RE: Suggestions from Karsten Riemenr

[Martin W Sachs <mwsachs@us.ibm.com>]

Stefano,

While I agree with most of your comments, I would like to offer a somewhat
different view of these matters.

WSDL does not overlap the CPP/CPA at all.  Indeed, WSDL, as you say,  is a
way in which a Web Service advertises the way it can be accessed.  In the
ebXML world, this advertisement is effectively part of the BPSS instance
document that is referenced by the CPP and CPA.  More precisely, the
combination of WSFL and WSDL is architecturally equivalent to the BPSS
instance document in that the combination describes both the abstract
service interface and the choreography.  So, an ebXML BSI configured out of
a CPP plus Process-Specification document (the BPSS instance document)
reflects an interface including both the equivalent of the WSDL abstraction
and the concrete endpoint properties described in the CPP.

Since WSEL has not yet been exposed outside of IBM except for the four
letters and the very brief description in the WSFL specification, I can't
comment on its role at this time.  Given that the E stands for "endpoint",
an obvious inference can be made as to how it conceptually relates to
ebXML.

Regards,
Marty

*************************************************************************************

Martin W. Sachs
IBM T. J. Watson Research Center
P. O. B. 704
Yorktown Hts, NY 10598
914-784-7287;  IBM tie line 863-7287
Notes address:  Martin W Sachs/Watson/IBM
Internet address:  mwsachs @ us.ibm.com
*************************************************************************************



Stefano POGLIANI <stefano.pogliani@sun.com> on 06/27/2001 11:51:01 AM

To:   "Welsh, David" <David.Welsh@nordstrom.com>, Martin W
      Sachs/Watson/IBM@IBMUS, ebxml-cppa@lists.oasis-open.org
cc:
Subject:  RE: Suggestions from Karsten Riemenr



The idea of approaching the CPP/CPA with WSDL has been recurrent in some
discussions I recently had.

I just would like to add my 2 cents here, expressing my own position.

I think that WSDL and CPP/CPA have some area of overlap, which does not
mean
that, IMHO, they overlap.
The "area of overlap" is the area in which both the specifications aim to
define how a network component (the WebService or the BSI, according to the
different vocabularies used here) defines itself to other components. So,
in
my understanding:
     - WSDL is a way in which WebServices advertise the way in which
       they can be accessed.
       I apologize for the extreme simplification, but WSDL is a sort
       of API (in XML form) with binding infos
     - the CPP/CPA, **in addition to other things**, provides a
       similar "advertising" functionality but it is not API-oriented
       but is "business process" oriented.
       Instead of saying which are the "technical doors", the
       approach of the CPP/CPA is to expose the "logical doors",
       i.e. the doors "interpreted" in a business process context.

If this succint description makes sense, then I think that WSDL and CPP/CPA
tackle the problem in different ways (in addition of CPP/CPA doing more
than
this advertising, at least up to the state-of the WSDL specs). So, I think
that it would be very difficult to find a compromise on these different
approaches. It may be possible to "expose both interfaces" at the same
time,
perhaps.

I personally think that exposing "technical entry points" is a very minimal
approach, that is good for trivial WS such as currency-converters,
weather-forecasts and the like (which are the ones that are normally
mentioned in the literature, btw...). "technical entry points" do not
capture the "context", do not capture the information about the environment
(and, why not, the reasons) for which a WS is called.

I think that an ebXML BSI, configured out of a CPP, may "reflect" a
WSDL-like interface. But this could become much more useful when the whole
WSEL/WSFL picture will be in place.

/stefano

» -----Original Message-----
» From: Welsh, David [mailto:David.Welsh@nordstrom.com]
» Sent: 25 June 2001 16:58
» To: 'Martin W Sachs'; ebxml-cppa@lists.oasis-open.org
» Subject: RE: Suggestions from Karsten Riemenr
»
»
» Marty,
» It would be very useful if 1. was elaborated a little more.
» Couldn't 2 and 4 be tied to the same thing ? What's behind WSDL
» is then left to the individual organization to operate; ie. very
» elaborate system automation or semi-/manual efforts to create the
» web service. But WSDL appears very important.
» I'd suggest the BP jury is still out on should there even be a
» procedural 'BP language' like BPML/WSFL/XLANG, or should BP be
» more a declarative approach which probably resembles more of the
» real business world.
» -Dave
»
»
» > -----Original Message-----
» > From: Martin W Sachs [mailto:mwsachs@us.ibm.com]
» > Sent: Monday, June 25, 2001 7:40 AM
» > To: ebxml-cppa@lists.oasis-open.org
» > Subject: Suggestions from Karsten Riemenr
» >
» >
» > I have received the following suggestions from Karsten Riemer:
» >
» > 1. Use of the 'substitution' capability that was added to
» > BPSS at Vienna.
» > In
» > general this expands to how to have generic business
» > processes, and yet
» > have
» > easy to process specializations of those for the specific partners.
» >
» > 2. Alignment with WSDL. Generically this expands to how to
» > best register
» > the
» > metadata about a partner's capabilities relative to the BP and its
» > documents.
» >
» > 3. Alignment with other BP languages like BPML and WFSL. This
» > may seem like
» > more of a pure BP issue. But actually BPML may play an
» > important role in
» > describing what specifically a partner will do internally in
» > response to an
» > ebXML exchange. Generically this expands to how we apply XML
» > to the link
» > between b2b and EAI.
» >
» > 4. Specification of a Business Service Interface. ebXML phase
» > one shyed
» > away
» > from specificying the actual software architecture. We just
» > hinted that a
» > BSI
» > is configured with a CPP. Someone, probably in OASIS should
» > step up to this
» > task.
» >
» > Items 2 and 4 are clearly CPP-CPA issues.  Item 4 should be joint work
» > among CPPA, MSG, and BP.
» > I am less certain about items 1 and 3.  I look forward to
» > having Karsten
» > participate and explain.
» >
» >
» > Regards,
» > Marty
» >
» > **************************************************************
» > ***********************
» >
» > Martin W. Sachs
» > IBM T. J. Watson Research Center
» > P. O. B. 704
» > Yorktown Hts, NY 10598
» > 914-784-7287;  IBM tie line 863-7287
» > Notes address:  Martin W Sachs/Watson/IBM
» > Internet address:  mwsachs @ us.ibm.com
» > **************************************************************
» > ***********************
» >
»