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Performability Models for Designing Disaster Tolerant Cloud Computing Systems
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Agenda
Motivation
Approach
Architecture
Perfomability
Sensitivity Analysis
Survivability Evaluation
GeoClouds Tool
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MOTIVATION
Why adopt cloud computing?
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Why adopt cloud computing?
Cloud computinginfrastructure is available on demand.
Adopted as a service.
Minimizes the costs of IT infrastructures
Service Level Agreement (SLA). Penalties may be applied if the defined availability level is not
satisfied
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Motivation
Large cloud service providers adopts service level agreements (SLAs) to regulate the availability of the cloud service.Costs
Availability
Performance (response time)
Service provider needs to carry out availability analysis
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Motivation
IaaS – computing resources in the form of virtual machines (VMs).
DisastersMultiple data located in different geographical locations
Availability improvement
VM migration time increases due to distance between data centers
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APPROACH
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APPROACH
Evaluate dependabilitycloud computing systems deployed into geographically distributed data
centers.
(RBD - Reliability Block Diagrams)
(SPN - Stochastic Petri Nets)
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ARCHITECTURE
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Architecture
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(SPN/RBD) BUILDING BLOCKS
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Hierarchical Modelling
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COMBINED MODEL
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Survivability Evaluation
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RTO and RPO Evaluation
RTO Model
RPO Model
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Results
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Sensitivity Analysis
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Results
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Results
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Geoclouds Modcs
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Validation
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Validation
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Conclusion
• Performability
• Survivability
• Tool
• Validation
• Sensitivity Analysis
Next Steps :
Write Papers
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Questions