Semantics Web Services Language: Scope and Objectives

1
Semantics Web Services LanguageScope and
Objectives

• Sheila McIlraith
• Knowledge Systems Lab, Stanford University
• April 11, 2003

2
Context

• Context dictates what we can do and how we should
  do it
• Fast-paced industry initiative on Web services
• Minimal interest in semantic web issues

3
How?

• Must integrate with and complement industry
  efforts
• Convince mainstream of the merits/value-added of
  SWS
• demonstrate value-added through demos of cool
  apps
• facilitate adoption of SWS through development of
  tools
• integrate with existing standards
• Lead and influence standards efforts rather than
  try to re-engineer them.

4
What?

• Let the applications, unique to Semantic Web
  Service drive language development

5
Applications Automation Tasks

• Automation of
• Web service discovery
• Find me a shipping service that will transport
  frozen
• vegetables from San Francisco to Tuktoyuktuk.
• Web service invocation
• Buy me Harry Potter and the Philosophers
  Stone at
• www.amazon.com
• Web service selection, composition and
  interoperation
• Make the travel arrangements for my WWW11
  conference.
• Web service execution monitoring
• Has my book been shipped yet?
• Web service mediation
• Web service simulation and verification

6
Observations

• DAML-S is appropriate for WS discovery and
  invocation
• DAML-S Rules (or the like) may be sufficient
  for WS interoperation, semantic translation
• Need something more expressive (and different)
  for composition, complex mediation, simulation
  and verification. Partially addressed by
  industry initiatives such as XLANG, WSFL and
  BPEL4WS.

7
Language Desiderata (incomplete)

• Declarative
• Compositional
• Well-defined semantics
• Understandable usable (tools)
• Amenable to automated reasoning techniques
• Not just interface descriptions, but functional
  and behavioral specifications of component
  software
• Integrated with existing industry standards XML,
  SOAP, WSDL, BPEL(?)
• Addresses both the KR and PL aspects of WS.