DAML-S: Semantic DAML-S: Semantic Markup for Web Markup for Web ServicesServices

DAML-S Web Services CoalitionDAML-S Web Services Coalition

presented by: Terry R. Paynepresented by: Terry R. PayneCarnergie Mellon UniversityCarnergie Mellon University

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

DAML-S Web Services CoalitionCMU: Anupriya, Ankolekar, Massimo Paolucci,

Terry Payne, Katia Sycara

BBN: Mark Burstein

Nokia: Ora Lassila

Stanford KSL: Sheila McIlraith, Honglei Zeng

SRI: Jerry Hobbs, David Martin, Srini Narayanan

[Yale: Drew McDermott & Manchester: Ian Horrocks]

Slides courtesy of Sheila McIlraith, Stanford KSL

What is DAML-S?DAML-S: A DARPA Agent Markup Language for Services DAML+OIL Ontology for (Web) services

AI-inspired markup language: tailored to the representational needs of Services expressive power well-defined semantics ontologies support reuse, mapping, succinct

markup, ...

Release of DAML-S version 0.5 June,2001 http://www.daml.org/services/

Layered Approach to Language Development

The first major application of DAML+OILLayer exists above DAML+OILFuture versions will build upon emerging layers (e.g. DAML-Rules etc)

DAML-S (Services)

XML (Extensible Markup Language)

RDF (Resource Description Framework)

RDFS (RDF Schema)

DAML+OIL (Ontology)

DAML-S ObjectivesProvide: an upper ontology for describing properties &

capabilities of agents & (Web) services in an unambiguous, computer interpretable markup language.

Desiderata: an ontology of Web services ease of expressiveness enables automation of service use by agents enables reasoning about service properties and

capabilities

Automation Enabled by DAML-S

Web service discoveryFind me a shipping service that transports goods to Dubai.

Web service invocationBuy me 500 lbs. powdered milk from www.acmemoo.com

Web service selection, composition and interoperationArrange food for 500 people for 2 weeks in Dubai.

Web service execution monitoringHas the powdered milk been ordered and paid for yet?

Upper Ontology of Services

PresentingService Profiles

Service Profile Presented by a service. Represents

“what the service provides”

One can derive: Service Advertisements Service Requests

DAML-S:

DAML-S Service Profile (Overview)

High-level description of a service and its provider description of service (human readable) specification of functionalities service provides functional attributes (requirements and

capabilities)

Profile used for populating service registries automated service discovery matchmaking

DAML-S Service Profile (Overview)

ProvenancProvenance e DescriptioDescriptionn

Functional Functional AttributesAttributes

Functionality Functionality DescriptionDescription

DAML-S Service ProfileProvenance Description

Information and Provenance about the Service serviceName & textDescription intendedPurpose & role of 3rd Party Actors

Details about 3rd Party Actors Requesters Providers

DAML-S Service ProfileFunctionality Description

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

of:

preconditions accessConditions inputs

outputs conditionalOutputs effects

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

DAML-S Service ProfileFunctional 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:

Upper Ontology of Services

DescribingService Models

Service Process Describes how a

service works.

Facilitates (automated)

Web service invocation

composition interoperation monitoring

DAML-S:

DAML-S Service Model (Overview)

Service Model may be used to1) to perform a more in-depth analysis of whether the

service meets its needs;2) to compose service descriptions from multiple

services to perform a specific task;3) during the course of the service enactment, to

coordinate the activities of the different participants;4) to monitor the execution of the service.

For non-trivial services, the first two tasks require a model of action and process, the last two involve, in addition, an execution model.

DAML-S Service Model (Overview)

DAML-S Service Model“How does it work?”

Each service is conceived as simple or composite process (event/action)

Associated with each service is a set of inputs, outputs, preconditions and effects (function and action metaphor)

Composite processes are compositions of simple or other composite processes in terms of constructs such as sequence, if-then-else, fork,...

Data flow and Control flow should be described for each composite service

A black box and glass box view are given of each composite service

Function/Dataflow Metaphor

Acme Book

Truck

Shipment

Acme Book

Truck

Shipment

Input:

• confirmation #• ...

Output:

• failure notification• …

truck available+

valid credit card

Y

N

?

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

AI-inspired Action/Process Metaphor

Input:

• confirmation #• ...

Output:

• failure notification• …

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

Acme Book

Truck

Shipment

AcmeTruckShippingAcmeTruckShipping

www.acmeair.com

book flight service

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

• confirmation no.• ...

• failure notification• errror information• …

?

www.acmehotel.com

book hotel service

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

• confirmation no.• ...

• failure notification• …

?

www.acmecar.com

book car service

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

• confirmation no.• ...

• failure notification• …

?

Composite Process

• • • • • • • •

• • • • • • • •

?• • • • • • • • •

• • • • • • • • •

Input &PreconditionsInput &Preconditions

Output &Effects

Output &Effects

• • • •

• • • •

• • • •

• • • •

• • • •

• • • •

• • • •

• • • •

Composite Process (cont)

Acme

Truck

Shipping

Service

Acme

Truck

Shipping

Service

expands

AcmeTruckShipping ExpandedAcmeTruckShipping

truck available+

valid credit card

Y

N

Confirm Shipping Region

Get Quote

Get Shipping Dates

Book Truck Shipment

AcmeTruckShipping ExpAcmeTruckShipping

expand

Composite Process (cont)

Upper Ontology of Services

Supporting aService Grounding

Service Process Provides a specification of

service access information.

Specifies: communication protocols,

transport mechanisms, etc.

E.g., SOAP, HTTP forms, KQML, OAA ACL, Java RMI, RPC, etc.

DAML-S:

Under Construction …

Upper Ontology of ServicesReview:

Related WorkRelated Industrial Initiatives

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

DAML-S intends to build on top of these efforts exploiting increased expressiveness, semantics, inference that enables automation.

Related Academics Efforts Process Algebras (e.g., Pi Calculus) Process Specification Language (Hoare Logic, PSL) Planning Domain Definition Language (PDDL) Business Process Modeling (e.g., BMPL) Service Description Languages (e.g., LARKS)

UDDI ebXML

WSDL (dot) .NET

XLANG BizTalk, e-speak etc