Using Transactional Workflow Ontology in Agent Cooperation
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Transcript Using Transactional Workflow Ontology in Agent Cooperation
Using Transactional
Workflow Ontology in
Agent Cooperation
J. Korhonen, L. Pajunen, and
J. Puustjärvi
Background
BRIEFS information extraction system
Analyses
Transaction research in WorkMan
Database
news articles for corporate actions
constraint used for workflow control
BriefsAgents – a multi-agent system
Ontology
used to access information
Built on top of BRIEFS database
Technology
Multi-agent system
(MAS)
FIPA agent
platform
Web services
SOAP,
WSDL, UDDI
WSFL
DAML+OIL ontology
DAML-S
BriefsAgents system
Multi-agent system
Ontology communication
Briefs database used for
information
FIPA-OS agent platform
Entity agents, Query
agents and Insert agent
Agent
Entity
Query
Insert
Org
Company
Deals
Deal
Person
Jobs
Entity agents as wrappers
Queries made using
several Entity agents
Problem: changes to
query protocol
Person
Workflow in Web Services
Web service offers operations
WSDL describes operations
lack
of expressiveness on workflows
XLANG, WSFL, and WSCL add
capabilities
Local and global models describe
individual services and composed system
Workflow Ontology 1/2
Directs agents own workflow
Internal
use
Describe communication protocol
Multi-agent
Describes how to use offered services
Dynamic
use
collaboration with unknown agents
Used to compose higher-level services
Workflow Ontology 2/2
Three entities
Message-oriented tasks
Agents
Control links concurrent
or sequential
Go,
and web services
fork, join, loop etc.
Data links to/from
blackboard
Named
data
<<frame>>
Task
Task type
Transaction type
Optional
Commit operation
Abort operation
Protocol type
2
0..*
<<frame>>
Control Link
Link type
Condition
<<frame>>
Data Link
Data name
Translation
2
0..*
Transactional Workflow 1/2
Transactions add reliability to the workflow
Different transaction models
For
example nested, option, saga models
May not be known beforehand for all agents
Tasks have a transaction model attribute
Optional
does not, model may also be ’none’
Commit operation, abort operation
Transactional Workflow 2/2
Special tasks
Start
transaction
End transaction
Useful for nested
transactions
End transaction
checks failures
Call
commit/abort
Start
Go
Start
Transaction
Go
Order
Tickets
End
Transaction
Abort
Commit
Commit
Order
Abort
Order
End
Transactional workflow in MAS
Agent internal structure
Agent workflows should
be available
In FIPA terms, a WMA
Web service workflows
should be available
Dynamic negotiation of
protocols
Combined transactions
also web services
Agent Framework
WMA
Agent
Workflow engine
State engine
Web service
interface
Conclusions
Workflow ontology enables agent systems
to collaborate dynamically
Transactional support needed in agent
systems and web services
Agent systems integrate with web services