Trading Grid Services in the UK e-Science Grid
description
Transcript of Trading Grid Services in the UK e-Science Grid
Trading Grid Services in the UK e-Science Grid
Steven Newhouse
Technical Director
London e-Science Centre
‘Marketplace for Computational Services’ project
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Market for Computational Services
• UK Core e-Science Programme project• Define interfaces & protocols to trade Grid Services• Funded by Department of Trade & Industry• Collaborators
– London e-Science Centre (LeSC)– e-Science North West (ESNW)– Southampton e-Science Centre (SeSC)– UK Grid Support Centre
Implementation of Current GESA Draft Specification
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OGSA
Infrastructure Architecture
OGSI: Interface to Grid Infrastructure
Data Intensive Applications for Science X
Compute, Data & Storage Resources
Distributed
Simulation, Analysis & Integration Technology for Science X
Data Intensive X Scientists
Virtual Integration Architecture
Generic Virtual Data Access and Integration Layer
Structured DataIntegration
Structured Data Access
Structured Data Relational XML Semi-structured-
Transformation
Registry
Job Submission
Data Transport Resource Usage
Banking
Brokering Workflow
Authorisation
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Grid Economic Services Architecture
OGSA Grid ServiceService InterfaceService Data
Service InterfaceService Data
OGSA ChargeableGrid Service
Grid EconomicService Interface
RecordResource
Usage
OGSAResource
UsageService
AgreementNegotiation
EconomicService
Data
AgreementVerification
ServiceCharging
OGSA GridPaymentService
GridUser/Actor
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Grid Economic Service Architecture
• GESA enabled client ‘obtains’ a GSH– Grid Service Handle (GSH) provides unique service ID– Represents a service & cost for use– Changes in price & status through new service & GSH
• GSH passed to an existing client– Retains existing client interface for economic services
• Key Issues:– Information needed to make the selection (SDE)– Two (Multi?) stage commit to support pricing– Enable wide ranging exploration of grid economic
models
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New Economic SDEs & Services
• Trust, Reputation & Reliability (0+)– Can I rely on this service? Will it deliver?– Has this service been audited for performance & integrity? – Allow SDE to updated by signed statements?
• Compensation & Liability (0+)– Who can I complain to and can I prosecute?– How could the contract be broken?
• Grid Payment Services (1+)– Declare which GPS are acceptable
• Resource Usage Service (1)– Declare which RUS is used by the service
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Exploratory Implementation
• Use of service specification documents developed within the project & GGF.
• Focus on core services:– Computational Grid Service (LeSC)– Resource Usage Service (eSNW)– Grid Payment Service (SeSC)
• Demonstrate through a Simple Maths service
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Simple Maths Service State diagram
SimpleMathsCGSFactory
UserAgent
RequestPricing
SDEs: Pricing, Trust,Reputation, etc.
RequestPricing
SimpleMathsCGS
SDEs: Pricing, Trust,Reputation, Cost etc.
AcceptPricing
SimpleMathsCGS
SDEs: Pricing, Trust,Reputation, Cost etc.
UseService
SimpleMathsCGS
SDEs: Pricing, Trust,Reputation, Cost etc.
TIM
E
ResourceUsage Service
Grid PaymentService
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Economically enabled Grid Service
Select a factory service to generate a service instance with which to initiate negotiations
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Examine Pricing Options
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Examine Offer
Examine the offer (‘terms & conditions’) and accept or decline.
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Browse Current Accounts…
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Use the Counter Service
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… on service destruction, cost calculated & money transferred…
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WS-Agreement Phases
• Stateless (agree on static items)– Pricing mechanisms (e.g. Fixed price)– Payment mechanism (e.g. HeyPounds on completion)
• Stateful (created by Factory)– Negotiate cost of each consumable quantity– Need ability to:
• Hold a reservation (for a specified period - negotiable)• Agree to a reservation (binding commitment)• ‘Fork’ negotiation (to explore different options)
– Support one shot or multiple iterations
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GESA Agreement Terms
• Pricing method– Enumeration of provider supported mechanisms
• Currency– Enumeration of provider supported mechanisms
• Cost– Floating point
• Consumable– Enumeration of items and their charging units– Use UR-WG quantities & rates?
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ICENI:IC e-Science Networked Infrastructure
The Iceni, under Queen Boudicca, united the tribes of South-East England in a revolt against the occupying Roman forces in AD60.
• Developed by LeSC Grid Middleware Group• Use to define and develop higher-level services• Collect and provide relevant Grid meta-data• Interaction with other frameworks: OGSI, Jxta etc.• Available under extended open source SISSL:
– http://www.lesc.ic.ac.uk/iceni
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CONTRACT CHAIN
INITIAL SERVICE LEVEL AGREEMENT
FABRIC
COMPUTERESOURCES
SOFTWARERESOURCES
STORAGERESOURCES
SERVICECONTRACT
SERVICECONTRACT
SERVICECONTRACT
CLIENTS (USERS)
Contract (SLA) Specified Services within ICENI
DefineCapability
DefineAccess
ExposeCapability
Modify, extend& restrict policy
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Information Capture & Utilisation
UserRequirements
Software & HardwareCapabilities
SoftwareComponentMeta-data
ResourceMeta-data
ApplicationStructure
SelectionPolicy
UserRights
Application asInteractive Service
Meaning
Implementation
Behaviour HardwareCharacteristics
UsagePolicy
ResourceState
CompositeApplication
Workflow Model
PerformanceModel
ExecutionPlan
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Conclusions
• Exploratory implementation of GESA– Validate use of OGSI for stateful services– Extend basic Grid Service with economic capability– Development of CGS, RUS, & GPS services
• Demonstrated use of GT3– Many problems expected from a new infrastructure
• Documentation, documentation, documentation
– See LeSC, eSNW & SeSC stands
• Next Steps– Develop & Refine current implementation– Engage in the definition & development of WS-Agreement
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Acknowledgements
• Development Teams– LeSC: Miqdad Asaria, William Lee, Anthony Mayer– eSNW: Jon MacLaren– SeSC: Kushan Nammuni
• Management Teams– LeSC: John Darlington, Steven Newhouse, Oliver Jevons– eSNW: John Brooke– SeSC: Simon Cox, Trevor Cooper-Chadwick
• http://www.lesc.ic.ac.uk/markets