Semantic Web Enabled Web Services:Semantic Web Enabled Web Services:State-of-Art and Industrial ChallengesState-of-Art and Industrial Challenges

Vagan Terziyan, Oleksandr Kononenko

“Industrial Ontologies” Group

http://www.cs.jyu.fi/ai/OntoGroup/index.htm

Industrial Ontologies GroupIndustrial Ontologies Group

Int. Conference on Web Services Europe (ICWS-Europe’03), Erfurt, Germany, Sept. 23-25, 2003These slides are available from: http://www.cs.jyu.fi/ai/ICWS-2003.ppt

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Industrial Ontologies GroupIndustrial Ontologies Group

We develop Semantic Web solutions for industry– Our research contacts with: Metso, Tietoenator, Sonera, Nokia, …

Location: – University of Jyväskylä, Finland; – National University of Radioelectronics, Ukraine

Developed Concepts:– OntoServ.Net:

• Semantic Web-based large-scale automated industrial service integration framework for asset management (case of smart-devices maintenance is under development)

– GUN (Global Understanding eNvironment):• Approach for resource integration built using combination of Semantic Web,

Web Services and Agent technologies– OntoShell:

• Agent-based representative of informational entities in semantic-enabled environment (OntoServ.Net)

– OntoAdapter:• Connector-software that adapts native service interface to OntoServ.Net

find more details at www.cs.jyu.fi/ai/OntoGroup/

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Web Services and SemanticsWeb Services and Semantics

SWWS – Web Services with semantics represented explicitly via ontology-based descriptions

Intelligent agents will use semantic web services, discovering composing them accordingly their goals– New types of service consumers: user agents, devices, AI agents

– Intelligent dynamic service integration Reasoning about service capabilities requires more advanced service

description framework than existing technology has

The promise is that Web Service Technology in conjunction with Semantic Web Technology (“Semantic Web Services”) will make service integration dynamically possible for all types and sizes of environments compared to the “traditional” technologies

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Semantic Web support for IT Semantic Web support for IT

“The Semantic Web is a vision: the idea of

having data on the Web defined and linked

in a way that it can be used by machines

not just for display purposes,

but for automation, integration and reuse

of data across various applications”

http://www.w3.org/sw/

The Semantic Web is an initiative with the goal of extending the current Web and facilitating Web automation, universally accessible web resources, and the 'Web of Trust', providing a universally accessible platform that allows data to be shared and processed by automated tools as well as by people.

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SWWS main challenges (Dieter Fensel)SWWS main challenges (Dieter Fensel)

Service description Service discovery Service mediation

Web TechnologyHTTP, URI

Web ServicesUDDI, WSDL, SOAP

Semantic WebXML, RDF(S), OWL

Intelligent Web Services

Interoperability, knowledge management

E-commerce, EAI

Human-oriented data Machine-processable data

“Next-generation Web”

Dynamic

Static

Dimension Existing SWWS

Services Simple ComposableRequestor Human (developer) AgentProvider Registration No registrationMediator Key Player FacilitatorDescription Taxonomy OntologyDescriptiveness Closed world Open worldRepresentation Syntax-based Semantics-based

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UDDI needs semantics!UDDI needs semantics!

Service semantics Service interface semantics Message semantics and more..

Service model Constraints Composition rules

Domain ontologies

E-Market

E A I

Business Processes

Industrial Services

DA

ML-

S

DAML-S is an upper-ontology forservice description. Development of common domain ontologies will provide basis for semantic-enabled service descriptions.

Will be there a Semantic UDDI?Will be there a Semantic UDDI?

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Service descriptionService description

Description models in:WSDL, UDDI, E-Speak, ebXML, RosettaNet

BPEL4WS, WSCI, BPML

Existing technology:– No explicitly defined semantics in service descriptions– None of existing model proposes something more than basic ontology

definition– Keyword-based search is not enough

Semantic Web for Web Services:– Standards via ontological definition– DAML-S (upper ontology of services)

• Reuses WSDL adding semantics-binding elements• Provides ontological description of service model• Adds semantic-bindings to service profile

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Service Flow

Orchestration, Choreography, Composition

Where are changes?Where are changes?

BPEL4WS, WSCI, BPML

Discovery

Description

Messaging

Networking

Semantic match Collaborative service-agents

Ontology-based standards

UDDI

SOAP and extensions: Transactions Security Routing, etc.

WSDL

HTTP, FTP,email, etc.

RDF Messaging

DAML-S:

Service Model Service Profile Service Grounding (WSDL)

Ontologies

instead of

language

standards

Agents can ‘understand’what, when and how to use

services

Common

and domain

ontologies

Still to be implemented

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DAML-S is ontology for service description based on Resource Description Framework and DAML+OIL ontology language

DAML-S– ServiceProfile

properties for automatic discovery (offered functionality, preconditions, inputs, outputs and effects of service invocation)

– ServiceModel process model for automated integration and invocation

– ServiceGrounding communication-level details (WSDL)

Descriptiveness of DAML-SDescriptiveness of DAML-S

Requirement Satisfied by

Flexibility and expressivenessRDF

Semi-structured data support

Categorization capabilities RDFS

Ability to express constraints DAML+OIL

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Smart-devices are becoming users of provided maintenance services.

Maintenance Service NetworkMaintenance Service Network

Agents acting as service components in the Maintenance Service Network have ability to learn during work improving services’ performance.

OntoServ.Net: “Semantic Web Enabled Network of Maintenance Services for Smart Devices”, Industrial Ontologies Group, March 2003,

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Semantic-enabled web services in Semantic-enabled web services in OntoServ.NetOntoServ.Net

We add semantic-enabled descriptions of services to facilitate:– automated discovery and use of services by smart-devices;– automated integration of services;– communication between heterogeneous services.

Maintenance PlatformSet of “service components”

Service PlatformSet of “service components”

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InteroperabilityInteroperability

Ontology A: Documents Ontology B: Research

A commitment to a common ontology is a guarantee of aconsistency and thus possibility of data (and knowledge) sharing

Common (shared) ontology

Ontology C: Services

System 1System 2

\\AgServ\vagan\InBCT_1.doc

V. Terziyan

A:Report

A:Location3.1: analysis

A:Subject

A:Author

Instance-ofSemantic Web

A:name

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Service discoveryService discovery

DAML-S service profiles Supporting domain ontologies Semantic match procedure

Requested Service profile:- service of class “Text Search Service” (subclass-of “Search Service”)- “Data Source” is “PDF File”

Input data:1: “URL Location” of “Data Source”2: “Search String”

Required result:1: “Occurrence position” of “Search String”

Service profile

Class: “PDF Search Service”(subclass-of “Text Search Service”)

Input:1: “Search String”2: “Case-sensitive Flag”3: “URL Location”

Output:1: “Page Number”2: “Occurrence position”

Semantic match

Ontology of service description

Common Ontologies

Data Source

Search StringURL String …

… …

……

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Service discovery in OntoServ.NetService discovery in OntoServ.Net

Peer-to-peer network of platforms for maintenance services

No centralized service registration Peer-to-peer semantic search based on service profiles Profile includes history of “service use efficiency”

Maintenance Centersand Maintenance Platforms

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Services as AgentsServices as Agents

Service (an agent) is a self-interested, autonomous, active, mobile(!!!) entity

If Service = Agent, than Service is mobile– Mobile code is carried by agent– Agent-shell for web services– Agent-shell as service adapter

Main strategies:

• Service composition via collaboration between agent- services• Service composition by “Service Manager” accordingly to specific goals of service platform

Mobility factors:• Security• Bandwidth• Time and other constraints

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Semantic adaptersSemantic adapters

• OntoServ.Net resources:– Services– Device– Human– Data repository

+ Semantic adapter = OntoServ.Net Service

Semantic-basedcommunication via standard protocols

(semantic queries, ontologically

described data)

OntoServ.Net service

Specific communication methods

Application Resource

OntoServ.Net service

Semantic adapter

Human, smart-device, application, service, algorithm…

Service profile and configuration

In OntoServ.Net common “language” is used between adapters allows mapping into and from internal service-specific protocols.

Implementation of generic semantic-adapter software is non-trivial task, but adapters for restricted class of services (for device data access, data retrieval from DB, alarm system notifications) are less challenging.

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Service composition in OntoServ.NetService composition in OntoServ.Net

System is composed accordingly to Task Ontology New services are requested from the network when needed Service’s diagnostic “experience” is concerned

Platform

Maintenance ManagerService

Diagnostic Services

Smart-devices

Task Ontology

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Ontology support for OntoServ.NetOntology support for OntoServ.Net Common intermediate language: Unambiguous agreed vocabulary and semantics - Service taxonomy - Maintenance domain

Data access

Data access servicesData access services

Diagnostics

Diagnostic servicesDiagnostic services

Maintenance activities

User AgentsUser Agents

Sharable diagnostic knowledge representation System configuration Semantic adapter configuration

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OntoServ.NetOntoServ.Net Challenges Challenges

New group of Web service users – smart industrialsmart industrial devices devices.

Semantic Web enabled servicesSemantic Web enabled services InternalInternal (embedded) and externalexternal (Web-based) serviceservice

platforms platforms. “Mobile Service ComponentMobile Service Component” concept supposes that any

service component can move, be executed and learn at any platform from the Service Network, including service requestor side.

Semantic Peer-to-PeerSemantic Peer-to-Peer concept for service network management assumes ontology-based decentralized service network management.

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ConclusionConclusion

• Traditional web service technology is able to address some of problems today. However, in combination with Semantic Web Web Services have the potential to address these needs much better

• Semantic WebSemantic Web it is a new contextcontext within which one should rethink and re-interpret his existing businesses, resources, services, technologies, processes, environments, products etc. to raise them to totally new level of performance…

• The OntoServ.Net concept of Distributed Maintenance Network can be a good pilot case to implement the benefits of Semantic Web and Web Services integrated framework.

------------------------------------------Contact: Vagan Terziyan vagan@it.jyu.fihttp://www.cs.jyu.fi/ai/vagan

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AcknowledgementsAcknowledgements

Agora Center (University of Jyvaskyla):Agora Center includes a network of good-quality research groups from various disciplines. These groups have numerous international contacts in their own research fields. Agora Center also coordinates and administrates research and development projects that are done in cooperation with different units of university, business life, public sector and other actors. The mutual vision is to develop future's knowledge society from the human point of view.

http://www.jyu.fi/agora-center/indexEng.html

InBCT Project (2000-2004):Innovations in Business, Communication and Technology

http://www.jyu.fi/agora-center/inbct.html