abstraction layers n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Abstraction Layers PowerPoint Presentation
Download Presentation
Abstraction Layers

Loading in 2 Seconds...

play fullscreen
1 / 10

Abstraction Layers - PowerPoint PPT Presentation


  • 79 Views
  • Uploaded on

Abstraction Layers. Why do we need them? Protection against change Where in the hourglass do we put them? Computer Scientist perspective Expose low-level services Use SOAP as a wire protocol? Working Scientist perspective Want high-level services Use C/C++/Java APIs

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Abstraction Layers' - lane


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
abstraction layers
Abstraction Layers
  • Why do we need them?
    • Protection against change
  • Where in the hourglass do we put them?
    • Computer Scientist perspective
      • Expose low-level services
      • Use SOAP as a wire protocol?
    • Working Scientist perspective
      • Want high-level services
      • Use C/C++/Java APIs
      • Opaque Service & Interaction Handles
what services abstractions do we need
What Services / Abstractionsdo we need?
  • Look at some projects:
    • CLRC e-Science Centre
    • AstroGrid
    • MyGrid
    • ICENI
    • OGSA
clrc e science centre
CLRC e-Science Centre
  • Single sign-on authentication
  • Security service
  • Authorisation
  • Additional user services (including local user management)
  • Resource discovery service
  • Workspace creation service
  • 3rd party file transfer facility
  • XML parser service
  • Query generation
  • Replication
  • Data source discovery
  • Results collation
  • Dynamic resource monitoring
  • Event handling services
  • Messaging service
  • Job submission
  • Job monitoring
  • Visualisation
  • Computational steering
  • Thesaurus service
  • Ontology service.
astrogrid
AstroGrid

VO=Virtual Observatory

mygrid services
MyGrid Services
  • User Agent & Repository
  • Notification
  • Workflow: Personalisation, Resolution, Enactment & Serialisation
  • Databases & Distributed Query
  • Job Scheduling & Resource Management
  • Information Extraction
  • Authentication
  • Service Directory
  • User, Group & Roles Directory
  • Workflow Provenance & Repository
  • Ontologies – Service function & metadata
iceni
ICENI
  • Low-level services
    • Computational
    • Storage
    • Software
    • Networking
  • High-level services
    • Application composition to define workflow
    • Scheduling (mapping components to resources)
    • Throughput (resource brokering)
ogsa 17 2 02
OGSA (17/2/02)
  • Is a Grid Service also a Web Service?
    • YES as it has ports (described in WSDL) for:
      • Grid Service (Introspection & termination)
      • Notification Source & Sink
      • Registration of Grid Service Handles
      • Service creation (factory)
      • Primary Key (map key to GSH)
      • Mapping (map GSH to GSR)
    • BUT can only be deployed in an OSGA compatible hosting environment
  • Is a Web Service also a Grid Service?
    • NO as it ‘misses’ out on the extra capability
    • BUT can be deployed within an OGSA environment
ogsa services
OGSA Services
  • Low-level services
    • Execution, file transfer & service meta-data (?)
  • Higher-level services
    • Distributed Data Management
    • Work flow
    • Auditing
    • Instrumentation & monitoring
    • Problem determination (e.g. dump, trace & log)
    • Security protocol mapping
common requirements
Common Requirements?
  • Low-level:
    • Security
    • Execution
    • Database Access
    • Data movement
    • Service Management
  • High-level:
    • Workflow management (Scheduling)
    • Usage & Access Policy
    • Notification (Events & Messaging)