Filtering

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Filtering Selecting Semantic Web Services with
Interactive Composition Techniques
By Evren Sirin, Bijan Parsia, and James Hendler
Presenting By Mirza Tania Nasreen
Mohammad Hasan
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Outline of the Presentation

• Main Idea of the Paper
• Works done by Authors
• Relevant Terms
• Comparisonal Work Flow
• Technology Used
• Implementation details
• Conclusion

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Main Idea of the Paper
Composition of Web Services
Dynamically
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Why Composition ???

• Goal applications will be able to communicate
  each other very flexibly to achieve some combined
  and new functionality from existing ones.

• Present Condition failed to achieve this goal

• the expected ability to compose web services has
  not been achieved yet

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Works Done by the Authors

• Developed
• goal-oriented
• interactive composition approach

• Implemented
• In a Prototype system

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Web Service

• Web Service is a software system designed to
  support interoperable Machine to Machine
  interaction over a network. W3C
• A web service is a collection of protocols and
  standards used for exchanging data between
  applications or systems. Wikipedia

Current State of SOA
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Drawback with Example
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Semantic Web Service

• a services whose properties, capabilities,
  interfaces, and effects are encoded in an
  unambiguous, machine-understandable form.

World Wide Web
Web Service
HOW WEHERE
Semantic Web
Semantic Web Service
WHAT WHY
Web Service Semantics Semantic Web Service
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Why Semantics ????

• (Discovery) Neither WSDL nor UDDI allows for
  software to determine what a Web service offers
  to the client. A Semantic Web service describes
  its properties and capabilities so that software
  can automatically determine its purpose.

• (Invocation) A Semantic Web service provides a
  descriptive list of what an agent needs to be
  able to do to execute and fulfill the service.
  This includes what the inputs and outputs of the
  service are.

• (Monitoring) services can interoperate with each
  other seamlessly and can combine results for a
  valid solution.

Dynamic Composition
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Why Semantics? An Example
French to English Dictionary
string
string
string
string
word
translated word
word
meaning
WS 2
WS 1
translated English word
meaning
French word
What Why
What Why
Semantic Annotation is the main concept behind
Dynamic Composition
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How Semantics ????

• UDDI

Standards for Service Directory

• WSDL

Standards for Description

• SOAP

Standards for Messaging Protocols
WSDL OWL-S Semantic Web Service Description
First System to directly combine the OWL-S
semantic service descriptions with actual
invocations of the WSDL descriptions.
Dynamic Composition
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Major Focuses of the Paper
Filtering and Selecting Semantic Web Services
with Interactive Composition Techniques

• Filtering
• Selecting
• Interactive Composition Techniques

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Filtering

• Filter is designed to examine each input or
  output request for certain qualifying criteria
  and then process or forward it accordingly.

• When a service goes into the composition, this
  services information about input, output,
  preconditions, and effects (IOPE) serves to
  automatically filter the services whose outputs
  are incompatible with the current selection.

• Filtering helps to determine the service that
  best fits users/clients personal preferences.

• Filtering for their tool done by using
  matchmaking algorithms

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Selecting
Human Controlled
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Interactive Composition

• Gradually generates the composition with a
  forward or backward chaining of services.

• At each step, their system adds a new service to
  the composition and filters further possibilities
  based on the current context and user decisions.

Filtering Selecting Interacting Compositing
Techniques

• A successful, executable composition correctly
  combines a set of compatible components to
  achieve the compositions overall goal.

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Step-by-step Composition
Monitoring
Fixing a GOAL
Auto. Filtering
Filtering
List of Services
Select 1st web Service
Selecting
Selection
Select 2nd web Service
Compose 2 web services
Manual Composition
Dynamic Composition
Partial Automation of Composition
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Creating Semantic Service Description OWL-S

• OWL Enables greater access only to content
• OWL-S ( formerly DAML-S) Enables greater access
  to the Web Services
• OWL-S partitions a Web Services description into
  three components
• 1. Service Profile
• - IOPE parameters
• - service parameter
• 2. Process Model
• -Atomic Process
• -Composite Process
• 3. Grounding
• -Mapping from OWL-S to WSDL

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Translation from WSDL to OWL-S

• WSDL Operation OWL-S Atomic Process
• WSDL message parts OWL-S Processs Parameters
• Difficulties with Type Conversion
• Message parts are described by XML Schema data
  types
• OWL itself permits only a subset (constrained
  range) of XML Schema data types (integers /
  strings).
• OWL references data types by URI
• No canonical way in XML Schema to determine a URI
  for a complex data type
• Preferred Solution Parameter types of OWL-S
  services be OWL classes

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Translation from WSDL to OWL-S contd

• Authors Solution
• Treated the WSDL-supplied types as descriptions
  of the service parameters
• i.e. the serialization of the values the process
  actually uses.
• Extended the OWL-S grounding to include
  marshaling and unmarshaling functions using XSLT
• Unmarshalling function XML Schema type to an
  RDF graph serialized in the RDF/XML exchange
  syntax
• That graph encodes the relevant assertions about
  the individual, which becomes the actual input to
  the service
• Difficulties
• Its difficult to write XSLT that can handle all
  the legal serializations of a given RDF graph.

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Implementation
The Prototype System
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Implementation

• 4 Types of IOPE Matching
• Exact If advertisement A and request R are
  equivalent concepts
• PlugIn If request R is a subconcept of
  advertisement A
• Subsume If request R is a superconcept of
  advertisement A
• Fail No match.

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Matching IOPE

• Only IO was used for matching
• Specifications of PE are still an open OWL-S
  issue
• Exact and Plug-In matches between the parameters
  of ServiceProfiles yields useful results
• Returns an ordered list

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Matching Service Parameters

• To get rid of long list of available choice
• Service names themselves might not contain enough
  information
• Means of introducing more user constraint
• Applies the result of this new query to the
  previous result set

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Matching Service Parameters
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Generating and Executing Composed Services

• Generation
• Each Composition OWL-S CompositeProcess
• It can also be advertised, discovered, and
  composed with other services
• Generates exactly such a CompositeProcess
  description
• Creates the corresponding ServiceProfile
• Execution
• Invoking each individual services and passing the
  data
• Client program serves as the central control
  authority

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Improvement and further automation

• Strong need for a suitable set of service
  descriptions of sufficient and compatible detail
  to support
• Converting the IO type descriptions from XML
  Schema data types to OWL classes
• Removing human interaction from the loop by
  integrating a planner
• Introduce machine learning better and preferred
  suggestions

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Conclusion
Web Service
Semantic Web
Semantic Web Service
Maturity Hill
Partial Automation of Composition
Full Automation
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References

• Filtering and Selecting Semantic Web Services
  with Interactive Composition Techniques. IEEE
  Intelligent Sytems. 19(4) 42-49 (2004).
• Semantic Web Services. IEEE Intelligent Systems,
  Volume 16 Issue 2, March-April 2001, Pages 46
  -53
• Semantic Web Service Architecture EvolvingWeb
  Service Standards toward the Semantic Web.
  American Association for Artificial Intelligence
  (www.aaai.org).
• Bringing Together Semantic Web and Web Services.
  Proceedings 1st International Semantic Web
  Conference (ISWC 02), 2002.
• http//www.w3.org/Submission/OWL-S/

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Thank You ...