Auto design workflows

Example Aero design workflows Aerodynamics (BAE) Design (UoS) Compute (UoS)

S7 S8S9 S4S5S6 S1S2S3 SOA and Workflows: A programmer’s view ToolsData Services Service Provider IService Provider IIService Provider III ToolsData ToolsData Organization IOrganization IIOrganization III

Key challenge for workflow in SIMDAT There are 26 partners in SIMDAT At least 3 workflow systems in use –InforSense KDE –Taverna/Freefluo –LMS Optimus –Other approaches include Various hard-coded wf applications BPEL Agreeing/Using a common workflow system (or language) is difficult –Migration may require huge re-investments –Continued debate on open source vs. proprietary In general, virtual organizations are dynamic –What happens when we add new partners? Capability Providers Grid Technologists End Users SIMDAT partners

Workflow Systems: Are they really similar?

Workflow systems quick comparison Similarities –All have drag-drop GUIs –All use XML-based languages –Similar conceptual model Differences –Different language paradigms/semantics Pure Data Flow vs. Control Flow –Iterations (not available, implicit, explicit ?) Data types and operators supported –Varying degrees of abstraction Node granularity Service call vs. abstract task –Different systems specialized to particular applications Specialized viewers Specialized helper nodes for data manipulation

Grid-based interoperability of workflow systems

Calling Grid Services vs Web Services Call Grid Service Call Grid Service Call Grid Service Remote Grid Service

Example: Using of GRIA services GRIA uses a fully decentralized management approach, with minimal dependency between sites. Each site offering GRIA services makes its own business decisions about which users to trust and on what terms, and is responsible for enforcing its own access policies and deciding which applications to support. Sites can interact with each other, but this is driven by their common consumers, and those consumers are responsible for managing the resulting dependencies. There are no global agreements to set up, and no virtual organizations need be established, though users can interact according to virtual organization models if they want.

Example: Pharma application Five basic Sub-workflow nodes 1.Allocate Resources 2.Upload Inputs 3.Execute 4.Retrieve Result 5.Finish Conversation

Grid-based workflows and interoperability Run-time interoperability –Workflow-based applications as services –Workflow enactment as services

Method 1: Workflow-based application as service

Example: Aero application

Method 2: Workflow enactment engine as service

Interoperability interaction patterns (a) Chained Process Model(b) Nested Sub-process Model (c) Parallel Synchronized Model(d) Polling Synchronized Model

Current Status

Next Steps: Moving from abstract to heterogeneous executable workflows

Overall approach User specifies high-level steps Steps iteratively instantiated using services and workflow templates Use service registries and workflow warehouses Use existing run-time interoperability mechanisms

Architecture Heterogeneous workflow warehouse –InforSense Workflow warehouse Service Registries –NEC Semantic Broker Authoring advisor: high-level steps for application domains Authoring assistant: map from abstract tasks to workflow fragments and services

Workflow warehousing and mining

Summary Using industrial strength workflow systems for cross-organization product design Run-time interoperability mechanisms Supporting the design of heterogeneous workflows