david martin for daml-s coalition 05/08/2003 part ii: owl-s technical overview profile, process...

David Martin for DAML-S Coalition 05/08/2003

Part II: OWL-STechnical Overview

Profile, Process & Grounding ontologies Next Steps & Future Directions

SWSI, SWSL & SWSA


DAML-S Web Services CoalitionBBN: Mark Burstein

CMU: Katia Sycara, Massimo Paolucci*

ICSI: Srini Narayanan

Maryland / College Park: Bijan Parsia

Nokia: Ora Lassila

Stanford KSL: Sheila McIlraith*

SRI: David Martin*

Southampton: Terry Payne*

USC-ISI: Jerry Hobbs

Yale: Drew McDermott

*Contributor to these slides


What is OWL-S?

• Ontology Web Language for Services • An OWL ontology/language for (formally) describing properties and capabilities of Web services

• An approach that draws on many sources• Description logic• AI planning• Workflow• Formal process modeling• Agents• Web services

http://www.daml.org/services/


Layered Approach to Language Development

DAML-??? (Rules, FOL?)

XML (Extensible Markup Language)

RDF (Resource Description Framework)

RDFS (RDF Schema)

DAML+OIL OWL (Ontology)

OWL-S (Services)

OWL-S: a major application of OWLFuture versions will build upon emerging layers (e.g. DAML-Rules)


OWL-S ObjectivesAutomation of service use by software agents

Ideal: full-fledged use of services never before encountered:Discovery, selection, composition, invocation, monitoring, ..

Useful in the “real world”Compatible with industry standardsIncremental exploitation

Enable reasoning/planning about servicese.g., On-the-fly composition

Integrated use with information resourcesEase of use; powerful tools


Automation Enabled by OWL-S

• Web service discovery Find me a shipping service that transports goods to Dubai.

• Web service invocation Buy me 500 lbs. powdered milk from www.acmemoo.com

• Web service selection & composition

Arrange food for 500 people for 2 weeks in Dubai.

• Web service execution monitoring Has the powdered milk been ordered and paid for yet?


Pro

cess

Mod

el

Gro

undi

ng

Development … Deployment … Use …

Publication

Simulation

Verification

Discovery

Composition

Key:

Selection

Execution, Interoperation

Monitoring, Recovery

Pro

file


Upper Ontology of Services

Ontology images compliments of Terry Payne, University of Southampton


High-level characterization/summary of a serviceUsed for

• Populating service registries• A service can have many profiles

• Automated service discovery• Service selection (matchmaking)

One can derive:• Service advertisements• Service requests

Service Profile: “What does it do?”


Service ProfileNon Functional Non Functional PropertiesProperties

Functionality Functionality DescriptionDescription


Service Profile: Functionality Description

• Functional Specification of what the service provides in terms of parameters, subclassed as:– preconditionspreconditions– inputsinputs– outputsoutputs– effectseffects

• Summarizes the top-level Process


Service Profile: NonFunctional Properties

• Provides supporting information about the service.


Service Profile: NonFunctional Properties

• These include– serviceName

– textDescription

– qualityRating

– serviceParameter

– serviceCategory

– contactInformation


Service Profile: NonFunctional Properties - Actor


• Class-hierarchical yellow pages– Implicit capability characterization

– Arrangement of attributes on class hierarchy

– Can use multiple inheritance

– Relies primarily on “non-functional” properties

• Process summaries for planning purposes– More explicit

– Inputs, outputs, preconditions, effects

– Less reliance on formal hierarchical organization

– Summarizes process model specs

– Relies primarily on functional description

Service Profile: Styles of use


Exploiting Profile Hierarchies

Tie in with UDDI, UNSPSC, …

DL Basis for matchmaking

Multiple profiles; multiple taxonomies


Service Model“How does it work?”

Process– Interpretable description of service provider’s behavior– Tells service user how and when to interact (read/write

messages)& Process control

– Ontology of process state; supports status queries – (stubbed out at present)

• Used for:– Service invocation, planning/composition, interoperation,

monitoring • All processes have

– Inputs, outputs, preconditions and effects– Function/dataflow metaphor; action/process metaphor

• Composite processes– Control flow– Data flow

Process Model: “How does it work?”


Service Model / Process Model


Acme Book

Truck Shipment

Function/Dataflow Metaphor

Input:

• confirmation no.• ...

Output:

• failure notification• …

truck available+

valid credit card

Y

N?

• customer name• origin• destination• weight• pickup date• ...


AI-inspired Action/Process Metaphor

Input:


Output:


truck available+

valid credit card

Y

N?

Preconditions:

• customer name• origin• destination• pickup date• ...

• knowledge of the input• ...

• goods at location if successful• credit card debited...

Effect:

Output:

Effect: <no effect>

Acme Book

Truck Shipment


AcmeTruckShpng

www.acmeair.com

book flight service

• customer name• flight numbers• dates• credit card no.• • ...


• failure notification• errror information• …

?

www.acmehotel.com

book hotel service

• confirmation no.• dates• room type• credit card no.• ...



?

www.acmecar.com

book car service

• customer name• location• car type• dates• credit card no.• ...



?

• • • •

Composite Process

• • • • • • • • • •

• • • •

?

• • • • • • • • • • •

Input &Preconditions

Output &Effects

• • • •

• • • •


Atomic Process Example

<!– Atomic Process Definition - GetDesiredFlightDetails --> <rdfs:Class rdf:ID="GetDesiredFlightDetails"> <rdfs:subClassOf rdf:resource="http://www.daml.org/Process#AtomicProcess" /> </rdfs:Class>

GetDesired Flight Details

Airport

Flight Date

departureAirport_In

outboundDate_In

<!– (sample) Inputs used by atomic process GetDesiredFlightDetails --> <rdf:Property rdf:ID="departureAirport_In"> <rdfs:subPropertyOf rdf:resource="http://www.daml.org/Process#input" /> <rdfs:domain rdf:resource="#GetDesiredFlightDetails" /> <rdfs:range rdf:resource="http://www.daml.ri.cmu.edu/ont/

DAML-S/concepts.daml#Airport" /> </rdf:Property>

<rdf:Property rdf:ID="outbounDate_In"> <rdfs:subPropertyOf rdf:resource="http://www.daml.org/Process#input" /> <rdfs:domain rdf:resource="#GetDesiredFlightDetails" /> <rdfs:range rdf:resource="http://www.daml.ri.cmu.edu/ont/ DAML-S/concepts.daml#FlightDate" /> </rdf:Property>


Composite Process Example

<rdfs:Class rdf:ID="BookFlight"> <rdfs:subClassOf rdf:resource="#CompositeProcess" /> <rdfs:subClassOf rdf:resource="http://www.daml.org/Process#Sequence" /> <daml:subClassOf> <daml:Restriction> <daml:onProperty rdf:resource="http://www.daml.org/Process#components" /> <daml:toClass> <daml:subClassOf> <daml:unionOf rdf:parseType="daml:collection"> <rdfs:Class rdfs:about="#GetFlightDetails" /> <rdfs:Class rdfs:about="#GetContactDetails" /> <rdfs:Class rdfs:about="#ReserveFlight" /> <rdfs:Class rdfs:about="#ConfirmReservation" /> </daml:unionOf> </daml:subClassOf> </daml:toClass> </daml:Restriction> </daml:subClassOf></rdfs:Class>

Composite Process

Confirm Reservation

BookFlight

Get Contact Details

Sequence

Get Flight Details

Reserve Flight

SequenceSequence


Simple and Composite Processes

truck available+

valid credit card

Y

N

Confirm Shipping Region

Get Quote

Get Shipping Dates

Book Truck Shipment

Acme

Truck

Shipping

Service

expands

AcmeTruckShpng ExpandedAcmeTruckShpng


Service Grounding: “How to access it”

• Implementation-specific

• Message formatting, transport mechanisms, protocols, serializations of types

• Service Model + Grounding give everything needed for using the service

• Builds upon WSDL


OWL-S / WSDL Grounding

• Web Services Description Language– Authored by IBM, Ariba, Microsoft– Focus of W3C Web Services Description WG– Commercial momentum– Specifies message syntax accepted/generated

by communication ports– Bindings to popular message/transport

standards (SOAP, HTTP, MIME)– Abstract “types”; extensibility elements

• Complementary with OWL-S


OWL-S / WSDL Grounding

Resources/Concepts

WSDL

OWL-S

Process Model

Atomic Process

Operation Message

Inputs / Outputs

Binding to SOAP, HTTP, etc.


OWL-S / WSDL Grounding (cont’d)


daml-property

owl-s-process

inputX

daml-propertyoutputY

AtomicProcess

WSDLDocument

<message …> <part …>

<message …> <part …>

<operation …>

<binding …>

OWL-S / WSDL Grounding (cont’d)


Review: Upper Ontology of Services


Path of EvolutionRelease 0.5 (May 2001)

Initial Profile & Process ontologies

Release 0.6 (December 2001)Refinements to Profile & Process; Resources ontology

Release 0.7 (October 2002)Initial DAML-S/WSDL Grounding; Profile, Process Model refinements; more complete examples

Release 0.9 (May 2003) - just announcedDAML-S OWL-SGrounding: greater generality, flexibilityInitial work on expressing conditions, securityMore community support (contributions pages)

Towards 1.0Expressiveness issues; exceptions, lifecycle; process issues


• OWL-final

• Process Model– Exceptions

– Process Control Ontology (lifecycle mgmt.)

– Roles, explicit messaging

– Surface language?

• Grounding– WSDL 1.2

Critical Path to 1.0


Semantic Web Services Initiative (SWSI)

www.swsi.org


SWSI Objectives

• Bring together US and European Semantic Web Services researchers

• Engage in collaborative standardization efforts– Semantic Web Services Language

• DAML-S as a primary input• More attention to working with industry standards efforts

– Semantic Web Services Architecture

• Close collaboration with W3C directions– Web Service Choreography Working Group– Semantic Web Services Interest Group– Likely outcome is a W3C Note


SWSI Structure

• Advisory Committee – Murray Burke, Hans-Georg Stork, Jim Hendler

• Coordinating Committee– Co-chairs: Dieter Fensel and Katia Sycara

• Industrial Advisory Board– Co-chairs: Michael Uschold and ???

• Language Technical Committee – Co-chairs: David Martin and Michael Kifer

• Architecture Technical Committee– Co-chairs: Mark Burstein and Christoph Bussler


End of Part II

ExtraMaterialFollows


Challenges• Profiles: relationship with processes• Process modeling: many issues

– Variability of public/private aspects of Processes– Extending to offline (sub)processes– Generalizing to multiple roles– Failure, transactions

• Where and how to go beyond OWL?– Interface between DL ontology, logical expressions,

algorithm/workflow representation

• Connecting with Industry– Showing compelling value– Not promising too much– Providing an incremental path


(Some) Related Work

Related Industrial Initiatives • UDDI • ebXML

• WSDL • .Net

• XLANG • Biztalk, e-speak, etc

These XML-based initiatives are largely complementary to OWL-S. OWL-S aims to build on top of these efforts enabling increased expressiveness, semantics, and inference enabling automation.

Related Academic Efforts

• Process Algebras (e.g., Pi Calculus)

• Process Specification Language (Hoare Logic, PSL)• Planning Domain Definition Language (PDDL)• Business Process Modeling (e.g., BMPL)• OntoWeb Process Modeling Effort

david martin for daml-s coalition 05/08/2003 part ii: owl-s technical overview profile, process...

Documents

damls coalition

david martin

owls web service discovery

shipping service

service user

web service invocation

toplevel process slide

slides slide