david martin for daml-s coalition 12/18/2002 daml-s: bringing services to the semantic web david...

David Martin for DAML-S Coalition 12/18/2002

DAML-S:Bringing Services tothe Semantic Web

David Martin

SRI International

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


DAML-S Web Services Coalition

BBN: Mark Burstein

CMU: Massimo Paolucci, Katia Sycara

ICSI: Srini Narayanan

Nokia: Ora Lassila

Stanford KSL: Sheila McIlraith*

SRI: David Martin*

Southampton: Terry Payne*

USC-ISI: Jerry Hobbs

Yale: Drew McDermott*Contributed to these slides


Outline

Motivation & Goals DAML-S technical overview

Profile, Process & Grounding ontologies

Achievements to dateReleases, tools & applications

ChallengesNext Steps


Convergence on Services• Commercial vendors, media, forecasters, etc.

– Intranets, not just internets

• W3C Web services efforts• Semantic Web community

– DAML-S; WSMF & other EU efforts– ISWC: 10 services-related papers, 7 posters

• Grid computing (OGSA)• Ubiquitous computing (devices)

– Mobile access to services

A remarkable opportunity– Bringing behavioral intelligence to the Web


What is DAML?• A DARPA program

• An input to the W3C Semantic Web activity• Draft for the Web Ontology working group

• A markup language

www.daml.org


Characteristics of DAML• Based on XML & RDF(S)

– Beyond RDF: properties of properties, equivalence and disjointness of classes, more constraints, etc. Feature comparison: https://www.daml.org/language/features.html

– Layered approach XML => RDF(S) => DAML+OIL => (DAML-L) => DAML-S

• Semantics for Web resources from Knowledge Representation concepts– DAML+OIL: can be regarded as a description logic

– Ontologies

– Logical rules & inference

• DAML-S: Extension to Services

https://www.daml.org/language/features.html


What is DAML-S?

• DARPA Agent Markup Language for Services • A DAML+OIL 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



Layered Approach to Language Development

DAML-??? (Rules, FOL?)

XML (Extensible Markup Language)

RDF (Resource Description Framework)

RDFS (RDF Schema)

DAML+OIL OWL (Ontology)

DAML-S (Services)

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


DAML-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 DAML-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?


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: Capability Description

• Specification of what the service provides– High-level functional representation in terms of:

• preconditions

• inputs

• (conditional) outputs

• (conditional) effects

Summarizes the top-level Process (described by Service Model)


Service Profile: Functional Attributes

– geographical scopePizza Delivery only within the Pittsburgh area

– quality descriptions and guarantees

Stock quotes delivered within 10 secs

– service types, service categories

Commercial / Problem Solving etc

– service parametersAverage Response time is currently ...

Provide supporting information about the service, including:


• Class-hierarchical yellow pages– Implicit capability characterization

– Arrangement of attributes on class hierarchy

– Can use multiple inheritance

• Process summaries for planning purposes– More explicit

– Inputs, outputs, preconditions, effects

– Less reliance on formal hierarchical organization

– Summarizes process model specs

Service Profile: Styles of use


Exploiting Taxonomies of ServicesServiceProfile

ProductProvidingService

Manufacturing

Transportation

ActionService

InfoService

PhysicalProductService Repair

InformationProduct+

physicalProduct+manufacturer+

deliveryRegion*deliveryProvider*

deliveryType

Physical_Product+

transportationMode+geographicRegion+

physicalProduct+

Tie in with UDDI, UNSPSC, …DL Basis for matchmakingMultiple profiles; multiple taxonomies

nameprovider

role+avgResponseTime?

…

FeeBased feeBasis+paymentMethod+


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

• • • •

• • • •


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


• Conditional outputs & effects

• Parameter bindings<rdf:Description rdf:about="#FullCongoBuy">

<sameValues rdf:parseType="daml:collection"> <ValueOf atClass="#FullCongoBuy“ theProperty="#fullCongoBuyBookISBN"/> <ValueOf atClass="#LocatedBookOutput“ theProperty="outInCatalogBookISBN"/> <ValueOf atClass="#CongoBuyBook“ theProperty="#congoBuyBookISBN"/></sameValues>

Pushing the limits of DAML+OIL expressiveness

Process Model: Recent evolution


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

• Examples: HTTP forms, SOAP, KQML, CORBA IDL, OAA ICL, Java RMI


DAML-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 DAML-S


DL-based Types

WSDL

DAML-S

Process Model

Atomic Process

Operation Message

Inputs / Outputs

Binding to SOAP, HTTP, etc.


DAML-S / WSDL Grounding (cont’d)


daml-property

daml-s-process

inputX

daml-propertyoutputY

AtomicProcess

WSDLDocument

<message …> <part …>

<message …> <part …>

<operation …>

<binding …>

DAML-S / WSDL Grounding (cont’d)


Review: Upper Ontology of Services


Pro

cess

Mod

el

Gro

undi

ng

Development … Deployment … Use …

Publication

Simulation

Verification

Discovery

Composition

Key:

Selection

Invocation, Interoperation

Monitoring, Recovery

Pro

file


Path of EvolutionRelease 0.5 (May 2001)

Initial Profile & Process ontologies

Release 0.6 (December 2001)Refinements to Profile & ProcessResources ontology

Two approaches to formal semanticsSycara/Ankolekar, McIlraith/Narayanan

Release 0.7 (October 2002)DAML-S/WSDL GroundingProfile, Process Model refinementsMore complete examples

Towards 1.0Expressiveness issues; process modeling; industry tie-in


Related ActivitiesWeb site & mailing lists

http://www.daml.org/services/[email protected]

UsersUMCP (Hendler/Parsia), UMBC (Finin), Manchester (Goble), CMU (Sadeh), Lockheed-

Martin, Ultralog, beta-reviewers, …

ToolsDAML-S publications

WWW10 SW Workshop (2), SWWS, WWW11, Coordination 2002, AAMAS, ICSW (4), IEEE Computer, IEEE Intel. Systems…

W3C Web services activitiesDesignated liaison for WS Arch. WG; Katia Sycara

ExperimentUse cases


Tools and ApplicationsDAML-S is just another DAML+OIL ontology

All the tools & technologies for DAML+OIL are relevant

Some DAML-S Specific Tools and Technologies: Discovery, Matchmaking, Agent Brokering: CMU, SRI (OAA), Stanford KSL

Automated Web Service Composition: Stanford KSL, BBN/Yale/Kestrel, CMU, MIT, Nokia, SRI

DAML-S Editor: Stanford KSL, SRI, CMU (profiles), Manchester

Process Modeling Tools & Reasoning: SRI, Stanford KSL

Service Enactment /Simulation: SRI, Stanford KSL

Formal Specification of DAML-S Operational/Execution Semantics:

CMU, Stanford KSL, SRI


Challenges• Finding the “80/20” line• 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 DAML+OIL?– Interface between DL ontology, logical expressions, algorithm/workflow

representation

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


Next steps / prioritiesFocus on use cases architectureJoint committee forming …Move to OWLModel information servicesProfile: More substantial illustrative taxonomies

Tie in with existing taxonomies where possible (e.g. UNSPSC)

Process ModelEvaluate potential tie-in with an existing effort (WSFL?)

Support real-world useDescribing and using public WSDL servicesPossible collaborations with other SemWeb projectsDemos directed towards Web services community

Tools DAML-S API


(Some) Related Work

Related Industrial Initiatives • UDDI • ebXML

• WSDL • .Net

• XLANG • Biztalk, e-speak, etc

These XML-based initiatives are largely complementary to DAML-S. DAML-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


SummaryThe service paradigm will be a crucial part of the Semantic WebDAML-S supports service descriptions that are integral with

other Semantic Web meta-dataDAML-S aims to enable automatic discovery, selection,

invocation, composition, monitoring of servicesInitial versions of Profile, Process, and Grounding ontologies

are availableMany challenges remainWe’re interested in synergy with related work



Acknowledgements

• Slides created by David Martin, Sheila McIlraith, Terry Payne

• Ontology images created by Terry Payne, CMU

david martin for daml-s coalition 12/18/2002 daml-s: bringing services to the semantic web david...

Documents

damls coalition

damls semantics

damls web service discovery

characteristics of daml

services slide

web slide

service model slide

language development