Minutes of the Second OGSI-WG interim Meeting
14/Nov/2002

Attendees:

Karl Czajkowski <ISI>
Jeff Frey <IBM>
Steve Graham <IBM>
Bill Horn <IBM>
John Karpovich <Avaki>
Dean Lorenz <IBM>
Fred Maciel <Hitachi>
Jim Magowan <IBM>
Tom Maguire <IBM>
Jeff Nick <IBM>
John Rofrano <IBM>
David Snelling <Fujitsu>
Ellen Stokes <IBM>
Yih-Shin Tan <IBM>
Steve Teucke <ANL>
Jay Unger <IBM>
Peter Vanderbilt <NASA>

1) Approval of minutes from Nov 6 2002: - OK

2) Set Agenda:

   Adjourn at 15:00 Friday

   - WSDL 1.2 report and strategy
   - Strategy for development of the spec and timelines
   - Service Data
      - PortType representation of SD
      - Set operations
      - Style of representation of create etc.
   - Notification/Events
   - Registration
   - Exceptions
   - Bugzilla items
   
3) WSDL 1.2 report and strategy

W3C met this week. Scheduling: Next fall to recommendation. Only GGF perspective seemed to press for an early date. They
 may be looking more like a WSDL 2.0 strategy. Implications: Work to 1.1 or work from a December Draft or wait for 1.2. 
What we need: PT extension and open content in portTypes.

At present there is a leaning toward allowing name clashes causing either combining of operations or rising errors on 
signature mismatches. 

[Status of GT3 tooling discussion using WSDL4J have put SD in to the definitions level. For extension some compromise. 
We had a general discussion of similar development strategies. Tom M. pointed out that the server side implications 
extend fairly deeply into the system architecture.]

There may be a publish/subscribe and event models.

In, in/out, out, out/in were in WSDL 1.1, They are thinking of dropping the last two.

They may remove the message element to replace with schemas. The impact on GSS would be minor in any case.

4) Strategy for development of the spec and timelines

Resolved: Delay release to Feb 14, 2003 and treat GGF7 (in the middle of the public review process) as an educational 
process. 

Resolved: We hold another interim meeting Jan 22, 23, 24 in Chicago, asking the OGSA WG to move to the start of the week
. A video link to USC/ISI will be provided. 

Resolved: Move up the telecons by 30 minutes. No call on Nov. 27.

5) Service Data

Steve Graham: Walked through his proposal, but the addition of ref posed some problems.

Resolved: Accept SG's proposal with the following exceptions.

Discussion of ref: Posed some problems with multiple inheritance and is a parallel construct to inheritance. There was 
some concern that the absence of refs would cause an object explosion in the design space.

Resolved: Drop ref from SG's proposal. This implies adding an initial values section to the declaration. Section 3.8 
mostly goes away. Error if min/max occurs are valued.

Resolved: Delete serviceDecriptionOnly for assignable. Convert back to instance only boolean default false.

Discussion about the ServiceData as a projection of actual state of the service. E.g why are we making the distinction 
in the architecture. This discussion surrounded the "implied" state and the SD 'projection' of that state.

6) Service Data versus Service State

Discussion: The key problem centres around the fact that the GS model has the notion of "implicit" state (defined by or 
implicit in the semantics of the operations) of which Service Data is a "projection", but that this distinction is not 
explicit in the model and there is no way to express the difference in the interface (e.g. are the implicit state and 
its projection indistinguishable). This failing creates problems in creating stable models of the distributed systems 
built from Grid Services.

[Note: The above paragraph summarizes 4 hours of discussion.]

Proposal: We need to add the duality of service data/state to the model explicitly and an attribute to state that the 
SDEs are consistent with (indistinguishable from) the "implied" state as...