[ogsa-wg] OGSA-MWS-BOF at GGF14 on Tues June 28, noon-1:30

[Dave Berry]

Marty,

The reason I asked about the status of the specifications was to clarify
what sort of profile document could be produced at the present time.
OGSA profiles are governed by a set of rules
(https://forge.gridforum.org/projects/ogsa-wg/document/draft-ggf-ogsa-pr
ofile-definition/en/12).  Currently, if a group were to publish a
profile document, it would have to be an Informational Profile.  It
could not be a Recommended Profile because the specifications are not
yet in a standards body.  Of course, this does not preclude people
working on a draft profile with the intent of moving it into the
publication process at some later date.

I suggest that a question for the BOF to discuss is, given the above
process, at what point does it become worth spending time on a draft
profile?  (I am not presuming an answer to this question one way or
another).


Switching to the question of WS-Enumeration, your answer seems to
validate my initial concern.  The issue that WS-Enumeration attempts to
address is real and is considered in part by various working groups in
the data area, but to me it doesn't seem part of a basic profile.  Of
course, the fact that I haven't seen a technical reason that links
WS-Enumeration closely to the other specs doesn't mean that such a
reason doesn't exist!

Dave. 


-----Original Message-----
From: owner-ogsa-wg at ggf.org [mailto:owner-ogsa-wg at ggf.org] On Behalf Of
Marty Humphrey
Sent: 22 June 2005 12:45
To: 'Ogsa-Wg'
Subject: RE: [ogsa-wg] OGSA-MWS-BOF at GGF14 on Tues June 28, noon-1:30



> 1.  Please could you clarify the status of WS-Transfer, WS-Eventing 
> and WS-Enumeration in the terms of the OGSA Profile template?  I.e. 
> have they been submitted to an SDO, are they draft or evolving, etc.?

As you know, there is a 4-step process by which these specs will become
standards: [1] "Develop", in which the spec is published; [2] "Broader
Participation", in which there are feedback and interop workshops
(resulting in possibly revising and republishing the specs); [3]
"Standardization", in which the specs are submitted to a standardization
body, which then can modify the spec as well and eventually ratify; [4]
"Profiles", in which a separate document shows how to *combine* specs,
generally resulting in a "subsetting" of the original specs.

On Dec 1, 2004, Intel hosted a "feedback" workshop (step [2]), above,
for WS-Enumeration and WS-Transfer. The companies attending the workshop
included AMD, Computer Associates, Dell, HP, IBM, Intel, Microsoft, SAP,
Sharp, Sonic, Sun, veritas, et. al. Although I can't entirely confirm
this, it looks like the following companies brought implementations of
WS-Enumeration/WS-Transfer to this workshop: Microsoft, Dell, Intel,
NetIQ, Sun, and WebMethods.

On Feb 19, 2004, Tibco hosted a "feedback" workshop for WS-Eventing.
Attendees included Microsoft, BEA, IBM, NEC, Sonic, etc. On April 15,
2004, Microsoft hosted an "interop" workshop on WS-Eventing ("The
outcome of the workshop was the demonstration of interoperability among
all the 7 implementations." The seven implementations were from BEA,
Canon, Epson, Microsoft, Ricoh, Sonic, and Systinet.) It looks like
there will be another WS-Eventing workshop, although the date/time have
not been announced.

The most recent specs are:

-- WS-Eventing: Aug 2004 (Authors: IBM, BEA, Computer Associates,
Microsoft, Sun, and Tibco).  This new version modifies the original
version (Jan 2004, I believe) to reflect the workshops.

-- WS-Enumeration: Sept 2004 (Authors: Systinet, Microsoft, Sonic, BEA,
Computer Associates). This is the first version of the spec.

-- WS-Transfer: Sept 2004 (Authors: Systinet, Microsoft, Sonic, BEA,
Computer Associates). This is the first version of the spec.

There's an interesting graphic that shows some of the progress from
Microsoft's perspective here:
http://msdn.microsoft.com/webservices/graphics/workshop-timeline.gif
(this is taken from
http://msdn.microsoft.com/webservices/community/workshops/default.aspx)


> 2.  I can see that WS-Transfer specifies some of the functionality of 
> WSRF and WS-Eventing is largely equivalent to WS-BaseNotification, but

> what has WS-Enumeration to do with this?  From a brief reading, it 
> seems to specify functionality that is independent of either stack.

I can see this point -- in our initial designs and experimentation with
WS-Transfer and WS-Eventing, we chose to not utilize WS-Enumeration. But
we are increasingly considering WS-Enumeration as an important part of
the story. 

>From Felipe Cabrera of Microsoft: "Many scenarios require data exchange
using more than just a single request/response message pair. Types of
applications that require these longer data exchanges include database
queries, data streaming, the traversal of information such as
namespaces, and enumerating lists. Enumeration, in particular, is
achieved through establishing a session between the data source and the
requestor. This session is established using the Enumerate operation,
which provides an enumeration context that is then used in subsequent
operations. Successive messages within the session transport the
collection of elements being retrieved. No assumptions are made on the
approach used by the service to organize the items that will be
produced. What is expected is that under normal processing
circumstances, the enumeration will produce all the underlying data
before the end of the session.... In its simplest form, WS-Enumeration
defines a single operation, Pull, which allows a data source, in the
context of a specific enumeration, to produce a sequence of XML elements
in the body of a SOAP message.... Three more request/response operations
are defined in WS-Enumeration: Renew, GetStatus, and Release.... State
information regarding the progress of the iteration can be maintained
between requests by either the data source or the consuming service....
In addition to enumerating the data entities present in a Web service,
it is convenient to be able to perform several basic operations on them.
These operations are introduced in the WS-Transfer operation." 

I hope this helps,
Marty

Marty Humphrey
Assistant Professor
Department of Computer Science
University of Virginia