1. © DATAMAT S.p.A. – 2007 1 Giuseppe Avellino, Stefano Beco, Barbara Cantalupo, Andrea Cavallini A Semantic Workflow Authoring Tool for Programming Grids Workflows in Support of Large-Scale Science Workshop 23th June 2007

2. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 2 - Outline NextGRID Project Workflow Programming Model Workflow Language Requirements Semantic Workflow Landscape OWL-WS Ontology Language Semantic Workflow Programming Tool (SWPT) Conclusions Future Plans

3. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 3 - NextGRID Project This work is part of NextGRID project, an FP6 EU Funded Project The objective is to define a Next Generation Grid (NGG) architecture This work is in the context of dynamic aspects of Grid systems: how services and clients interact to enable federation of resources, services and users between disparate domains Grid Virtual Infrastructure Model (Grid VIM)  Makes the Grid infrastructure adaptable to the needs of different actors  Provides a consistent interface for application developers and users

4. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 4 - Workflow Programming Model Workflows play an important role in the process of turning from the Grid technology infrastructure to the Business Process Management environment Workflows can be considered as a Programming Model for service components composition and can support process flexibility by soft-coding application behaviour Representation of the interactions between software components and people in a business process is best done in terms of workflows

5. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 5 - Workflow Life-cycle Application User Application Developer Service Provider Procurement Manager Budget Holder Editing Application Workflow Editing Procurement Business Workflow Editing Provision Business Workflow Execute Application Execute Provision Process Service Manager Deploy Service with Workflows Define Application Execute Procurement Process > Authoring Enactment Publication ISV Provider Consumer

6. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 6 - Workflow Language Requirements Abstract workflows definition: abstract workflow composition possible without specifying a grounding (run-time grounding) Semantic task description: each task has a description or type/function Workflow substitution: a grounding could be a workflow itself Higher-order workflows management: a task can take a workflow as input and return another workflow for execution

7. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 7 - Semantic Workflow Landscape Formal Models Grid Architecture Workflow Semantics UML, BPMN,... WSDL. BPEL4WS,... Petri Nets, Pi Calculus, Turing Machine,... SAWSDL.... OWL-S, WSMO, WSDL-S, SWSF.... Grid Projects Web Services WSRF Business Models Business Process Management WS-CDL WSBPEL eBXML XPDL Workflow Patterns

8. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 8 - Semantic Workflow Landscape There are a lot of semantic workflow research fields which can provide some different solutions for specific needs We chose to extend OWL-S because we focused on semantic (innovative aspects) We also consider the possibility of BPEL + semantic, but BPEL had not Abstract Processes and was quite complicated We were looking for a simpler solution We also focused on defining something general, a Semantic Model, to investigate the semantic field and apply results also to other technologies and languages

9. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 9 - OWL-WS Ontology Language OWL-WS (OWL for Workflows and Services) is an extension of the OWL-S language OWL-WS  satisfies the workflow language requirements  extends the concept of Service to Abstract Process  uses the OWL-S Composite Process concept for workflow modelling  allows to assign a Profile to any Process OWL-S was proposed as a standard

10. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 10 - Semantic Workflow Programming Tool The SWPT is a graphical framework to model and edit semantic workflow in different application domains The SWPT is modular and designed on the base of the Reference Workflow Model It is designed to be as much as possible language independent It enables multiple business roles: application developer, end user, end users’ procurement authority and service provider It provides interface to Grid Infrastructure Services (Service Discovery, VO and SLA management, Security, etc)

11. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 11 - Semantic Workflow Programming Tool Framework The framework is composed of the following components:  Workflow Model Management Framework The core of the SWPT, it implements the internal workflow programming model, I/O, graphical and language interface  Authoring Framework GUI for workflow editing, validation and external interaction  Semantic Framework It provides tools and APIs for managing ontology  Deployment Framework Services publication  Workflow Representation Framework Interface external enactment system

12. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 12 - Semantic Workflow Programming Tool Framework Workflow Model Management Framework Authoring Framework Workflow Representation Framework Grid VIM / Target Enactment Systems Interface Framework Deployment Framework Semantic Framework Interface (API) Shared Components Tool + API for Ontology Management Editing Validation External Interaction

13. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 13 - Service is the basic workflow component  A Semantic Grid Service is defined and managed using some kind of semantic information Self-Similarity  Service and Workflows are similar entities from different level perspective Abstraction  Services can be described as Abstract or Concrete Workflow Model Management Framework A Service is a very Simple Workflow A Workflow can be exposed as a Service

14. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 14 - Workflow Model Management Framework Properties (Profile information - functionality)  Functional Input, Output, Precondition, Result  Non Functional (semantic) Constraint is information on required properties of the services Capability is information on the properties provided by the service Process (Process information – structure)  Control Flow, Data Flow, Events Execution  Implementation info (Service endpoint)

15. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 15 - Semantic Framework The Semantic framework enables users accessing information on the specific application or business domain Knowledge management is complex and it makes sense if the form it is represented is commonly understood Each domain can be described by ontology with a shared vocabulary and a set of task templates A task template is a service or a workflow that describes a function, inputs, outputs, parameters and semantic information

16. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 16 - Authoring Framework Authoring phases:  Ability to retrieve definition of services in a specific domain  Ability to compose selected services in workflows, providing information on data and control structure  Ability to specify additional information for each service or workflow Abstract services/workflows can be used to compose more complex workflows

17. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 17 - SWPT GUI

18. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 18 - SWPT GUI

19. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 19 - Conclusions We presented a Semantic Workflow Programming Model The language adopted is OWL-WS, but also other languages could be supported Looking at the past and future languages evolution, the SWPT language independence is of great value Final release of the tool in NextGRID context will be provided at the end of the year

20. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 20 - Future Plans New parsers could be developed in order to support new languages The tool is now integrated with the VIM to provide enactment and monitoring of the workflow, but other enactment systems are possible We are working on improving the workflow execution monitoring The tool will be also used in the context of the EU Brein project, and enhancements will be provided

21. WORKS07, Monterey 2007 © DATAMAT S.p.A. – 2007- 21 - References and Contacts This work has been supported by the NextGRID project (contract number 511563), which is co- funded by the European Commission's IST programme of the 6th Framework Programme  http://www.nextgrid.org/ http://www.nextgrid.org/ Contacts  {giuseppe.avellino, stefano.beco, barbara.cantalupo, andrea.cavallini}@elsagdatamat.com Thank you!