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Trading Grid Services in the UK e-Science Grid. Steven Newhouse Technical Director London e-Science Centre ‘Marketplace for Computational Services’ project. Market for Computational Services. UK Core e-Science Programme project Define interfaces & protocols to trade Grid Services
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Trading Grid Services in the UK e-Science Grid Steven Newhouse Technical Director London e-Science Centre ‘Marketplace for Computational Services’ project
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
Infrastructure Architecture Job Submission Brokering Workflow Structured Data Integration Registry Banking Authorisation Data Transport Resource Usage Transformation Structured Data Access Structured Data Relational XML Semi-structured - Data Intensive X Scientists Data Intensive Applications for Science X Simulation, Analysis & Integration Technology for Science X Generic Virtual Data Access and Integration Layer OGSA OGSI: Interface to Grid Infrastructure Compute, Data & Storage Resources Distributed Virtual Integration Architecture
Grid Economic Services Architecture Grid User/Actor Service Data Service Interface Grid Economic Service Interface OGSA Grid Payment Service Agreement Verification Agreement Negotiation Economic Service Data Service Charging OGSA Resource Usage Service Record Resource Usage OGSA Chargeable Grid Service Service Data Service Interface OGSA Grid Service
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
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
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
Simple Maths Service State diagram Request Pricing SDEs: Pricing, Trust, Reputation, Cost etc. SimpleMaths CGS Request Pricing Accept Pricing SimpleMaths CGS SDEs: Pricing, Trust, Reputation, Cost etc. Use Service SimpleMaths CGS SDEs: Pricing, Trust, Reputation, Cost etc. Resource Usage Service Grid Payment Service SimpleMaths CGSFactory SDEs: Pricing, Trust, Reputation, etc. User Agent TIME
Economically enabled Grid Service Select a factory service to generate a service instance with which to initiate negotiations
Examine Offer Examine the offer (‘terms & conditions’) and accept or decline.
… on service destruction, cost calculated & money transferred…
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
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?
ICENI:ICe-Science Networked Infrastructure • 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 The Iceni, under Queen Boudicca, united the tribes of South-East England in a revolt against the occupying Roman forces in AD60.
Contract (SLA) Specified Services within ICENI CLIENTS (USERS) Modify, extend & restrict policy CONTRACT CHAIN Expose Capability SERVICE CONTRACT SERVICE CONTRACT SERVICE CONTRACT Define Access INITIAL SERVICE LEVEL AGREEMENT COMPUTE RESOURCES SOFTWARE RESOURCES STORAGE RESOURCES FABRIC Define Capability
Information Capture & Utilisation User Requirements Software & Hardware Capabilities Software Component Meta-data Selection Policy User Rights Application Structure Resource Meta-data Meaning Behaviour Hardware Characteristics Resource State Usage Policy Implementation Composite Application Workflow Model Performance Model Execution Plan Application as Interactive Service
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
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