Minutes of the Sixth OGSI-WG Teleconference
18/Sep/2002 @ 15:00-16:30 GMT

Attendees:

Tim Banks <IBM>
Karan Bhatia <Entropia>
Karl Czajkowski <ISI>
Shel Finkelstein <Sun>
Steve Graham <IBM>
Bill Horn <IBM>
Fred Maciel <Hitachi>
Andreas Savva <Fujitsu>
Frank Siebenlist <ANL>
David Snelling <Fujitsu>
Peter Vanderbilt <NASA>
Von Welch <ANL>

1) Minutes from 11-Sept-2002 were approved.

2) Report from Steve Tuecke on ServiceType Extension in WSDL 1.2

Steve reported that the meeting had gone well and that Service Type
extension (as we called it) will make it into WSDL 1.2. Here is a
summery of the details:

   1) There will not be a ServiceType element added to WSDL.
   2) PortTypes will be extendable by the inclusion of other
      portTypes.
   3) A single portType may be extended by more than one portType
      (multiple inheritance)
   4) The service element will refer to the most derived portType.

The disappearance of serviceType is in recognition that portType
extension makes this flat, single level aggregation mechanism
redundant. It also simplifies tool development, as it is more backward
compatible, and solves a binding problem with serviceTypes. The model
is "set union" of interface as we discussed in Chicago. There are
still some issues open with respect to how binding will function. They
are likely to adopt a very strong statement on mutability of portTypes
for the same reasons we discussed.

Steve thanked the interim meeting group for the brainstorming
session. He felt very confident and was able to refer to our
discussions on issues as the W3C discussed them - a case of deja vu
for Steve.

3) At GGF6 we will have one update meeting and three working
   meetings. There will be a gap after the update meeting on day 1,
   and two meetings back to back on day 2. We will also reserve the
   early morning slot on day 3, although not initially plan to use it.

4) Completed Actions

Action: Steve Graham to derive a way to say (as a simple type)
DateTime or "Forever" - Don (by PV)

The following was provided by Peter:

   <xs:simpleType name="infinityType">
     <xs:restriction base="xs:string">
       <xs:enumeration value="infinity"/>
     </xs:restriction>
   </xs:simpleType>
   <xs:simpleType name="extendedDateTime">
     <xs:union memberTypes="xs:dateTime gsdl:infinityType"/>
   </xs:simpleType>

----

Action: Shel, Dan, Steve G. to check the complexity of deserialization
of a DateTime or "Forever".

Report from Shel is that there isn't a problem as long as it is a
compond type (as proposed above). I'v marked this as done, but if
other toolers have a problem they should speak up soon.

----

Action: Steve Tuecke to devise language for qname resolution attribute
in instance SDEs. This has to do with wsdl schema Location.

Peter has put some text into the next draft. It will get reviewed in
due course. - Done (by PV)

----

Action: Steve Graham and Peter Vanderbilt to address #32 xsd:float use
is misleading. Done.

Our current approach is to make all the SDD "type" attributes refer to
element declarations, not type definitions.  In addition, we define
(in the gsdl namespace) some element declarations for OGSA entities.

5) Open Actions:

Action: Steve Graham to drive the creation of an XML Schema for the
specification, #35.

Action: Thomas Oinn to summarize the meaning of the presence/absence
of service data content.

Action: Shel Finkelstein to write a working definition of Client and
some case studies where QoS properties become critical.

Action: Steve Graham to craft language for recommendations to
developers for use of resolvers.

Action: Dave Snelling and Andrew Grimshaw to look at requirements and
solutions for pull like semantics.

Action: A. Grimshaw to see if the dissertation referred to can be
pushed to the whole mailing list.

6) Next Meeting:

Time:
  Wednesday, September 25th
     08:00-09:30 US Pacific (GMT - 7)
     09:00-10:30 US Mountain (GMT - 6)
     10:00-11:30 US Central (GMT - 5)
     11:00-12:30 US Eastern (GMT - 4)
     15:00-16:30 GMT
     16:00-17:30 UK (GMT + 1)
     17:00-18:30 Central Europe (GMT + 2)
     00:00-01:30 Japan

Place:
  Phone: Correct through GGF6.
	Phone number: 1-484-630-5376
	Pass code: 93031
  IRC:
     DALnet
     #ogsi

Technical Agenda:

   Notification Semantics:

      - What level of QoS are we going to expose in the Spec?
           Use cases:
                 - Heart beat
                 - Eventual notification of state change
                 - Once only notification of state change
                 - Work-flow control signals
                 - Exposure of database trigger functions.
                 - Globus style MDS management

      - Can higher level QoS functions (e.g. transaction, DB triggers)
        be built on this or will totally independent portTypes be
        needed to expose these semantics independent of binding?

      - "Deliver" Notification without a return may just mean "Forward
        or Post" Notification.
        Is this a case for two operations in the Sink portType?

      #43 The specialization of the DeliverNotification operation

      #44 Language linking notification subscriptions to SDEs.

      - Explore further the implications of subscriptions as Grid Services.

   Return semantics and Exceptions in the Spec.

      - What does a successful return from a RegisterService call?
        #42 The distinction between 'void return' and 'no return' in
         some operations

7) Open Issues:

      - Track the IPR status of WSIL.
      - Should WS-Inspection document (or other formats) be explicitly
        noted in the spec?
      - What assumptions can be made about the properties of a service
        resolved by a resolver?