Mobilizing the Web with DAML-Enabled Web Services
Knowledge Systems Lab, Department of Computer Science, Stanford University
Sheila McIlraith, Son Cao Tran, Honglei Zeng, Richard Fikes
Jessica Jenkins, Ron Fadel, Deborah McGuinness
http://www.ksl.stanford.edu/projects/daml
Objective:
The web is evolving from a provider of documents and images to a provider of services. Today’s web was designed primarily for human use.
We exploit DAML markup to enable automated web service discovery, execution, composition and interoperation through:
• Semantic markup of web services that enables them to be computer-interpretable, use-apparent and agent-ready.
• Agent technology that exploits this semantic markup to support automated web service discovery, execution, composition and interoperation.
The Vision
DAML Markup of Web Services
Ontologies of Generic Procedures
Ontologies of sharable, reusable generic procedures.
“The what but not necessarily the how”
Web Procedures
Ontologies
Web Service
Ontologies
DAML-Defined Constraints & Preferences
Customize generic procedures
• personal constraints
• group/company constraints
• instance-specific constraints
Agent
Broker
DAML-enabled
web pages
DAML-enabled
personal/company
constraints and prefs
E-mail
Tasking Agents -Generic Procedures and Deductive Machinery
• Humans or other agents task agent. Task expressed
as generic procedure call, potentially in conjunction with
further constraints.
• Generic procedures are deductively instantiated
with respect to the agent KB, generating web service
requests that are sent to the agent broker.
• Generic procedures result in different sequences of
web services depending upon the constraints, state
of the world, and web services.
• Action-based metaphor:
information gathering & world altering web services.
• Markup is declarative and semantically grounded.
• Ontologies of web services facilitate creation, sharing,
reuse, composition; support succinct web site markup.
• Markup is independent of agent implementation.
• Markup enables declarative specification of API.
...
KB
Agent’s KB
• Automatically constructed from
ontologies and web site markup
in response to agent’s task.
• Updated by web service
responses.
Agent Broker
• Sends requests to and dispatches
responses from web services.
• Web service ontologies facilitate location
of appropriate web services.
Status: July, 2001
 DAML = transitioning to DAML-S from DAML+OIL +FOL
Agent’s KB representation language = Situation Calculus
 Generic procedures representation language = Golog
 Deductive machinery = Prolog
 Agent Broker = Open Agent Architecture (OAA) [SRI]
 Prototype agent/agent broker constructed.
 Rudimentary service ontology constructed.