Re: question: relation between WS-CDL and WSCI

Hi Assaf,
Thanks a lot for clarifying some things...still some questions in-line.

----- Original Message -----
From: Assaf Arkin <arkin@intalio.com>
To: Titi Roman <dumitru.roman@deri.ie>
Cc: Steve Ross-Talbot <steve@enigmatec.net>; WS-Choreography List
<public-ws-chor@w3.org>
Sent: Tuesday, April 13, 2004 11:14 PM
Subject: Re: question: relation between WS-CDL and WSCI


> >I am a little bit confused here...In the WSCI 1.0
> >(http://www.w3.org/TR/wsci/) in section 1.6.2 it says that WSCI "is
> >declarative and cannot, by itself, be executed." (I also haven't heared
> >about amy execution environments for WSCI). I understood that WSCI
possess
> >an operational semantics, did you refer to this when you said that WSCI
was
> >an executable language?
> >
> >
> WSCI was definitely not intended to be executable, but describe the
> observable message exchange between the participants. It did focus on a
> level of abstraction that some other proposals would consider

Which are these other proposals(I am just trying to understand what you
meant by "any language can be viewed as operational compared to a more
abstract language")?

> "operational", but any language can be viewed as operational compared to
> a more abstract language.
>
> >Why do you need a formalism in the choreography context (where can be
seen
> >the usefulness of using such a fomalism for a choreography language)?
Where
> >is it actually needed?
> >
> >
> Formalism allows you to make a lot of proofs about the language itself,
> but more interesting, about the specifications you produce using that
> language. In the case of WSCI, formalism becomes more important as a way
> to derive conclusions about compositions, and it allows you to leverage
> the extensive work done in the field of process calculus.

Does these mean that WSCI is really dead (as Steve Ross-Talbot pointed out
in one of his emails)?

As far as I understood and please correct me if I am wrong, WS-CDL supports
only "global model"(i.e. the multi-participant view of the overall message
exchange) - this sounds to me as a static linking between web services. What
about the dynamic linking between ws from the point of view if
coneversation? What about the view of the overall message exchange as seen
from one participant? Isn't WS-CDL supposed to support also this view?

In this context still my previuos questions:

Where exactly is pi-calculus used in WS-CDL and what scenarios by using
pi-calculus in this context do you predict?

When you choosd pi-calculus as the underlying fromalizm for WS-CDL, I
suppose you had some reasons for choosing it and not other
formalisms...could you point out shortly these reasons?

Thanks a lot!
Titi Roman

Received on Thursday, 15 April 2004 04:17:15 UTC