Re: Dubray paper comments + questions

Jean-Jacques Dubray wrote:
> [JJ] Typically I am a believer of a collaboration protocol (internal or
> external) rather than using correlation using message elements. I find
> them clumsy though necessary, until collaboration protocols are used
> widely. 

The need for correlation is related to asynchronicity. If you are going 
to decouple request and response, you need a way of associating response 
with request. The initiator could issue multiple requests, and the 
responder may return responses to any of these in an unpredicatable 
order. (This may not be a common or familiar use case if you are 
accustomed to synchronous request-reply, but it is usually how things 
work with asynchronous protocols).


> [JJ] Sorry, I corrected, the end tag was meant to be DataFlow. Again,
> the whole purpose of the paper was not necessary to detail the process
> definition but rather to show the concepts and how they are related to
> each other. (If there is an interest I can publish a more robust spec).
> A separate data flow is proposed by BPSS and WSFL. BPML has a very good
> data flow too.

Ok ... one of the reasons I'm asking about this, and about BPEL4WS, is 
that if this proposal is going to be taken seriously as an alternative 
to other schemes, then IMO it has to be complete enough to compare with 
other, more fully specified alternatives. The existing specs have flaws, 
but their capabilities and limits are also easier to grasp.

--Jon

Received on Wednesday, 26 February 2003 12:16:47 UTC