Couple of relevant papers FWIW

An analysis of BPEL (might help to position it with BPSS)
http://www.ebpml.org/bpel4ws.htm

Comparison of BPML & BPEL

http://www.ebpml.org/A_Comparison_of_XPDL_and_BPML_BPEL.doc


Cheers,

-Suresh
Sterling Commerce (on loan to RosettaNet)



-----Original Message-----
From: Paul Prescod [mailto:[email protected]]
Sent: Thursday, October 03, 2002 2:55 PM
To: Ugo Corda
Cc: 'Champion, Mike'; [email protected]
Subject: Re: Article on WS architecture and best practice ... may be of
in terest



Ugo Corda wrote:
>>this methodology
>>defeats the whole purpose of Web services, which is to hide the
>>implementation of a service completely behind an XML-based interface. 
>>VS.NET generates the interface from the implementation.
> 
> 
> I don't see the conflict here. For any user of the Web service the
generated
> interface does exactly that: hides the original implementation.
> 
> If the point made by the article is that Web services interfaces should be
> defined first and implementations should follow, this is evidently not
> possible in all those cases where Web services are used as wrappers for
> legacy implementations.

I think that the point is that the web service's interfaces should be 
designed to make it into a good network application which could be 
radically different than the appropriate interfaces for a LAN-based or 
desktop software component for all of the reasons described in the 
"Waldo paper" and elsewhere. If you are just letting software "generate" 
your network interface from a pre-existing interface then the chances it 
is optimal as a network application is tiny.

  Paul