Towards an Ontology of Services for DAML

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Towards an Ontology of Services for DAML
SRI DAML Team December 15, 2000
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Resource
Service
provides
supports
employs
implements
Signature
Protocol
Relation
Procedure

Atomic Procedure
Function
Composite Procedure
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Signatures Protocols

• Signature includes
• Schema (Names types of inputs / outputs)
• Binding patterns (acceptable bindings of inputs)
• Protocol includes
• Message protocol
• Formatting wrapping of inputs / outputs
• Interaction protocol
• Interaction patterns (a process spec)
• Together, they define an API for the Service
• Everything needed for an agent to access it

4
Service
supports
employs
implements
Signature
Protocol
Relation
satisfies
RelationalConstraint
Function
FunctionalDependency
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Relational Services

• Many Web information sources implement relations
  or functions (catalogs, tables, stock quotes,
  HTML forms, MapQuest, Travelocity, .)
• Relations/functions defined in the pure
  logical/mathematical/database sense are useful
  ways to characterize these information sources
• Functional dependencies (and other integrity
  constraints)
• Subclasses of RelationalService for SQL DB,
  Semi-structured DB, Forms Tables, etc.

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Procedures

• Many services produce state changes
• Services may change world state (Travelocity)
• Agents need state information during execution
• Agents need to know possible actions from a given
  state
• Interaction model specifies procedural service
• Atomic procedures
• Composite procedures are composed by
  instantiating process templates of various types

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Interaction Model

• Describes the meaningful patterns of messages
  that make up a Net transaction
• Specifies roles for 2 or more agents (buyer,
  seller)
• Is part of a Services Protocol spec
• Specified with a process-modeling language
• Agreed upon by all participants
• But each has its own copy of the model
• Represents the intersection of the process models
  of the participants

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An XML based Process Markup
lt?xml version "1.0"gt lt!DOCTYPE process SYSTEM
"process.dtd"gt ltprocess name "plan-trip"
created_by "srini" date "08082000 ltsequencegt ltta
sk name get-itinerary doc-create
itin.html address "http//www.travelocity.com
/reservation/"gt lt/task lttask name
"select_itinerary" doc_create "sorted.htmlgt
lttask name get_user_approval
ltwhile_dogt condition "status(user_select) !
"done" lttask name
"get_user_approval" display "sorted.html"gt
ltcondition condition
"status(user_select) "cancel"
lttask name "cancel-res" lt/terminategt
ltcondition condition status(user_select)
done lt/taskgt lttask name
make reservation lt/taskgt
lt/sequencegt lt/processgt A health care example


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The Travel Plan Demo