Re: WS-CDL or abstract BPEL

Dear all,

we hope to add a contribution to the discussion by introducing our work 
about choreography and orchestration. We had read the paper posted by 
Honda and we think the topic is strongly related to our interests. In 
Bologna, our group is investigating choreography and orchestration as 
complementary approaches for system design.  In particular, we consider 
choreography and orchestration as two different views of service 
oriented applications and that they can be both useful at the system 
design stage. We follow a formal approach and we are developing two 
process calculi for dealing with choreography and orchestration which 
can be used together for designing complex tasks. To this end, we have 
also developed a conformance notion (inpired to bisimulation) for 
testing the conformance between an orchestrated system and a given 
choreography.
We are very interested to continue a discussion about this topic. 
Interested readers can visit our web pages and download some papers 
about it. In particular next december the 15, Roberto Lucchi will 
present at ICSOC 2005 our work: "Choreography and Orchestration: a 
synergic approach for system design".

http://www.cs.unibo.it/~cguidi/
http://www.cs.unibo.it/~lucchi/

Best Regards ,

Claudio Guidi
Roberto Lucchi




Tonny Holdorf ha scritto:
>
> Hello everybody,
>
> I am totally new to this community, so please bear with me if I have 
> gotten something wrong.
>
> I am trying to get a view of the pros and cons of WS-CDL versus 
> abstract BPEL for modeling business collaborations and protocols. In a 
> thread on the Theserverside:
>
> http://www.theserverside.com/news/thread.tss?thread_id=37760
>
> Steve Ross-Talbot linked to the paper by Marco Carbone Kohei Honda and 
> Nobuko Yoshida. Reading the paper made me wonder if the WS-CDL and the 
> abstract BPEL work groups and specifications are pursuing the same 
> goal. Steve suggested that I post my questions here. So here they are:
>
> In the paper linked to above (i.e. the paper by Marco Carbone Kohei 
> Honda and Nobuko Yoshida) two formal calculi are described: a 'global' 
> calculus that models business processes from a global perspective and 
> the pi-calculus that models the same processes as a set of local 
> endpoint behaviors. The global calculus is similar to WS-CDL and the 
> main point of the paper is that processes modeled with the global 
> calculus (WS-CDL) can be translated to the pi-calculus.
>
> Reading the paper made me wonder: Why is a global description of the 
> service collaboration as in WS-CDL better than a set of local 
> descriptions that each describes the behavior of the participating 
> services (e.g. as a set of abstract BPEL descriptions)? Would a set of 
> abstract BPEL descriptions for each of the collaborating services and 
> a global WS-CDL description for the collaboration as a whole not just 
> be different representations of the same thing? If not, what 
> expressive power is added by the global WS-CDL description compared to 
> a set of abstract BPEL descriptions for each end point.
>
> Also, many complicated network protocols, e.g. TCP, have been 
> specified just fine by descriptions of endpoint behavior such as state 
> machines. Why is a global specification needed?
>
>
> Best Regards
>
> Tonny
>


-- 
_____________________________________________________________

  	dott. Claudio Guidi

  	Università di Bologna
  	Corso di Laurea in Scienze dell'informazione
  	via Sacchi, 3
  	47023 Cesena (FC), Italy

  	Phone:  +39-0547-338846
  	Fax:    +39-0547-338990

  	e-mail: cguidi@cs.unibo.it
_____________________________________________________________

Received on Monday, 5 December 2005 15:34:14 UTC