Re: [soa-rm] FYI: BEA SOA Reference Diagram

[Francis McCabe <fgm@fla.fujitsu.com>]

Well, I think the issue here is what modeling concepts are required  
in order to model multiple services. The OSI stack does not need to  
mention the multiple parties because modeling communication does not  
require the modeling of the parties; it effectively only models the  
medium of communication.

For us, the issue will only arise if we need to model the  
relationships between services. For a straw man example, if sequence  
or other dependency was part of being a service then we would need to  
model services as resources.

I guess, my intuition is that service qua service is very much akin  
to communication as medium. Hence my phrase that service was an  
action boundary.

We spent many months in the W3C trying determine what a service  
really was; and although we did not use the phrase action boundary;  
we would have had we thought of it!

Frank


On May 18, 2005, at 11:06 AM, Duane Nickull wrote:

>
>
> Ken Laskey wrote:
>
>
>> The essence of a SOA is multiple services coming together to  
>> satisfy a set of needs.
>>
>
> This is the core point we have not reached consensus on yet.  This  
> is a well worded as can be so I would like to use this assertion as  
> a basis for the discussion.
>
> Thoughts:
>
> I would agree that "The essence of a SOA infrastructure is multiple  
> services coming together to satisfy a set of needs.  I do have  
> reservations about the concept of multiplicity of services being  
> used as a key metric to define SOA.
>
> Questions:
> 1. Is it necessary that there be more than one service in order  
> that SOA be SOA? 2. If yes to #1, is it necessary to call services  
> only in sequence?
>
> My gut feeling is that having multiple services is probably a given  
> for any specific implementation of SOA, however it is not a  
> requirements for something to be service oriented.  If I architect  
> one application and build it with a single service, service  
> description, policy set, (+ whateverElseGetsInTheReferenceModel),  
> is that service oriented architecture?  I think yes.
>
> I would fully support a reference architecture depicting multiple  
> services  being used either sequentially or in parallel, however  
> think that is a sub project best left for a dedicated sub committee.
>
> Duane
>
>
>>
>