Autonomous Semantic Web
Services
Katia Sycara
Intelligent Software Agents and Web
Technologies Lab
Carnegie Mellon University
katia@cs.cmu.edu
http://www.cs.cmu.edu/~softagents/
ISRI-Seminar-05
Talk Overview
The Vision
Requirements and Challenges
Web Services
Semantic Web
Multi Agent Systems (MAS)
Semantic Web Services
OWL-S
Future Directions
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From the Internet to the Semantic Web
Old World :
New World:
“The eye-ball Web”
“The Semantic Web”
The architecture of the Web is
geared towards delivering
information visually (Internet
filled with human readable
information)
Source: IBM
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The content of the Web
becomes computer intelligible
(Internet filled with machine
understandable information)
ISRI-Seminar-05
From the Internet to Web Services
Old World :
New World:
“The eye-ball Web”
“The transactional Web”
The architecture of the Web is
geared towards delivering
information visually (Internet
filled with human readable
information)
Source: IBM
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The architecture of the Web
geared towards exchanging
information between
applications (Internet filled
with executables)
ISRI-Seminar-05
From the Internet to Semantic Web Services
Old World :
New World:
“The eye-ball Web”
“The Coordination Web”
The architecture of the Web is
geared towards delivering
information visually (Internet
filled with human readable
information)
Source: IBM
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The architecture of the Web
geared towards applications
that intelligibly coordinate
information exchanges
(Internet filled with machine
understandable executables)
ISRI-Seminar-05
From the Internet to Autonomous Semantic Web Services
Old World :
New World:
“The eye-ball Web”
“The Agent Web”
The architecture of the Web is
geared towards delivering
information visually (Internet
filled with human readable
information)
Source: IBM
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The architecture of the Web
geared towards goal directed
applications that intelligibly
and adaptively coordinate
information and action
(Internet filled with contextaware and self organizing
agents)
ISRI-Seminar-05
The Integration Challenge
Integrate multiple independent and heterogeneous
Data repositories
Processes
Applications
Ensure
Semantic equivalence of equivalent concepts
Performance
Communication of “semantic” agreements
Dynamism: real time access works accurately
Flexibility: systems enter and leave integration
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The Integration Past and Future?
Numerous solutions to date (since the ’70s):
Tool driven
Data driven
Process driven
Model driven
Web services
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Web Services - A New Paradigm?
Web Services heralded as:
“… self-contained, self-describing, modular applications that can be published,
located, and invoked across the Web…”
Which will allow…
…on the fly composition of new functionality through the use of loosely
coupled reusable software components
…decomposition and distribution of large-scale processing tasks into
component tasks executed simultaneously across many devices
“Web services are expected to revolutionize our life in much the same way as the
Internet has during the past decade or so.” (Gartner)
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So what is new about Web Services?
Component-Based Model
Web Services Model
Tightly coupled software applications
(high dependencies between
systems)
Loosely coupled software applications
(low dependencies between
applications)
Mainly designed for processes within
the enterprise
Mainly designed for processes across
enterprises
Uses different protocols and
technologies (e.g., Microsoft DCOM,
CORBA)
Uses standard protocols and
technologies (e.g., XML, SOAP, WSDL,
HTTP)
Web Services do for programs what the Web did for Documents
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Requirements and Challenges
Information and action integration across the Web (currently the
user is the “glue”)
System integration/interoperability Web-wide (within and across
organizations)
Semantic Interoperability
Consistency of behavior of long running transactions (both for ecommerce and e-science) in the face of partial, distributed failures
Dynamic and goal-directed discovery, interaction and composition
of applications across the Web
Tension between the “anarchy” of the Web and the requirements for
reliable, consistent, trusted transactions of e-commerce and e-science
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Current State: Web Services Standards
SOAP: XML based web services communication protocol
Limitations
Unbounded message format
Has no communicative speech acts (cannot determine intention of
actors or type of the message)
WSDL: Structured mechanism to describe a WS
interface
Abstract operations that a Web Service can perform
Format of messages it can process
Protocols it can support
Physical bindings to URIs and protocols
Limitations
No semantics for message sequencing and correlation
No semantics for message content
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Current State: Web Services Standards (cnt.)
BPEL: Description of how Web Services are composed
Flow Model describes the structure of the business
process in terms of activities of process steps and data
and control links
Global Model
• Describes interaction between provider and requester
• Mappings between internal operations and WSDL port types
Limitations
No IOPEs
Allows execution of a manually constructed composition
UDDI: Directory Service for Web Services
Limitations: keyword searches, limited capability search
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Tackling Semantic Interoperability…
Lack of Semantic Interoperability is a major hurdle for
Discovery
• Different terms used for advertisements and requests
Invocation
• Different specs for messages and WS interface
Understanding
• Interpreting the results returned by the Web service
Composing Services
• Reconciling private goals with goals of the WS
Negotiating contracts & communications
• Different terminology and protocols used
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Is this a real problem?
World Wide Annual Integration plus Data Quality Costs:
$1 Trillion / year
“The problem is not in the plumbing. It’s in the semantics”
(quotation from Michael Brodie’s invited talk at ISWC 2003)
Note: some standards committees, e.g. WSDL and UDDI start realizing this
truth and planning to incorporate RDF and OWL in these standards
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Three Significant Technological Visions
Semantic Web
Multi Agent Systems (MAS)
Semantic Web Services
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Autonomous Semantic Web Services Stack Diagram
Autonomous Semantic Web Services
Eg Contracts; Info Integration; Business Process Automation; Tasking
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RDF Model & Syntax
Semantic Web Stack
XML
URI
RDF Schema
SOAP
DAML+OIL
WSDL
Rules eg RuleML
Messaging
Proof
Directories, e.g. UDDI
Logic Framework
Process Specifications
Trust
Web Services Stack
Choreography eg BPEL
Namespaces
Unicode
Copyright Semantic Web Services Initiative
Encryption, Signature
ISRI-Seminar-05
Semantic Web
Definition
Goal of Web Semantics: Development of common representation format, shared
ontologies, reasoning mechanisms, and query engines to support improved
utilization of Web knowledge
Semantic Web technologies and tools
Rdf
OWL
“The Semantic Web is an extension of the current Web in which information is given a
well-defined meaning, better enabling computers and people to work in
cooperation. It is the idea of having data on the Web defined and linked in a way
that it can be used for more effective discovery, automation, integration and reuse
across various applications. The Web can reach its full potential if it becomes a
place where data can be processed by automated tools as well as people”
From the W3C Semantic Web Activity statement
Semantic Web: semantic metadata and ontologies for web
content to enable information access, integration,
interoperation and consistency.
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Semantic Web
OWL
OWL is a W3C standard
OWL is a Description Logic-based Language: provides the basic
constructs to describe ontologies
Definition of concepts
Relations between concepts
Special relation: subclass for generalization
Effectively computable
• Good optimization algorithms support inference
OWL specifications
W3C page on OWL
• http://www.w3c.org/2001/sw/WebOnt/
OWL Guide and language reference
• http://www.w3.org/TR/owl-guide/
• http://www.w3.org/TR/owl-ref/
Tutorials
Costello and Jacobs’ OWL tutorial: http://www.xfront.com/owl
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RCal Calendar Agent
Retsina Semantic Web Calendar Agent supports:
Browsing of agendas and schedules marked up in OWL & RDF
Invocation of related tasks, such as scheduling meetings and email
Integration of selected meetings and events into MS Outlook
Can parse markup using several ontologies, including
Hybrid ICal Calendar Ontology
Dublin Core Ontology
Friend-of-a-Friend Ontology
Schedule markup using other ontologies can be
accessed via translation agents
DMA2ICal Agent converts OWL Meeting Agenda markup into ICal
Markup.
http://www.daml.ri.cmu.edu/Cal
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Importing Schedules into MS Outlook
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Multi Agent Systems
Agent Characteristics
A software agent is a computational entity with the following key
characteristics:
Situatedness: agent receives sensory inputs from its environment
and outputs actions (physical environments, Internet)
Autonomy: agent is goal-directed and has control over its internal
state (can reason and act without direct intervention of others)
Interactivity/Sociability: agents interact in peer to peer fashion with
humans and/or other agents in pursuit of their goals (individual or
collective)
Adaptivity: agents respond reactively or proactively to changes in
their environment
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Relation Agents/Web Services
Decision Making
Goal Directed
Situation Awareness
Coordination/Teaming
Network Interface Mgm
Binding of end points
Data Serialization
Remote Procedure Call
Agent
Data structures to concepts
Semantic
Web Service Interaction Management
Service Composition
Web Service
Network
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Multi Agent Systems
Autonomous behavior is needed for Open
Environments & Complex Interactions
Open Environments
No predefined structure
Agents leave and join the society dynamically
Communication is not ensured all the time
Information sources may appear and disappear
Complex Interactions
Dynamic task decomposition & allocation
Provider selection
Planning for composition of MAS reasoning
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Multi Agent Systems
Generic Tasks in Open Environments
Agents must be able to:
discover each other. We distinguish the notion
of agent identity from the notion of agent
functionality.
Identity is found through Agent Name
Services (ANS)
Functionality/capability is found through
Middle Agents
interact/transact with each other
compose results of their reasoning
monitor progress of delegated tasks
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Multi Agent Systems
RETSINA Multi-Agent Organization
Distributed
adaptive
collections of
agents
(autonomous
services) that
coordinate to do
tasks on the user’s
behalf
User 1
User 2
Goal and Task
Specifications
Results
Interface Agent 1
Interface Agent 2
RETSINA download at
www.cs.cmu.edu/~softagents
Solutions
Agent/Service
Info & Service
Requests
Agent/Service2
Agent/Service t
Information and Task Execution
Conflict Resolution
Replies
MiddleAgent 2
Agent/Service1
Queries
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Interface Agent i
Tasks
Advertisements
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User u
Info
Source 1
Agent/Service n
Answers
Info
Source 2
Info
Source m
ISRI-Seminar-05
Multi Agent Systems
Agent Discovery and Mediation
Agents that provide services advertise their expertise/capabilities
to middle agents
Requester agents ask middle agents for agents with particular
capabilities
Middle agents match requests to advertisements and return results
Communication protocols include formal semantics and ontologies
for interoperation
The discovery scheme enables system robustness through
functional substitutability of agents
Our research at CMU has identified 28 types of middle agents with
different functionalities, protocols and performance tradeoffs
Hao-Chi Wong and Katia Sycara “A taxonomy of middle agents for the Internet”, In Proceedings of
the Fourth International Conference on Multi-Agent Systems (ICMAS'2000)
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Multi Agent Systems
Matchmaker
Request for service
Requester
Contact information of
providers that match the
request
Matchmaker
Advertisement
of capabilities
Delegation of service
Results of
service request
Provider 1
This is blueprint for the “SOA Triangle”
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Provider n
ISRI-Seminar-05
Multi Agent Systems
Facilitator
Delegation of service
+ preferences
Requester
Facilitator
Results of service
Delegation
of service
Results
of service
Provider 1
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Advertisement
of capabilities
Provider n
ISRI-Seminar-05
Multi Agent Systems/Semantic Web Services
Problem of Discovery
Requester and provider have different views
Provider sells Mutual Funds
Requester wants Mutual Funds of European Companies
There is no exact match
Matchmaker or Facilitator need to exploit the semantics of
advertisements and requests to recognize partial matches
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Semantic Web Services
OWL-S Ontology
OWL-S is an OWL ontology to describe Web services
OWL-S has been accepted as a Note by W3C (12/1/2004)
OWL-S leverages on OWL to
Support
Support
Support
Support
capability based discovery of Web services
automatic composition of Web services
automatic invocation of Web services
monitoring of the execution of Web services
Complete do not compete
OWL-S does not aim to replace the Web services standards
rather OWL-S attempts to provide a semantic layer
• OWL-S relies on WSDL for Web service invocation (see Grounding)
• OWL-s Expands UDDI for Web service discovery (OWL-S/UDDI mapping)
http://www.daml.org/services/owl-s/
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Semantic Web Services
Acknowledgements to the
OWL-S Web Services Coalition
BBN: Mark Burstein
CMU: Katia Sycara, Massimo Paolucci, Naveen Srinivasan
De Montfort University: Monika Solanki
ISI: Jerry Hobbs
U. Of Maryland: Bijan Parsia
Nokia: Ora Lassila
Southampton: Terry Payne
Stanford KSL: Deborah McGuiness
SRI: David Martin
U. Of Toronto: Sheila McIlraith
Vrije Universiteit: Marta Sabou
Yale: Drew McDermott
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Semantic Web Services
Relation to Web Services Technology
Discovery
What it does
Choreography
How is done
Invocation
How to invoke
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OWL-S
Web Services
Infrastructure
Profile
UDDI API
Process Model
BPEL4WS
Grounding+
WSDL/SOAP
WSDL/SOAP
ISRI-Seminar-05
Semantic Web Services
OWL-S Upper Ontology
•WS Capability specification to assist
Discovery
•Used for advertisement of service
Capabilities
•Used for requesting WS with desired
capabilities
• Mapping to WSDL
• communication protocol (RPC, HTTP, …)
• marshalling/serialization
• transformation to and from XSD to OWL
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• Control flow of the service
•Black/Grey/Glass Box view
• Protocol Specification
• Abstract Messages
ISRI-Seminar-05
Semantic Web Services
Capability Description
Preconditions
Set of conditions that should hold prior to service invocation
Inputs
Set of necessary inputs that the requester should provide to invoke
the service
Outputs
Results that the requester should expect after interaction with the
service provider is completed
Effects
Set of statements that should hold true if the service is invoked
successfully.
Service type
What kind of service is provided (eg selling vs distribution)
Product
Product associated with the service (eg travel vs books vs auto parts)
Service Parameters (e.g. security, QoS etc)
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Semantic Web Services
CMU’s Matching Algorithm
Massimo Paolucci, Takahiro Kawamura, Terry R. Payne,
Katia Sycara; "Semantic Matching of Web
Services Capabilities." In Proceedings of the 1st
International Semantic Web Conference (ISWC2002),
2002
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subsume
Thing
Vehicle
exact
Car
Coupe
plug-in
Matching of I/O of the request with I/O of the
advertisement
Four degrees of match
Exact
Subsume
Plug-In
Fail
Efficient implementation given correct indexing
of advertisements
Linear complexity with some restrictions on
the query
Current work aims at generalizing matching
process to include preconditions/effects service
and product types and service parameters
Price
Truck
Sedan
Luxury
Mid-Size
ISRI-Seminar-05
Semantic Web Services
Integration of OWL-S Matchmaker and UDDI
Publish Port
Inquiry Port
Capability Port
UDDI
Business Registry
Green Pages
Yellow Pages
White Pages
• OWL-S Profile has been mapped
to UDDI data structure
• OWL-S Web services can be
advertised in UDDI as any
other Web service
(see Paolucci et al 2002)
OWL-S
Matching
Engine
CMU UDDI is publicly available at
www.daml.ri.cmu.edu/matchmaker
or on SemWebCentral
• CMU OWL-S Matching engine has been
integrated within UDDI server
• CMU UDDI server provides
• Normal UDDI Publish/Inquiry ports
• Complete interoperability with any
UDDI Client
• Capability Port provides OWL-S based
capability requests
(see Srinivasan et al 2004)
http://projects.semwebcentral.org/projects/mm-client/
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A variant of the CMU UDDI is in use at the NTT UDDI Business
Registry (The main public UDDI in Japan) (see Kawamura et al
2003, 2004)
Copyright Katia Sycara
ISRI-Seminar-05
Semantic Web Services
Process Model
Process Model
Describes how a service
works: internal processes of
the service
Specifies service interaction
protocol
Specifies abstract messages:
ontological type of
information transmitted
Facilitates
Web service invocation
Composition of Web services
Monitoring of interaction
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Semantic Web Services
Definition of Process
A Process represents a transformation (function). It is characterized by four
parameters
Inputs: the inputs that the process requires
Preconditions: the conditions that are required for the process to run
correctly
Results: a process may have different outcomes depending on some
condition
• Condition: under what condition the result occurs
• Outputs: the data that results from the execution of the process
• Effects: real world changes resulting from the execution of the process
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Semantic Web Services
Composite Processes
Composite Processes specify how processes work together to
compute a complex function
Composite processes define
1. Control Flow
Specify the temporal relations between the executions of the
different sub-processes
2. Data Flow
Specify how the data produced by one process is transferred to
another process
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Semantic Web Services
Example of Composite Process
Sequence
Airline
BookFlight
Control Flow Links
Flight
Specify order of
execution
Data-Flow Links
Specify transfer of data
Perform
Perform
Airline
Depart
Arrive
Get Flights
Flights
Flights
Select
Flight
Perform statements
Specify the execution of a process
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Flight
ISRI-Seminar-05
Semantic Web Services
Control Flow
Processes can be chained to form a workflow
OWL-S supports the following control flow constructs
Sequence/Unordered: to represent a list of processes that are
executed in sequence or random order
Conditionals: if-then-else statements
Loops: while and repeat-until statements
Multithreading and synchronization: split process in multiple
threads, and rendezvous (joint) points
Non-deterministic choices: (arbitrarily) select on process of a set
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Semantic Web Services
Data Flow
Dataflow allows information that is transferred from process to process.
OutputInput:
The information produced by one process is transferred to another in the same
control construct
Input Input:
The information received by a composite process is transferred to the sub-processes
OutputOutput:
The information produced by a subprocess is transferred to a super-process
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Semantic Web Services
Service Grounding
Service Grounding
Provides a specification of service
access information.
Service Model + Grounding give
everything needed for using the
service
Builds upon WSDL to define
message structure and physical
binding layer
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Semantic Web Services
Mapping OWL-S /WSDL 1.1
Operations correspond to
Atomic Processes
Input/Output messages
correspond to Inputs/Outputs
of processes
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Semantic Web Services
Example of Grounding
Airline
Sequence
BookFlight
Perform
Perform
Airline
Depart
Arrive
Get Flights Flights
Arrive
Depart Get Flights Op Flights
Airline
WSDL
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Flight
Copyright Katia Sycara
Flights
Select
Flight
Flight
Flights
Select
Flight op
Flight
ISRI-Seminar-05
Semantic Web Services
Result of using the Grounding
Invocation mechanism for OWL-S
Invocation based on WSDL
Different types of invocation supported by WSDL can be used with OWL-S
Clear separation between service description and
invocation/implementation
Service description is needed to reason about the service
• Decide how to use it
• Decide how what information to send and what to expect
Service invocation may be based on SOAP and XSD types
The crucial point is that the information that travels on the wire is the same
information used in the ontologies
Allows any web service to be represented using OWL-S
For example: Amazon.com
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ISRI-Seminar-05
Semantic Web Services
Mapping OWL-S to WSDL
OWL-S invocation is based on the Grounding
Map atomic processes into WSDL operations
Use XSLT to map between XML Schema data structures and
Ontological Information
Invocation procedure totally separated from semantic
description of Web service
• Invocation may be modified without changing semantic
description
Any Web service can be described in OWL-S without
modifying the WSDL description of the service
• Amazon’s Web service has been described in OWL-S
maintaining Amazon’s XML-Schema data types
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Semantic Web Services
OWL-S Virtual Machine
OWL-S VM a generic processor for the OWL-S Process Model
Uses OWL-S to represent service descriptions
It can interact with any OWL-S Web service
Based on the Process Model formal semantics (Ankolekar et al 2002)
Implements grounding mapping to WSDL
Uses OWL to represent information to exchange between Web services
Actively adopts logic inference to reason about OWL-S and OWL
ontologies
Exploits Web services technology such as Axis and WSIF for actual
invocation and message exchange
Anupriya Ankolekar, Frank Huch, Katia Sycara. "Concurrent Execution Semantics for DAML-S with
Subtypes." In The First International Semantic Web Conference (ISWC), 2002.
Massimo Paolucci, Anupriya Ankolekar, Naveen Srinivasan and Katia Sycara, "The DAML-S Virtual Machine," In
Proceedings of the Second International Semantic Web Conference (ISWC), 2003,
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Semantic Web Services
Architecture of CMU OWL-S VM
Web Services
SOAP
Provider
Web Service
Description
WSDL
OWL-S
Ground
ing
OWL-S VM
Webservice Invocation
Axis’s Web Service
Invocation Framework
OWLS
WebServiceInvoker
OWL-S Processor
Grounding Execution Rules
Process Model Execution Rules
OWL-S
Process
Model
OWL Inference Engine
OWL Jess KB
Jess
Jena
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Requester
APPLICATION
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Semantic Web Services
WSDL2OWL-S Converter
Provides partial conversion from WSDL Web service
descriptions to OWL-S descriptions
Generates complete specification of Grounding
Partial Specification of the Process Model
• Including Atomic Processes
Partial Model of the Profile
Resulting models require additional annotations to
include semantic descriptions
Combined with Java2WSDL to provide Java2OWL-S
Web Based Interface
http://www.daml.ri.cmu.edu/wsdl2owls/
Download: http://projects.semwebcentral.org/projects/wsdl2owl-s/
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Semantic Web Services
Process Model of AWS
•WSDL2OWL-S
used to generate
OWL-S for
Amazon’s Web
Service
•OWL-S VM used to
interact with
Amazon Web
service
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Shop
Search
Reserve
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Semantic Web Services
Performance
OWL-S VM
OWL-S VM client on
browsing+reserving task
Analyzed data by computing:
Time required by OWL-S VM to
execute Process Model
Time required for data
transformation to fit Amazon
requirements
Time required to invoke an
operation on Amazon
Data
Transformation
Amazon
Invocation
98 runs total over 4 days in varying load
conditions
Results in milliseconds
VM
Average
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Data Trsfm
Invocation
percentage
83
156
2797
3%
5%
92%
Strd dev
107
146
1314
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Autonomous Semantic Web Services
Problem of Composition
No single Web service may achieve all goals of an agent
Composition is the process of chaining results from different Web
services automatically
Planning problem
How do the Web services fit together?
Interoperation problem
How does the information returned fit together?
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Autonomous Semantic Web Services
CMU Composition Architecture
Exploits Retsina Architecture for WS composition
OWL-S/UDDI Matchmaker for discovery
Retsina planner to control the agent
• Use interleaving of planning and execution to allow communication while
planning
OWL Reasoner
OWL-S Virtual Machine to communicate and invoke Web Services
Katia Sycara, Massimo Paolucci, Anupriya Ankolekar and Naveen Srinivasan, "Automated
Discovery, Interaction and Composition of Semantic Web services," Journal of
Web Semantics, Volume 1, Issue 1, September 2003, pp. 27-46
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Autonomous Semantic Web Services
Example of Composition
Used in a number of applications:
travel domain, supply chain
management
Supports composition and execution
of Web Services
Connection with autonomous agent
technology
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in collaboration with
ISRI-Seminar-05
Semantic Web Services
Security and Policies
No standard OWL-S representation for Security and Policies has been published yet
But experimentation already under going
Adoption of a solution will depend on WS security standards
Security Experiments with
• representing security capability/requirements for discovery
• Representing security information in Process Model.
Policies:
Experiments combining OWL-S and Rei
Rei statements included in Process Model to constrain the use of a Web service (see Kagal 2004)
Recent work on Formal Verification of OWL-S Process Models provides a way to certify
adherence to a policy
Grit Denker, Lalana Kagal, Tim Finin, Massimo Paolucci, Naveen Srinivasan and Katia Sycara,
"Security For DAML Web Services: Annotation and Matchmaking" In Proceedings of the
Second International Semantic Web Conference (ISWC 2003), Sandial Island, Fl, USA, October
2003, pp 335-350.
Anupriya Ankolekar, Massimo Paolucci, and Katia Sycara
Spinning the OWL-S Process Model -- Toward the Verification of the OWL-S Process
Models In Proceedings of Workshop on Semantic Web Services:
Preparing to Meet the World of Business Applications (ISWC 2004)
57
Copyright Katia Sycara
ISRI-Seminar-05
Semantic Web Services
Production cycle of OWL-S WS
1.
2.
3.
4.
5.
6.
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Developer generates Java code
Semi-automated transformation of Java into partial OWL-S description
– WSDL is generate as by-product
User friendly OWL-S editor is used to complete the OWL-S description
UDDI client can be used for automatic advertisement in UDDI
Verification tools are available for correctness checking
Automatic client generation: integration with the OWL-S VM
Copyright Katia Sycara
ISRI-Seminar-05
CMU OWL-S IDE (Eclipse based)
OWL-S/UDDI
Matching Engine
OWL-S
Editor
UDDI
Client
Profile
Process
eclipse
Grounding
OWL-S Files
Java
Code
Legend:
OWL-S2UDDI
Converter
OWL-S
API
OWL-S
VM
Java
Code
Java
Code
Spin Based
Verification
Tools integrated in the OWL-S IDE
10/22/04
Data Files
Apache’s
Java2WSDL
Converter
UDDI-data
structure
WSDL
Code
WSDL2OWL-S
Converter
BBN’s
SWeDE
OWL Editor
http://projects.semwebcentral.org/projects/owl-s-ide/
59
Copyright Katia Sycara
ISRI-Seminar-05
Contributions of the three technologies
Semantic Web: ontologies, metadata annotations and
knowledge based inference
Multi Agent Systems: goal-directedness, semantically
meaningful communication protocols, cooperative and
self interested reasoning mechanisms
Web Services: industry standards and industry buy in
60
Copyright Katia Sycara
ISRI-Seminar-05
Future Evolution of Web Services
Semantic Web Services: services whose description is in
a machine understandable language with formal
semantics
Agent-based or Autonomous Semantic Web Services:
goal-directed
autonomous choice of partners
based on own current internal goals, internal
attitudes and their projection of their future needs.
semantics support ASWS
Semantic Web Services Interest Group created at W3C
public-sws-ig@w3.org
61
Copyright Katia Sycara