View
217
Download
0
Category
Tags:
Preview:
Citation preview
McIlraith - Knowledge Systems Laboratory DAML PI Meeting 02/14/2001
Mobilizing the Web with
DAML-Enabled Web Services
Sheila McIlraith
Knowledge Systems Laboratory (KSL)Department of Computer Science
Stanford University
(with Son Cao Tran and Honglei Zeng)
McIlraith - Knowledge Systems Laboratory DAML PI Meeting 02/14/2001
Motivation
The Web is evolving from a provider of documents
and images …
McIlraith - Knowledge Systems Laboratory DAML PI Meeting 02/14/2001
Motivation
… to a provider of services
McIlraith - Knowledge Systems Laboratory DAML PI Meeting 02/14/2001
Overview
Problem: today’s web is designed primarily for human use.
We are developing semantic markup of • web services,• web service users’ preferences and constraints• reusable agent procedures
to make services computer-interpretable, use-apparent, and
agent-enabled.
We are developing agent technology that exploits semantic
markup to support automated web service discovery,
execution, composition and interoperation.
McIlraith - Knowledge Systems Laboratory DAML PI Meeting 02/14/2001
Web Service Markup Will Enable
Automation of:
• Web service discoveryFind me an airline service that offers flights to Tuktoyuktuk
• Web service executionBuy me “Harry Potter and the Sorcerer’s Stone” at
www.amazon.com
• Web service selection, composition and interoperationMake my travel arrangements for my IJCAI conference trip
Industry efforts growing
(we are improving with DAML)
Opportunity Area
These are the drivers for web service markup.
McIlraith - Knowledge Systems Laboratory DAML PI Meeting 02/14/2001
Framework
DAML-enabled web pages
Web Service Ontologies
Web Procedures Ontologies
AgentBroker
DAML-enabled personal/company
constraints and prefs...
McIlraith - Knowledge Systems Laboratory DAML PI Meeting 02/14/2001
Key Feature: DAML Markup of Web Services Function, Action, Process-based web service markup:
• declarative • well-founded semantics Ontologies enable:
• reuse • sharing• composition • succinct web site markup
E.g.,service world-altering service purchase purchase-plane-ticket
purchase-UAL-plane-ticket parameters: c-name, origin, dest, d-date, … preconditions: know(c-name), valid(credit-card), … effects: purchased(ticket), debit(credit-card)... rent rent-car ...
Web Service Ontologies
DAML-enabled web pages
McIlraith - Knowledge Systems Laboratory DAML PI Meeting 02/14/2001
Key Feature: Generic Procedures
Agents are tasked in terms of high-level, reusable “generic procedures.”
“The what not necessarily the how.”
Ontologies support sharing,reuse, and composition.
DAML-enabled web pages
Web Service Ontologies
Web Procedures Ontologies
AgentBroker
E-mail ...
E.g.,Travel(cust,origin,dest,date-d,date-r,purpose) Check-purpose-related-restrictions; Book-travel(origin,dest); Book-transportation(dest); Book-hotel(dest)end;
McIlraith - Knowledge Systems Laboratory DAML PI Meeting 02/14/2001
Key Feature: Customizing Generic Procedures
Generic procedures can be further constrained by
DAML-defined constraints• user constraints/preferences, • group constraints, or• instance-specific constraints.
DAML-enabled web pages
Web Service Ontologies
Web Procedures Ontologies
AgentBroker
DAML-enabled personal/company
constraints and prefs...
E.g., • Bob would like to drive if the driving distance is less than3 hours.
• KSL Business air travel should be on an American carrier.
...
McIlraith - Knowledge Systems Laboratory DAML PI Meeting 02/14/2001
Key Feature: Deductive Instantiation
Agent’s KB is automatically constructed relative to the
generic procedure and constraints. KB is updated by web
service responses.
Deductive machinery instantiates the generic procedure
wrt. constraints and world state to
generate web service requests
that the broker executes.
KB
Web Services
Service Ontologies
Procedures Ontologies
AgentBroker
Constraints & Prefs
E-mail ...
McIlraith - Knowledge Systems Laboratory DAML PI Meeting 02/14/2001
Status
DAML = First-order logic and some DAML+OIL
Agent KB representation language = Situation Calculus
Generic procedures representation language = Golog
Deductive machinery = Prolog
Agent Broker = Open Agent Architecture [SRI]
Prototype agent/agent broker constructed.
Preliminary service ontology constructed.
KB
Web Services
Service Ontologies
Procedures Ontologies
AgentBroker
Constraints & Prefs
E-mail ...
McIlraith - Knowledge Systems Laboratory DAML PI Meeting 02/14/2001
Come to Our Demo!
Teaser: Dynamic User Interface with DAML+OIL
McIlraith - Knowledge Systems Laboratory DAML PI Meeting 02/14/2001
Possible Discussion Topics
• What language expressive power do we need? (Let’s help drive language development.)
• What collective tools do we need? (Let’s coordinate and share the effort.)
• How do we interact with each other?
• How do we interact/leverage with industry efforts?
• ...
Recommended