Adding Semantic to Web Servicesbeaune/websem/cours2008_2009/... · D1 - 15/01/2009 The present document contains information proprietary to France Telecom. Accepting this document

D1 - 15/01/2009The present document contains information proprietary to France Telecom. Accepting this document means for its recipient he or she recognizes the confidential nature of its content and his or her engagement not to reproduce it, not to transmit it to a third party, not to reveal its content and not to use it for commercial purposes without previous FTR&D written consent.

Adding Semantic to Web ServicesA tour on Foundations et Applications

Doctoral School, St Etienne January 2008

Alain Léger FT R&D Orange Labs ResearchDR Knowledge Processing

Co-Manager Industry Area NoE KnowledgewebFreddy Lécué FT R&D Orange Labs Research3rd year PhD


From distributed object and applications to Web Services

KnowledgeWeb

Acknowledgements and Thanks to various people from whom I “borrowed” material : Katia Sycara, Michael Stollberg, Dumitru Roman, John Domingue, Christophe Rey, Amit Sheth, Carlo Ghezzi, ...

And thanks to all the people from whom they borrowed it ☺

France Télécom R&D Diffusion of this document is subject to the autorisation of France Télécom R&DD3 - 15/01/2009

Cours Web Services sémantiques © Alain Léger FT R&D, ENS M SE St Etienne, 5-14 January 2009

Télécom : Intégration ressources hétérogènes

Where the latestfilm from CleantEastwood visible

In the town tonight?Critics and video

clips?

MediationsPlateforme Agile de services distants et dynamiques

Réduit les coûts et temps d'intégration

Vorei il sommario in italiano di questa guida turistica. Grazie

Hi Dear Customer,Your problem …

and will be resolvedin the next 2 hours

by our technicalteam



Inte

grat

ion

Busi

ness

Pro

cess

Services Web Semantique : L' Intégration par composition automatique ?

sChaque tâche a un

but

sLe service le plus

approprié pour

atteindre un but est

localisé soit à design-

time ou à run-time.

sHétérogénéité des

données et protocoles

est traités par des

médiateurs

Serv

ices

Buyer

Sales Department Factory

(supplier) Risk & Financials

3rd Party Shipment

Mediator Mediator

LegacyMediator

Mediator Comm.Mediator

Mediator MediatorMediator

MediatorMediatorLegacyMediator

Mediator

LegacyMediator

Mediator

MediatorMediator Comm.MediatorComm.

MediatorMediatorMediator

SSemanticallyemantically EEmpoweredmpowered SServiceervice OrientedOriented AArchitecturerchitecture

(c) CEFRIEL – Politecnico di Milano



Grandes étapes de l’intégration

Très fort

Faible

MiddlewareBut : définir des abstractions pour concevoir des

applications distribuées

Enterprise Application Integration (EAI)

But : Intégrer des middleware, en plus des systèmes classiques

Inter-EAIBut : comme EAI, mais avec internet comme

voie d’accès principale

Service-Oriented Architecture (SOA)

Ppe : exposer les processus métiers comme des services réutilisables en environnement faiblement couplé (par ex. B2B entre partenaires du Web)

But : conception, développement, intégration orientés services

Couplage

Fort

Fort

ContexteUne même entreprise,un même

départementLAN

Plusieurs départements d’une même entreprise

LAN

Entreprisesen partenariat

étroitLAN et Internet

Plusieurs entreprisessur le Web

LAN et Internet

Homogènes :fonctionnalités similaires,architecture centralisée,communications synchrones,fine granularité d’échange

Hétérogènes :fonctionnalités différentes,architecture centralisée,communications asynchrones,grande granularité d’échange

Très hétérogènes :fonctionnalités très différentes,architecture décentralisée,communications asynchrones,granularité d’échange variable

Systèmes reliés TechnologiesRPCTP monitors(CICS, MTS, Tuxedo)

Obect brokers(CORBA)

Message brokers(WebSphere MQ, WebLogicIntegration)

Workflow MS(Biztalk)

Application servers(J2EE, .NET)

Services Web

???

Web Services: Concepts, Architectures and Applications; Gustavo Alonso et al.



Vers l’intégration idéale

s Avantages du couplage fortQBien savoir ce qu’on fait et comment le faireQConfianceQPerformances et robustesse

s Avantages du couplage faible induit par le webQOffre importante, sans cesse renouvelée et mise à jourQPossibilité de changer facilement et rapidement de partenairesQPour toutes les entreprises :

– Moins coûteux (temps, hommes, argent)– Moins contraignant

s Dans une architecture décentraliséeQPour s’affranchir des contraintes d’un middleware centraliséQRépartir la chargeQDéveloppement décentralisé, réutiliser les composants disponibles

s En automatisant le plus possibleQRéduction des coûtsQPassage à l’échelleQAdapté au caractère dynamique du Web



Usage 1 : wrapper

resource manager

resource manager

middleware

service interface

integration logic

middleware

service interface

integration logic

other tiers

resource manager

resource manager

middleware

service interface

integration logic

s Conversion des messages sous

divers formats

s Grosse granularité sinon surcoût

Web Services : Alonso, Casati, Kuno, Machiraju Copyright Springer Verlag Berlin Heidelberg 2004

Intermédiaire d’intégration



Usage 2 : intégration statique

s Encapsuler des applications hétérogènes (via un LAN, ou internet)

service providerservice requestor

application object(client)

application object(service provider)

SOAP-based middleware

SOAP-based middleware

SOAP messages exchanged on top of, HTTP, SMTP, or other transport

converts procedure calls

to/from XML messages sent

through HTTP or other protocols.

Web Services : Alonso, Casati, Kuno, Machiraju Copyright Springer Verlag Berlin Heidelberg 2004

Très pratique car simple et rapide



Strong Evolution not a revolution

s Gluing software becoming dominantQDistinction between components and connectorsQWrappers for componentsQMiddleware provides binding mechanisms

– Middleware as a decoupling layer– separation of concerns

s Development transitionQFrom software developed by a single organization (or by collaborating organizations)QTo components developed by independent organizations with different degrees of contractual obligations

s Where we are movingQUnprecedented levels of change

– business level– process level– product level

QRequirements for unanticipated changeNew challenges for New challenges for swsw

engineering!engineering!



bodyencapsulatesmodifiable

design choices

interfacevisible to clients

volatile

stable

Design for change



Where are the sources of change?

s Changes originate in the business world

Qagile networked organizations

Qfast organizational responses to rapidly changing requirements

– intra and extra organization changes require continuous changes in the information

system

Qmodernizing legacy systems

s Changes originate in the interaction with the physical environment

s Implied by pervasive/ubiquitous computing requirements

Qmobility and context awareness

Qambient intelligence and disappearing computer

– external world changes unpredictably

–because context changes

–because new active objects are encountered



The "SoC approach"

s Service-oriented business, process and product architecture to support Qdynamic, goal-oriented, opportunistic federations of organizations

Qrapidly adapting to changing requirements

s Support active objects providing service, such asQtaggable objects (RFID)

Qsensors and sensor networks

s Ability to deal with context changes and unanticipated events and

changesQself-adapting, self-healing, self-organizing behaviors


Service-Oriented Computing

Viewed as a set of concepts and technologies targeting these problems

Where are the new challenges?

Keynote Carlo GhezziDEI—Politecnico di Milano, ICSOC 2005, Amsterdam



Services

specifiedspecified

publishedpublished

discovereddiscovered

negotiatednegotiatedcomposedcomposed

delivereddelivered

monitoredmonitored



Challenge 1: Specification

s Services should be specified by the contract they will fulfill for their clients

Qcontract must state QoS

– not just a syntactic interface

– not just functional behavior

s Specifications must be publishable and discoverable



Challenge 2: Composition

s Services should be composable, and (in turn) composite services should be composable

Qhow is the contract of a composite service derived from its

constituents?

s Compositions may require negotiation

s Different binding regimes should be possible, from static and pre-runtime to late&dynamic



Challenge 3: Trust, verification

s Services are developed and run in their own domains

Qno control over them, no access to the internals

Qhow can we trust a service contract?

s They may change without notice

Qdoes the change affect us?

Qhow can trusted services be provided out of untrusted components?

s Late binding adds flexibility at the expense of reduced safety

s We are moving from the safety of pre run-time structuring&verification to the complete freedom of dynamic composition, while we are providing service

Qwe need to go beyond traditional pre run-time testing and validation!



Challenge 4: Evolution

s Compositions change to support evolution

QHow can evolution be supported dynamically?

– result of detected deviation from expected QoS

– result of environment/unanticipated change

QContinuous evolution to achieve QoS optimizations?

QTowards self-organizing behaviors?



Composition dimensions

time (binding regime)time (binding regime)

compilecompile--timetime

deploydeploy--timetime

runrun--timetime

changechangereq.mtsreq.mtsnono

changechangeanticipatedanticipatedchangechange

unanticipatedunanticipatedchangechangeselfself--organizationorganization



Vers les SOA et Les services Web (WS>>SOA>>SOC)

s Objectif : transition inter-EAI SOA (en douceur)

QAller au-delà des limites de l’intégration telle qu’elle se fait actuellement dans

les EAI– Grand coût de mise en œuvre : temps, hommes argent reservé aux grandes entreprises

– Architecture centralisée : problème de confiance entre partenaires : qui héberge le système ?

QEn posant les bases des SOA

s Méthode :

QCentralisé décentralisé

QFort couplage faible couplage

objectif : pouvoir utiliser le Web et se grande offre de services sans cesse remise à jour,

pouvoir changer facilement de partenaires, …



Static WWWURI, HTML, HTTP

The Web Vision : towards Web Services

Q500 million users Qmore than 3 billion pages



WWWURI, HTML, HTTP

Semantic WebRDF, RDF(S), OWL

Dynamic Web ServicesUDDI, WSDL, SOAP

Static

Semantic WebServices

Bringing the web to its full potential

The Web Vision : towards automated Web



The Intelligence is in the Connections

From Nova Spivack, http://www.mindingtheplanet.net Connections between people

Con

nect

ions

bet

wee

n In

form

atio

n

Email

Social Networking

Groupware

JavascriptWeblogs

Databases

File Systems

HTTPKeyword Search

USENET

Wikis

Websites

Directory Portals

2010 - 2020

Web 1.0

2000 - 2010

1990 - 2000

PC Era1980 - 1990

RSS Widgets

PC’s

2020 - 2030

Office 2.0

XML

RDF

SPARQLAJAX

FTP IRC

SOAP

Mashups

File Servers

Social Media Sharing

Lightweight Collaboration

ATOM

Web 3.0

Web 4.0

Semantic SearchSemantic Databases

Intelligent personal agents

JavaSaaS

Web 2.0 Flash

OWL

HTML

SGML

SQLGopher

P2P

The Web

The PC

Windows

MacOS

SWRL

OpenID

BBS

MMO’s

VR

Semantic Web

Intelligent Web

The Internet

Social Web

Web OS



Web Services

s loosely coupled, reusable components

sencapsulate discrete functionality

sdistributed

sprogrammatically accessible over standard internet protocols

sadd new level of functionality on top of the current web



The Promise of Web Services

web-based SOA as new system design paradigm



WSDL

s Web Service Description Language

s W3C effort, WSDL 2 final construction phase

Describes interface for consuming a Web Service:- Interface: operations (in- & output) - Access (protocol binding) - Endpoint (location of service)

http://www.w3.org/TR/wsdl



UDDI

s Universal Description, Discovery, and Integration Protocol

s OASIS driven standardization effort

Registry for Web Services:- provider - service information- technical access

http://www.oasis-open.org/committees/uddi-spec/doc/tcspecs.htm



SOAP

sSimple Object Access Protocol

sW3C Recommendation

XML data transport:- sender / receiver- protocol binding- communication aspects- content

http://www.w3.org/TR/2003/REC-soap12-part0-20030624/



Lacks of Web Service Technology

s current technologies allow usage of Web Services

sbut:Q only syntactical information descriptions

Q syntactic support for discovery, composition and execution

=> Web Service usability, usage, and integration needs to be inspected manually

Q no semantically marked up content / services

Q no support for the Semantic Web

Q=>Current Web Service Technology Stack failed to

realize the promise of Web Services



Semantic Web Technology

+

Web Service Technology

Semantic Web Services

=>

• allow machine supported data interpretation• ontologies as data model

automated discovery, selection, composition, and web-based execution of services

Semantic Web Services as integrated solution for realizing the vision

of the next generation of the Web




sdefine exhaustive description frameworks for describing Web Services and related aspects (Web Service Description Ontologies)

s support ontologies as underlying data model to allow machine supported data interpretation (Semantic Web aspect)

sdefine semantically driven technologies for automation of the Web Service usage process (Web Service aspect)




Usage Process:

s Publication: Make available the description of the capability of a service

s Discovery: Locate different services suitable for a given task

s Selection: Choose the most appropriate services among the available ones

s Composition: Combine services to achieve a goal

s Mediation: Solve mismatches (data, protocol, process) among the combined

s Execution: Invoke services following programmatic conventions




Execution support:

s Monitoring: Control the execution process

s Compensation: Provide transactional support and undo or mitigate unwanted effects

s Replacement: Facilitate the substitution of services by equivalent ones

s Auditing: Verify that service execution occurred in the expected way



Service Oriented Architecture

Intergiciels

Histoire de la programmation

Langages de programmation

Composants

Langage d'intergicielInterface composantComportement compositionnelMonde ouvert (OWA)Langages Corba / IDL, DCOM

1990

Services

Langage "Business Rules"Interface service SA-WSDLComportements formels réactifsMonde ouvert (OWA) et WebNormes, Langages déclaratifs et procéduraux 2000

Actes de Langage (ACL, KQML)Comportement autonome, proactif, cognitif, apprenant et coopératifMonde ouvert (OWA)Langages déclaratifs et procéduraux (KIF, PROLOG, Java)

Agents ?

1990

Structurée

1970

Objets

Langage compiléInterface objet/méthodesComportement explicite dans l'objetMonde fermé (CWA)Langages SmalTalk, C++, Java

1980

Langage compiléInterface appel de fonctionsDonnées et FonctionsLangages Fortran, ADA, PL1, Cobol



Web Services: The Big Questions

Simplify and/or automate web service

sDiscoveryQWhat properties should be described?QHow to efficiently query against them?

sCompositionQSpecifying goals of a compositionQSpecifying constraints on a compositionQBuilding a composition QAnalysis of compositions

s InvocationQKeeping enactments separatedQProviding transactional guarantees

sMonitoringQHow to track enactmentsQRecovering from failed enactments

Primary focusof this tutorial



SOAP

WS-Choreography

Web Services Standards Stack: Key Elements

Network

PayloadMessaging

(Individual)Service

Description

Composition

Choreography

Discovery

HTTP, SMTP, FTP, etc.

UDDI

OWL-S ServiceProfile

WSCL

WSDL

BPEL4WS OWL-S ServiceModel

Focus on some aspects of these

standards


Cours Web Services sémantiques © Alain Léger FT R&D, ENS M SE St Etienne, 5-14 January 2009 37

Background

• Semantic Web Services• Semantic descriptions of services• Late-Binding – semi-automated binding of requester‘s goal and

services• Includes discovery, selection, composition, ... mediation, ...

• Invocation – invocation of „bound“ services to consume the servicefunctionality• Includes conversation and mediation

• Service Discovery• Two stages:

• Web Service Discovery (abstract level) – operates on abstractdescription of a goal and a service

• Service Discovery (instance-level) – elaborates on results fromabstract level and takes into account input data



Selection

38

Exemplary scenario

I want to buy 2 cheap IBM T60p laptops and ship them to GalwayI want to buy 2 cheap IBM T60p laptops and ship them to Galway

Mueller Service

I am selling and shipping computers (publish service description)

I am selling and shipping computers (publish service description)

Web ServiceDiscovery

ServiceDiscovery

May be Mueller can do itMay be Mueller can do it

Do you have 2 IBM T60p and for how much?Do you have 2 IBM T60p and for how much?

Do you ship to Galway and for how much?Do you ship to Galway and for how much?

Mueller can do itMueller can do it

E-Hub

yes, 1300€

yes, 100€



Objectives

• Service Discovery• Data needed: user data and service data• User Data is either part of user goal request or can be

supplied through user‘s interactions• Service Data: need to be supplied thorugh service

dynamically• Questions (we only care about service data)

(1) Which service data to supply for discovery(2) How to supply the service data for discovery



Objectives

• Which service data to supply for discovery?• modeling of service „data-fetching“ interface

• How to supply the service data for discovery?• invocaction of the service „data-fetching“ interface as part

of the discovery process



Modeling of Service „data-fetching“ interface

• Choreography (service view): all input messages are sentfrom the network and all output messages are sent to thenetwork

• State Machine• ontology conpcets as input/output messages

• Data-fetching interface is part of service description createdby the service provider• Service provider decides on which data can be fetched• Data-fetching interface defines meta-interactions with the

service



Service Interface and Grounding to WSDL

WebService

Choreography and Grounding Definition

WSDL Web Service Operations, Input and output messages

ab

Input/output conceptsin a → grounding to a WSDL operation’s message out b → grounding to a WSDL operation‘s message

…Transition Rules

If a then add(b)…

State Machine Rules

If message A is available thenadd message B throughfrom invocation of related operation.



Road Map



Hype curve for XML Technology 2006

Users and Vendors alike will see opportunities to exploit maturing XML technologies. It is important to understand less mature technologies as well,

to anticipate how they could simplify work processes, reduce costs or improve interactions with other entitiesin your enterprise "ecosystem"

— be it a supplier, partner, regulatory agency or customer. Sometechnologies may evolve into enabling a new computing foundation

that will change everything in IT — products, providers, governance and organizations. Familiarity should not determine what technologies are watched; business impact should !

Gartner, July 2006 "Hype cycle for XML Technologies, 2006



Hype Cycle Curve of SW-related Topics from the Researchers' Point of View



KWeb NoE Perspective vs/ Gartner’s References



SWOT



Macro Roadmap for Semantic Web Services in a priority matrix



Etat de l'art Industrie et grands défis en SWS

Etat de l'Art Grands Défis

Service Foundations

Enterprise Service BussOpen standard message backbone (SOAP)sCurrent industry ESB-SOA (BEA, IBM, SUN, Microsoft, SAP)sSemantic Execution environment OASISsOntology alignmentsSOA Reference Model OASIS

Dynamically (re)configurable run-time architectureDynamic connectivity capabilitiesTopic and content based routing capabilities

Mediation facilities for data, message schemas, flows and process integration

Servicesfacilities

Semantic integration (EAI ++) : few deployed on small scales (Semagix, Ontoprise-Software AG, Contivo, WebMethods/Cerebra, …)Service discovery at the syntax matching level (UDDI) - many solutions in labsService composition still ad-hoc and manual (EAI style) - many solutions in labs Services orchestration manually generated (BPEL)Semantic web Services pilot platform

Automated and accurate – Functional and Behavioural Service discovery Non-functional parameters (QoS) aware compositionBusiness driven (SLA) compositionOrchestration generation automated End-to-end security and transaction solutionsKRR grand challenges : scale-up to large, ontologies and annotations of real life needs, reasoning under uncertainty and inconsistencies, KR and Query and process languages finalized, expressivity vs complexity mastered for industry, matching and reasoning in P2P, Ontology learning and maintenance

Service management

Management of Web ServicesWeb services based managementWeb service distributed management

Vérification des politiques de sécurité et propriétés transactionnelles du schéma d'orchestration.Systèmes auto-guérisssants, Auto-configuration dynamique,Auto-optimisation, Auto-protection

Service Engineering

Port existing components using wrappersComponent and OO analysis and designTools include basic web service description (WSDL) (BEA, IBM, SUN, Microsoft, SAP)Few tools include advance Web services features (OWLS, WSML, SAWSDL)

CAD tools for semantic service engineering- Associating standard software development and business process modelling techniques - Automated Service Description- Make complexity very simple to use for practitioners

NoE KWeb extended version of NoE S-Cube Service Road Map [Papazoglou et al., 2006]



Knowledge Web Industry’s Vision on the State of the Art and Grand Challenges in Semantic Web Service research (1)









Etat de l'art Industrie et grands défis en SWS

Etat de l'Art Grands Défis

Service Foundations

Enterprise Service BussOpen standard message backbone (SOAP)sCurrent industry ESB-SOA (BEA, IBM, SUN, Microsoft, SAP)sSemantic Execution environment OASISsOntology alignmentsSOA Reference Model OASIS

Dynamically (re)configurable run-time architectureDynamic connectivity capabilitiesTopic and content based routing capabilities

Mediation facilities for data, message schemas, flows and process integration

Servicesfacilities

Semantic integration (EAI ++) : few deployed on small scales (Semagix, Ontoprise-Software AG, Contivo, WebMethods/Cerebra, …)Service discovery at the syntax matching level (UDDI) - many solutions in labsService composition still ad-hoc and manual (EAI style) - many solutions in labs Services orchestration manually generated (BPEL)Semantic web Services pilot platform

Automated and accurate – Functional and Behavioural Service discovery Non-functional parameters (QoS) aware compositionBusiness driven (SLA) compositionOrchestration generation automated End-to-end security and transaction solutionsKRR grand challenges : scale-up to large, ontologies and annotations of real life needs, reasoning under uncertainty and inconsistencies, KR and Query and process languages finalized, expressivity vs complexity mastered for industry, matching and reasoning in P2P, Ontology learning and maintenance

Service management

Management of Web ServicesWeb services based managementWeb service distributed management

Vérification des politiques de sécurité et propriétés transactionnelles du schéma d'orchestration.Systèmes auto-guérisssants, Auto-configuration dynamique,Auto-optimisation, Auto-protection

Service Engineering

Port existing components using wrappersComponent and OO analysis and designTools include basic web service description (WSDL) (BEA, IBM, SUN, Microsoft, SAP)Few tools include advance Web services features (OWLS, WSML, SAWSDL)

CAD tools for semantic service engineering- Associating standard software development and business process modelling techniques - Automated Service Description- Make complexity very simple to use for practitioners

NoE KWeb extended version of NoE S-Cube Service Road Map [Papazoglou et al., 2006]



Recommandations

s Lire Web Services Concepts, Architectures and

Applications, Gustavo Alonso, Fabio Casati, Harumi

Kuno, Vijay MachirajuSpringer Verlag 2004, ISBN 3-540-

44008-9

Documents

Adding Semantic to Web Servicesbeaune/websem/cours2008_2009/... · D1 - 15/01/2009 The present document contains information proprietary to France Telecom. Accepting this document