SLA Negotiation in AssessGrid WSAgreement Implementation with Globus Toolkit

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SLA Negotiation in AssessGridWS-Agreement
Implementation with Globus Toolkit

• Kerstin Voss
• Paderborn Center for Parallel Computing (PC²)
• University of Paderborn

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Agenda

• Key aspects of SLAs in AssessGrid
• 1st Prototype Negotiation implementation
• 2nd Prototype Modified negotiation
• Summary

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WS-Agreement
SLAs
1st Prototype
2nd Prototype
Summary

• Context
• General information
• Service Terms
• What service should be provided?
• Guarantee Terms
• obligations for provider or user
• Penalty fees

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SLAs in AssessGrid
SLAs
1st Prototype
2nd Prototype
Summary

• parallel or single-jobs in a Computational Grid
  are considered
• number of compute nodes
• earliest start time
• latest finish time
• Resource Management System used is
  planning-based (OpenCCS)
• execution duration has to be specified
• AssessGrid specific
• Probability of Failure for an SLA

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Scenario 1 User Provider Neg.
SLAs
1st Prototype
2nd Prototype
Summary

• Fill Template
• Job description
• Max. PoF
• Min. Penalty

Get Template
SLA Request
Commit
Contract
SLA Offer
Create Offer - Set Price
RMS Resource Management System PoF
Probability of Failure
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Scenario 2a Broker Mediator
SLAs
1st Prototype
2nd Prototype
Summary
Get Templates
Template Subscription
RMS Resource Management System
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Scenario 2a Broker Mediator
SLAs
1st Prototype
2nd Prototype
Summary
SLA Request
SLA Offer
RMS Resource Management System
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Scenario 2a Broker Mediator
SLAs
1st Prototype
2nd Prototype
Summary
Commit
Contract
RMS Resource Management System
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Scenario 2b Broker Contractor
SLAs
1st Prototype
2nd Prototype
Summary
Contract
Contract
RMS Resource Management System
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Problem in 1st Prototype
SLAs
1st Prototype
2nd Prototype
Summary

• End-user sends the provider an SLA request
• Provider makes a tentative reservation and
  generates an SLA offer
• End-user might accept or reject this SLA offer
• ? Tentative reservations are blocked execution
  times for other SLA requests

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Modified SLA-Negotiation Process
SLAs
1st Prototype
2nd Prototype
Summary

• Prevents vulnerability of Denial of service
  attacks

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Summary
SLAs
1st Prototype
2nd Prototype
Summary

• SLAs in AssessGrid are defined for jobs in a
  Computational Grid
• WS-Agreement implementation was modified
• getQuote and createAgreement realises that
• Provider makes no tentative reservations?
  prevents vulnerability of DoS attacks
• AgreementInititator is end-user

Thanks for your attention!
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Consortium - www.assessgrid.eu