From: Chiusano Joseph [mailto:chiusano_joseph@bah.com]
Sent: Friday, May 27, 2005 12:31
PM
To: SOA-RM
Subject: RE: [soa-rm] David
Linthicum Says: "ESB versus Fabric.Stop It!"
I think it is the same service in both
cases, but with different service context ("preferred" context and
"non-preferred" context).
Ah Peter! You've sparked a thought...
Three statements to frame the thought:
(1) A service description defines the functionality and operational
requirements (data model, semantics & policy) for interacting with a
service.
(2) Interacting with a service includes invocation or inquiry.
(3) It appears that we've determined that a service description is
independent of the *service*
Thus, is a service duplicative (and thus not truly service-oriented?)
when *any* part of that description changes? Or are two services the
same when the functionality/data models are static but the operational
requirements (and thus the metadata) differ?
A concrete example: Let's say there are two real-time ordering
services. Both offer the same functionality to whoever invokes them.
However, one is only available to preferred customers. A benefit of
preferential treatment is the guaranteed response times, represented by
the service policy. In addition, both services operate on a single
resource - the inventory data store.
Why are these two services distinct or duplicative? Does this mean that
functionality exposed in this manner is not service oriented?
Rebekah
Rebekah Metz
Associate
Booz Allen Hamilton
Voice: (703) 377-1471
Fax: (703) 902-3457
> -----Original Message-----
> From: Peter F Brown [mailto:peter@justbrown.net]
> Sent: Friday, May 27, 2005 11:42 AM
> To: 'Ken Laskey'; 'SOA-RM'
> Subject: RE: [soa-rm] David Linthicum Says: "ESB versus Fabric.Stop
It!"
>
> But surely if your service offer includes a better SLA,
faster
response
> time, better quality of result, etc. it is not a duplication of a
service
> but a different service: it may however use the same resources, and
that
> is
> a different issue...
>
> -Peter
>
> -----Original Message-----
> From: Ken Laskey [mailto:klaskey@mitre.org]
> Sent: 26 May 2005 02:44
> To: SOA-RM
> Subject: Re: [soa-rm] David Linthicum Says: "ESB versus Fabric.Stop
It!"
>
>
> On May 25, 2005, at 2:30 PM, Chiusano Joseph
wrote:
>
> >> -----Original Message-----
> >> From: Duane Nickull [mailto:dnickull@adobe.com]
> >> Sent: Wednesday, May 25, 2005 2:29 PM
> >> Cc: soa-rm@lists.oasis-open.org
> >> Subject: Re: [soa-rm] David Linthicum Says: "ESB versus
Fabric.Stop
> >> It!"
> >>
> >> The question that Rebekah asked that is tough and we need to
answer
> >> is "What is the opposite of Services". On other
words, if it is
not
> >> service oriented, what is it. This is a tough question and
our RM
> >> must address a level of clarity that we can point at something
that
> >> is not SOA as well as something that is.
> >>
> >> I would like to hear opinions on this.
> >
> > Duplication of services instead of sharing services: Not SOA.
> >
>
> This gets into the hairy realm of governance. I could argue that you
> should
> not be funded to develop a service because I provide adequate
> functionality.
> However, you may respond that my quality of service stinks and you'll
do
> better. On the other hand, I want to extend the functionality of
your
> service but to do that I will be duplicating everything you can do.
>
> This goes on and on.
>
> -1
>
> Ken
>
> > Kind Regards,
> > Joseph Chiusano
> > Booz Allen Hamilton
> > Visit us online@ http://www.boozallen.com
> >
> >> Duane
> >>
> >>
>
------------------------------------------------------------------------
> ------------------
> Ken Laskey
> MITRE Corporation, M/S H305 phone:
703-983-7934
> 7515 Colshire Drive
fax: 703-983-1379
> McLean VA 22102-7508
>
>
>