R-GMA

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R-GMA OGSA23/7/2002

• James Magowan / IBM
• ltmagowan_at_uk.ibm.comgt

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Contributors

• Brian Coghlan TCD
• Andy Cooke Heriot-Watt
• Ari Datta QMUL
• Abdeslem Djaoui RAL
• Laurence Field PPARC
• Steve Fisher RAL
• James Magowan IBM-UK
• Werner Nutt Heriot-Watt
• Manfred Oevers IBM-UK
• Manish Soni PPARC
• Norbert Podhorszki STAKI
• John Ryan TCD
• Anthony Wilson PPARC
• Xiaomei Zhu PPARC

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OGSAfication of R-GMA
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R-GMA
Application Code
Consumer Instance
Consumer API
Registry API
Registry

• API Servlet communication
• http(s) in
• XML back

Schema API
Producer API
Registry API
Schema
Producer Instance
Sensor Code
Event Dictionary
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OGSA RGMA
Consumer Factory
Application
Consumer API
Registry
Consumer Instance
Producer Instance
Schema
Producer Factory

• All Grid Services
• OGSA Factories, GSH, GSR
• Registry includes HandleResolver
• SQL as Service Data Element Query Language
• lightweight api causes issues with lifetime
  management
• TerminationInterval.

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R-GMAification of OGSA
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OGSA v R-GMA

• OGSA
• NotificationSource
• NotificationSink
• Service Data
• NotificationSubscription
• FindServiceData

• R-GMA
• Producer
• Consumer
• Tables
• Streaming
• Query

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OGSA Notification
Consumer Factory
Grid Service A
Consumer (Sink)API
Registry
Consumer Instance
Producer Instance
Schema
Producer Factory

• Takes overhead and complication of notification
  away from your service
• Issues
• How does sink on A start source on B
• or source on B start sink on A?
• GSH removes need for Registry?

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Consumer/Producer

• R-GMA provides this ability
• See Page 41 of Grid Service Specification for
  what this means for OGSA

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Registry

• Anything useful exist?
• Yes - R-GMA
• Consider tables as large service data elements
• Service registers with certain fixed components
  to its service data elements
• Publishes full service data element to R-GMA
• Flexibility between dynamic and static service
  data elements.

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Registry

• Mediator
• Use power of SQL to identify subset of
  interesting services!
• Takes into account service data in registry
• extension take into account service data which
  only exist within service?
• Consumers continue to be notified of changes in
  the set of producers
• OGSA R-GMA issues
• Registry/Schema structures
• Topology for scalability, reliability etc.

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How to find us!

• http//hepunx.rl.ac.uk/edg/wp3/