Towards Semantic Interoperability: In-depth Comparison of Two Approaches to Solving Semantic Web Service Challenge Mediation Tasks

Tomas Vitvar, Marco Brambillatomas.vitvar@deri.org, marco.brambilla@polimi.it

The 9th International Conference on Enterprise Information SystemsMadeira, Portugal, 2007

Maciej Zaremba, Tomas Vitvar, Matthew Moran, Marco Brambilla, Stefano Ceri, Dario Cerizza, Emanuele della Valle, Federico Facca, Christina Tziviskou

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Overview

• SWS Challenge Scenario

• DERI Solution – WSMO, WSML, WSMX

• Politecnico di Milano + CEFRIEL Solution – WebML, Glue

• Comparision and Conclusion

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Scenario

• Moon company wants to build B2B integration with Blue company• Blue – RosettaNet to be integrated with Moon back-end CRM and OMS

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Scenario: Blue RosettaNet

• Blue sends purchase order (customer id, and items to be ordered) and expects order confirmation with confirmation id• Blue uses RosettaNet Standard PIP3A4 for Purchase Orders

POC[confirmationID

PO[id, item1, item2, item3]

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Scenario: Moon Back-end Systems

• Internal customer id must be obtained from CRM system based on provided ID by Blue

• Order must be opened in OMS system• Individual items are placed in OMS • Order is closed in OMS

id

cid

openOrder

addItem*

closeOrder

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Scenario: Interoperability Problems

• Interoperability Problems:– Incompatible XML schemas for Blue’s and Moon’s messages– Incompatible processes of Blue’s and Moon’s systems

Id’

cid

openOrder

addItem*

closeOrder

POC[confirmationID

PO[id, item1, item2, item3]Data

Interoperability

Process

Interoperability

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Overview

• Mediation Scenario

• DERI Solution – WSMO, WSML, WSMX

• Politecnico di Milano + CEFRIEL Solution – WebML, Glue

• Comparision and Conclusion

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SWS: WSMO, WSML, WSMX

• Semantic Web Services in DERI– SWS: WSMO, WSML, WSML

• community Effort driven by DERI • EU FP6 and national funding

• Web Service Modelling…• … Ontology -> WSMO

– Conceptual model for SWS: goal, ontologies, mediators, services

• … Language -> WSML– Ontology Language for SWS– WSML Variants: WSML Core, WSML DL, WSML Rule, WSML Full

• … Execution Environment and Architecture -> WSMX– Middleware platform for SWS– Now in OASIS SEE TC

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Scenario: WSMX to Facilitate Integration

Modelling of information and

behaviour of standard

RosettaNet definitions

Modelling of information and

behaviour of proprietary

back-end systems

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Scenario: What to model

WSMO

Ontology

WSMO

Service

WSMO

Ontology

WSMO

Service

RosettaNet

PIP 3A4

CRM, OMS

systems

Grounding Grounding

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Scenario: Deploy Models and Ontology Mappings

WSMO

Ontology

WSMO

Service

WSMO

Ontology

WSMO

Service

RosettaNet

PIP 3A4

CRM, OMS

systems

mapping rules

Grounding Grounding

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RosettaNet

PIP 3A4

WSMO Ontology: Modelling of Information

Web

Service

XML Schema WSMO

OntologyLifting Schema Mapping

Lowering Schema Mapping

Lifting Rules in XSLT

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RosettaNet

PIP 3A4

WSMO Service: Modelling of Choreography, Grounding

Web

Service

WSMO Choreography and Grounding Definition

WSDL Web Service Operations,

Input and output messages

a

b

stateSignature

in a → wsdl.interfaceMessageReference …

out b → wsdl.interfaceMessageReference …

…transitionRules

If a then add(b)

…

Abstract State Machine Rules

If message A is in the memory, then

add message B to the memory

from invocation of related operation.

Conversation: Process and Data Mediation

Mapping RulesWSMO

Ontology

(Moon-CRM/OMS)

WSMO

Ontology

(Blue-PIP3A4)a ↔ o, b ↔ p, c ↔ q, d ↔ r

Data Mediator

Process Mediator

Choreography

Engine

blue

Send PO

Receive POC

GetCustomer

OpenOrder

AddItem

CloseOrder

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moon

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Overview

• Mediation Scenario

• DERI Solution – WSMO, WSML, WSMX

• Politecnico di Milano + CEFRIEL Solution – WebML, Glue

• Comparision and Conclusion

The WebML-SWEET framework

SWSWebMLS

eman

tic Web S

ervice

Ap

plicatio

n

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Model-driven design for WSMO

WSML

Goal

WSML WS

Choreography

WSML

WS Capability

WSML

Ontology

Ontology importing and/or semantic annotation

Automaticcode

generation

Businessprocess

modeling WF-driven

WebMLgenerator

Webapplicationmodeling

•

BPMN

model

WebML

skeleton

Running

application

WebML

Datamodel

WebMLhypertext

model

WSMLOntologyGenerator

WSMLWS Capabilty

Generator

WSMLWS Chor.Generator

WSMLGoal Cap.Generator

The SWE-ET is a top-down approach to the development of applications employing Semantic Web Services, that combines semantic methods and tools with Software Engineering ones.

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• Semantics-enabled data models @ participants (enriched E-R models vs. ontologies)

• Lowering and lifting implemented through XSLT transformations:– Participant model XML messages

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WebML Data Mediation

ebMLW

WebML-WSMO Choreography

Choreography interface of the service can be extracted from the description and registered in a Semantic Execution Environment (i.e. WSMX)

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ebMLW

WebML – WSMO capabilities

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Overview

• Mediation Scenario

• DERI Solution – WSMO, WSML, WSMX

• Politecnico di Milano + CEFRIEL Solution – WebML, Glue

• Comparision and Conclusion

Issue WebML/ WebRatio WSMO/ WSMX

Data modeling Enriched ER Ontologies

Data mediation XSLT-based mapping and lifting/ lowering

Design-time onto-onto mapping. Bidirectional XML-WSML lifting/lowering.

Process modeling BPMN/WebML of services and a mediator

Ontologized ASM of each service’s choreography

Process mediation

Execution of WebML mediator

Execution of service’s choreographies

Web services publishing and invocation

Generic units for publishing and invocation. AXIS

Services published on WSMX, invocation according to the grounding

Comparison

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• Two different approaches to semantic mediation– WebML: starting from a software engineering

background. Focus on design time– WSMO: starting from semantic web experience.

Focus on runtime dynamic integration

• Most explicit evidence– WebML: design-time process mediation model, based

on BPMN– WSMO: no design-time process mediation model;

runtime dynamic process mediation

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Conclusions

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Thanks!