GGF10 - OGSA-WG Session 3
=========================

* Data Services: Impact of WS-Resource Framework, Allen Luniewski

  - Outline of changes needed to move from an OGSI based definition to a
    WSRF one. 
    - GSH replaced by EPR
    - WS-Resource definition changes
    - Lifetime
    - Factory as pattern, etc
  - Mainly "syntax" (expression) rather than semantics; basic concepts
    (virtualized access) have not changed.

** Discussion
  
  - GSH/GSR mapping replaced with endpoint references (EPR) or
    renewable references (RR). So far have been relying on multiple
    GSH-GSR mappings. Can something similar still be done that is
    transparent to the client?
   
    1. Include some opaque (to the client) information in EPR (e.g.,
       replica manager provides a new EPR based on opaque data?)
    2. Take advantage of RR to provide multiple mappings.

  - Workflow connection (e.g., to deliver computation results --- PE)
    - Some basic facility may be possible using composition

  - Composition for deployment service (CDDLM)
    - CDDLM serializes operations (to some extent) to make sure things
      are set up correctly
  
  - Naming
    - Data service as container; name is higher level concept.

  - Level of detail in OGSA document now and upcoming deadline for
    final draft (GGF11) --- only 10 weeks left.
    - What level of detail is needed: Interface definitions not in
      OGSA.
    - Who will use the document.
    - Big problem is that the current OGSA Data Services document does
      not define an architecture! How and by which process should the
      architecture be defined.
    - There is obviously a lot of work that still needs to be done.
    - Continue discussion of this issue offline.

* OGSA Information Services, Hiro Kishimoto

  - A number of different information services, Logging, Message
    Broker, Directory Services, use common platform interfaces:
    producer/consumer.
  - Treat as different patterns
    - extend vs use relationships
  - Logging service definition
  - Need for (ogsa) event definition 
  - Different aspects of messaging.

** Discussion

  - Need to explore relation between the OGSA producer/consumer and
    WS-N producer/consumer interfaces. Understand how they can be
    composed together.
    - OGSA interfaces are probably extensions of the WS-N interfaces.
    - Are they separate interfaces or not? Pull out commonality. But
      minimum requirement is composability.

  - Producer/consumer pattern seems to repeat often. Does it lead to
    anything more than just a description of an interesting pattern?
    - Useful exercise in taxonomy section to canonicalize patterns for
      description. Not clear if it leads to code.

* GMA based information service: Producers and Consumers, Abdeslem Djaoui
  
  - Some kind of information service needed for discovery monitoring.
  - Building on GMA producer/consumer
  - Discovery separated from information transfer.
  - Directory holds information on producers & consumers. Allows for
    producers and consumers to discover each other.
  - Key difference with WS-N: producers can also find consumers

** Questions/Comments  

   - Is directory i/f internal or external?
     - Internal and not standardized within OGSA.
   - Directory can be collection of services.
   - Notion of subscriber and consumer is bundled together.