Re: granularity/definition of a "service" (fwd)

Hi!

I'm really not familiar with BPEL4WL, but one way to see this problem is 
a philosophy of ISs. 

The difference what is discussed here is the boundary between the 
representational and state-tracking world. The representational may have 
certain states, but those are not related in to the changes of states in 
the real world. In OWL the atomic processes are grounded to the actual 
state-tracking software while the other services among the control 
constructs are just containers for a set of services within a process. 

i.e. the model may have state itself (within a transaction), but 
the real world states are controlled through the atomic services 
(grounded to the actual programs). So in my opinion sending 
and receiving affect the state of the model, while atomic processes affect 
the state of the real world. 
 
Does this sound right to you?

- Tuukka Ruotsalo



On Thu, 16 Sep 2004, Monika Solanki wrote:

> 
> Hi All,
> 
> Keeping aside the "web" part, I am interested in understanding the 
> semantics of the word "service". Within the web service world, what is 
> the lowest level of granularity a service can have. What would be the 
> most appropriate definition for the basic building block from which 
> bigger units can be composed.  Services communicate via sending and 
> receiving messages. Can communication primitives also be classified as 
> services i.e in this context is it appropriate to consider the operation 
> of sending and receiving as services themselves and can they be modelled 
> as such ? The BPEL4WS specifies these and other control constructs as 
> "Activity". So in this context is a "service" at a higher level of 
> abstraction  then an "Activity" or do they have equivalent semantics.
> 
> -Monika
> **>><<**>><<**>><<**>><<**>><<**>><<**>><<**
> Monika Solanki
> Software Technology Research Laboratory(STRL)
> De Montfort University
> Gateway building, G4.61
> The Gateway
> Leicester LE1 9BH, UK
> 
> phone: +44 (0)116 250 6170 intern: 6170
> email: monika@dmu.ac.uk
> web: http://www.cse.dmu.ac.uk/~monika
> **>><<**>><<**>><<**>><<**>><<**>><<**>><<**
> 

Parhain terveisin,
Best Rergards,

Tuukka Ruotsalo
email. turuotsa@st.jyu.fi

Received on Thursday, 16 September 2004 14:39:37 UTC