DAMLS: Semantic Markup for Web Services

1
DAML-S Semantic Markup for Web Services

• DAML-S Web Services Coalition
• presented by Terry R. Payne
• Carnergie Mellon University

http//www.daml.org/services/
2
DAML-S Web Services Coalition

• CMU 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
3
What is DAML-S?

• DAML-S A DARPA Agent Markup Language for
  Services
• DAMLOIL 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/

4
Layered Approach to Language Development

• The first major application of DAMLOIL
• Layer exists above DAMLOIL
• Future versions will build upon emerging layers
  (e.g. DAML-Rules etc)

DAML-S (Services)
5
DAML-S Objectives

• Provide
• 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

6
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 and
  interoperation
• Arrange food for 500 people for 2 weeks in Dubai.
• Web service execution monitoring
• Has the powdered milk been ordered and paid for
  yet?

7
Upper Ontology of Services
8
PresentingService Profiles
DAML-S

• Service Profile
• Presented by a service.
• Represents
• what the service provides
• One can derive
• Service Advertisements
• Service Requests

9
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

10
DAML-S Service Profile (Overview)
Functionality Description
Provenance Description
Functional Attributes
11
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

12
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)

13
DAML-S Service ProfileFunctional Attributes

• Provide supporting information about the service,
  including

• geographical scope
• Pizza 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 parameters
• Average Response time is currently ...

14
Upper Ontology of Services
15
DescribingService Models
DAML-S

• Service Process
• Describes how a service works.
• Facilitates
• (automated) Web service invocation
• composition
• interoperation
• monitoring

16
DAML-S Service Model (Overview)

• Service Model may be used to
• to perform a more in-depth analysis of whether
  the service meets its needs
• to compose service descriptions from multiple
  services to perform a specific task
• during the course of the service enactment, to
  coordinate the activities of the different
  participants
• 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.

17
DAML-S Service Model (Overview)
18
DAML-S Service ModelHow 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

19
Function/Dataflow Metaphor
Input
Output

• confirmation
• ...

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

Acme Book Truck Shipment
Y
truck available valid credit card
?
N

• failure notification

20
AI-inspired Action/Process Metaphor
Output

• confirmation
• ...

Input

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

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

Effect
Acme Book Truck Shipment
Y
truck available valid credit card
?
Preconditions
N

• knowledge of
• the input
• ...

• failure notification

Output
Effect

21
Composite Process
Output Effects
AcmeTruckShipping

• confirmation no.
• ...

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

www.acmecar.com book car service
?
Input Preconditions

• failure notification

?

• confirmation no.
• ...

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

• confirmation no.
• ...

www.acmehotel.com book hotel service
?

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

www.acmeair.com book flight service
?

• failure notification

• failure notification
• errror information

22
Composite Process (cont)
AcmeTruckShipping
ExpandedAcmeTruckShipping
Acme Truck Shipping Service
expands
23
Composite Process (cont)
expand
AcmeTruckShipping
ExpAcmeTruckShipping
24
Upper Ontology of Services
25
Supporting aService Grounding
DAML-S

• 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.

Under Construction
26
Upper Ontology of Services
Review
27
Related Work

• Related 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)

28
Exploiting Ontologies of Services
DAML-S
Service
Shipping
Purchase
BuyBook
BuyTicket
AirShipping
BoatShipping
TruckShipping
BuyAirTicket
AcmeTruckShipping
BuyConcertTicket
29
Tools and Applications
DAML-S provides a means of describing Web
services. Its just another DAMLOIL ontology ?
all the tools and technologies that exist for
DAMLOIL are relevant Some DAML-S Specific Tools
and Technologies Extending DAML-S DAML-S
Coalition (security, symbol grounding, )
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
30
Challenges

• Technical Issues
• DAMLOIL not sufficient for the process model
• Laundry list of unaddressed resolved issues
• (SRI CMU will mention some this afternoon)
• (some will be mentioned in Breakout tomorrow)
• Connecting with Industry Initiatives with User
  Community
• need to connect DAML-S with industry initiatives
• need people in industry ( in DAML) to mark up
  services with DAML-S
• concern industrys lack of adoption of RDF
• Tools availability
• DAMLOIL reasoner
• DAML-S editor

31
Challenges

• Technical Issues
• DAMLOIL not sufficient for the process model
• Laundry list of unaddressed resolved issues
• messages, synchronization, conversation
  protocols, exceptions and transaction,
• multiple participants, scripts,
  unification/binding, constraints, ontologies of
  processes,
• service grounding, ...
• Connecting with Industry Initiatives with User
  Community
• need to connect DAML-S with industry initiatives
• need people in industry ( in DAML) to mark up
  services with DAML-S
• concern industrys lack of adoption of RDF
• Tools availability
• DAMLOIL reasoner
• DAML-S editor

32
Challenges

• Technical Issues
• DAMLOIL not sufficient for the process model
• Laundry list of unaddressed resolved issues
• (SRI CMU will mention some this afternoon)
• (some will be mentioned in Breakout tomorrow)
• Connecting with Industry Initiatives with User
  Community
• need to connect DAML-S with industry initiatives
• need people in industry ( in DAML) to mark up
  services with DAML-S
• concern industrys lack of adoption of RDF
• Tools availability
• DAMLOIL reasoner
• DAML-S editor

33
We Want Your Input!

• Status DAML-S version 0.5 released June, 2001.
• Please get involved!
• ? Break-out Session (Friday)
• ? Try DAML-S for your application give
  feedback
• ? DAML-S version 0.5 and related papers
• http//www.daml.org/services/
• ? mailing list
• www-ws_at_w3.org (technical discussions)
• daml-services_at_daml.org (announcements)

34
Acknowledgements

• Slides created by Sheila McIlraith, KSL Stanford
• Ontology images created by Terry Payne, CMU

35
Who Will Use DAML-S?

• Web service providers (e.g., Amazon, Intelink,
  United Airlines)
• ? mark up their services
• 3rd party Web page designers (e.g., Web
  Designers)
• ? mark up clients services
• 2nd-ary Web service providers (e.g.,
  Travelocity, My Simon)
• ? exploit others services to create add-on
  services
• ? use/write agent software to find/execute/compose
  other services
• Web service end users (e.g., Joe, Analysts)
• ? characterize their needs
• ? use/write agent software to find/execute/compose
  services