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Subject: Re: [soa-rm] Definition(s) of "service"


Ken:

Thank you for owning this!  Good luck next week.

May I suggest that the Editors use the WIKI page during their meeting?

Duane

Ken Laskey wrote:

> Duane,
>
> I hate to say this (and my fellow co-editors may disagree) but I think 
> the task needs to be taken on by the editing team as a whole.  My SOA 
> mailbox has over 2300 messages with many threads having a bearing on 
> this, and even a cursory scan will be a significant effort.  Also, as 
> the current designated editor for the service section, I don't see a 
> good way of just dumping it onto someone else.
>
> I would be willing to be talked out of this position.
>
> Ken
>
> At 12:25 PM 8/9/2005, Duane Nickull wrote:
>
>> I would like to request a volunteer or volunteers to own this issue 
>> and ensure that none of the depth of this conversation is lost.  We 
>> have passed around heaps of good thoughts.  The owner would 
>> essentially be responsible for capturing the views / opposing views 
>> and keeping documentation up to date as this gets discussed.  The 
>> owner would not be entitled to simply gloss over with their own point 
>> of view but would act much like an editor - reflecting the consensus 
>> or the TC or noting the lack thereof.
>>
>> Anyone interested in owning this?
>> Duane
>>
>>
>>
>> Frank McCabe wrote:
>>
>>> I strongly resist the tendency of equating service with the 'back end
>>> capability' (or whatever). This is a dangerous and non-scalable
>>> direction to go in:
>>>
>>> 1. The implementation of a service is none of the service consumer's
>>> business.
>>> 2. The service consumer should not even be able to figure out how a
>>> service is delivered. If it can, then you will get security risks 
>>> and/ or scalability issues
>>> 3. A given capability may not be fully exposed in a given service
>>> 4. A given service provider agent may not *have* the capability
>>> offered in its service -- it may know someone who knows ... it may
>>> not be possible to characterize the capabilities of a service provider.
>>> 5. From the point of view of the service consumer, fundamentally, it
>>> cannot (normally) distinguish the surface aspects of interacting with
>>> a service and the deeper aspects that rely on the service's
>>> realization (e.g. this is an Oracle database so be careful with your
>>> SQL)
>>>
>>> On the other hand, the service consumer interacts with a service in
>>> order to achieve an effect. In most interesting cases this is a 
>>> 'real- world effect'. The consumer is interested in the fact that 
>>> the bank
>>> account has been credited.
>>>
>>> Interestingly, these real world effects can *also* be expressed in
>>> public semantic terms -- without relying on representing the internal
>>> state of the resource. For example, a bank customer wants to know
>>> that his or her account has a certain balance. This is a fact that is
>>> warranted by the bank; not simply by the database resource that the
>>> bank happened to use to store the account information. I.e., there is
>>> a public 'on-the-wire' assertion that the bank attests whenever a
>>> authorized request (again, note the on-the-wire nature of this) is
>>> made to the appropriate bank service.
>>>
>>>
>>> Frank
>>>
>>>
>>> On Aug 8, 2005, at 3:02 PM, Chiusano Joseph wrote:
>>>
>>>>> -----Original Message-----
>>>>> From: Ken Laskey [mailto:klaskey@mitre.org]
>>>>> Sent: Monday, August 08, 2005 5:50 PM
>>>>> To: soa-rm@lists.oasis-open.org
>>>>> Subject: RE: [soa-rm] Definition(s) of "service"
>>>>>
>>>>> As appeared earlier in this thread, there are contexts in
>>>>> which it is not necessary to discriminate between the
>>>>> capability and the service that accesses it,
>>>>
>>>>
>>>> Ken, are you equating capability with resource? I recall a  
>>>> reference to
>>>> resource that fits the above description, but not one to capability.
>>>>
>>>> Joe
>>>>
>>>> Joseph Chiusano
>>>> Booz Allen Hamilton
>>>> O: 703-902-6923
>>>> C: 202-251-0731
>>>> Visit us online@ http://www.boozallen.com
>>>>
>>>>
>>>>> and our
>>>>> discussion of service can make this clear.  However, I think
>>>>> this thread has also shown ample examples of where the
>>>>> service and the capability are clearly separate concepts and
>>>>> where it may be useful to allow that difference to be
>>>>> captured.  For example, it is likely for someone to ask if
>>>>> two services are the same.  While we do not address that
>>>>> particular question, it is far simpler to handle if we know
>>>>> whether the underlying capability is the same than if we
>>>>> obscure that difference at first principles.
>>>>>
>>>>> Ken
>>>>>
>>>>> At 05:03 PM 8/8/2005, Chiusano Joseph wrote:
>>>>>
>>>>>>> -----Original Message-----
>>>>>>> From: Frank McCabe [mailto:frank.mccabe@us.fujitsu.com]
>>>>>>> Sent: Monday, August 08, 2005 12:10 PM
>>>>>>> To: Ken Laskey
>>>>>>> Cc: soa-rm@lists.oasis-open.org
>>>>>>> Subject: Re: [soa-rm] Definition(s) of "service"
>>>>>>>
>>>>>>> This is going in a weird direction.
>>>>>>> I believed that there was significant consensus that the
>>>>>>
>>>>> notion of
>>>>>
>>>>>>> service that we are interested in *is* the
>>>>>>> interface/boundary/offering.
>>>>>>>
>>>>>>> The capability behind the service -- that which makes the service
>>>>>>> possible -- is private and out of bounds. That capability
>>>>>>
>>>>> is, by the
>>>>>
>>>>>>> way, best described using agent terminology.
>>>>>>
>>>>>>
>>>>>> Respectful non-concur. IMHO, the service *is* the
>>>>>
>>>>> capability, and the
>>>>>
>>>>>> service *has* an interface through which interaction with that
>>>>>> capability may be possible.
>>>>>>
>>>>>> Joe
>>>>>>
>>>>>> Joseph Chiusano
>>>>>> Booz Allen Hamilton
>>>>>> O: 703-902-6923
>>>>>> C: 202-251-0731
>>>>>> Visit us online@ http://www.boozallen.com
>>>>>>
>>>>>>
>>>>>>> Frank
>>>>>>>
>>>>>>> On Aug 8, 2005, at 8:50 AM, Ken Laskey wrote:
>>>>>>>
>>>>>>>
>>>>>>>> This is good because it highlights the bits of
>>>>>>>
>>>>> confusion we have
>>>>>
>>>>>>>> to explain our way around.
>>>>>>>>
>>>>>>>> The user interface is the facade through which the user
>>>>>>>
>>>>>>> interacts with
>>>>>>>
>>>>>>>> a service (i.e. inputting information/requests, viewing
>>>>>>>> results) but there may be delivery capabilities that
>>>>>>>
>>>>> are invoked
>>>>>
>>>>>>>> through relevant services and the delivery capabilities are the
>>>>>>>> mechanisms through which results are packaged and sent to the
>>>>>>>> requester/consumer.  For example, if I make a request for
>>>>>>>
>>>>>>> an image and
>>>>>>>
>>>>>>>> as part of that request, information about my connectivity is
>>>>>>>> provided, logic (capability) can be executed (possibly
>>>>>>>
>>>>>>> invoked through
>>>>>>>
>>>>>>>> a service) to decide which delivery mechanism is most
>>>>>>>
>>>>> appropriate
>>>>>
>>>>>>>> (e.g. high res or low res, what kind of compression, ...).
>>>>>>>>
>>>>>>>> Ken
>>>>>>>>
>>>>>>>> At 11:18 AM 8/8/2005, Michael Stiefel wrote:
>>>>>>>>
>>>>>>>>
>>>>>>>>> Actually, I think two things are being confused here.
>>>>>>>>>
>>>>>>>>> There is one service being used by several different
>>>>>>>>
>>>>>>> applications.
>>>>>>>
>>>>>>>>> The user interface (i.e. the actually delivery mechanism)
>>>>>>>>
>>>>>>> is not part
>>>>>>>
>>>>>>>>> of the service, or strictly speaking part of the SOA.
>>>>>>>>>
>>>>>>>>> Michael
>>>>>>>>>
>>>>>>>>> At 10:43 AM 8/8/2005, Ken Laskey wrote:
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>> I'd have to think about this further but in general I
>>>>>>>>>
>>>>>>> would say yes.
>>>>>>>
>>>>>>>>>> The underlying capability is making pizza and offering
>>>>>>>>>
>>>>>>> the product
>>>>>>>
>>>>>>>>>> for sale.  The mechanisms for accessing the capability are in
>>>>>>>>>> person, by phone, online.  Note, the capability existed
>>>>>>>>>
>>>>>>> before there
>>>>>>>
>>>>>>>>>> was online ordering and this is just another
>>>>>>>>>
>>>>> mechanism to access
>>>>>
>>>>>>>>>> a capability that already existed.
>>>>>>>>>> Interestingly from an orchestration/choreography sense,
>>>>>>>>>
>>>>>>> the delivery
>>>>>>>
>>>>>>>>>> of the pizza (in person pickup, delivery service from
>>>>>>>>>
>>>>>>> pizza place,
>>>>>>>
>>>>>>>>>> third-party delivery (e.g. Takeout Taxi around
>>>>>>>>>> here)) constitutes another set of capabilities that can
>>>>>>>>>
>>>>>>> have service
>>>>>>>
>>>>>>>>>> interfaces and can be combined in response to invoking
>>>>>>>>>
>>>>>>> the ordering
>>>>>>>
>>>>>>>>>> service.  All of these can be used for delivery of things
>>>>>>>>>
>>>>>>> other than
>>>>>>>
>>>>>>>>>> pizza (even the pizza place might also deliver sandwiches).
>>>>>>>>>>
>>>>>>>>>> I think part of the confusion is that a *physical*
>>>>>>>>>
>>>>>>> delivery service
>>>>>>>
>>>>>>>>>> is a millennia-old, longstanding capability that has
>>>>>>>>>
>>>>>>> nothing to do
>>>>>>>
>>>>>>>>>> with SOA and is *not* the service in the SOA sense
>>>>>>>>>
>>>>> but it uses a
>>>>>
>>>>>>>>>> different aspect of the S word.
>>>>>>>>>>
>>>>>>>>>> Ken
>>>>>>>>>>
>>>>>>>>>> At 07:11 PM 8/7/2005, joe@pantella.net wrote:
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>> Does this imply that if I order a pizza online vs. order a
>>>>>>>>>>> pizza over the phone vs. order a pizza by walking into the
>>>>>>>>>>> store, that these are all separate services?
>>>>>>>>>>>
>>>>>>>>>>> --JJP
>>>>>>>>>>>
>>>>>>>>>>> -----Original Message-----
>>>>>>>>>>> From: Ken Laskey [mailto:klaskey@mitre.org]
>>>>>>>>>>> Sent: Thursday, August 04, 2005 12:35 PM
>>>>>>>>>>> To: soa-rm@lists.oasis-open.org
>>>>>>>>>>> Subject: RE: [soa-rm] Definition(s) of "service"
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> This gets back to the previous discussion when we
>>>>>>>>>>
>>>>> talked about
>>>>>
>>>>>>>>>>> resources, i.e to what extent the service is the
>>>>>>>>>>
>>>>> mechanism to
>>>>>
>>>>>>>>>>> access (possibly coordinate) capability vs. when is it
>>>>>>>>>>
>>>>>>> considered
>>>>>>>
>>>>>>>>>>> the capability itself.
>>>>>>>>>>>
>>>>>>>>>>> I think any consideration of the service as the
>>>>>>>>>>
>>>>>>> capability/resource
>>>>>>>
>>>>>>>>>>> should be very limited.
>>>>>>>>>>>
>>>>>>>>>>> Ken
>>>>>>>>>>>
>>>>>>>>>>> At 11:07 AM 8/4/2005, Chiusano Joseph wrote:
>>>>>>>>>>>
>>>>>>>>>>>>> -----Original Message-----
>>>>>>>>>>>>> From: Ken Laskey [mailto:klaskey@mitre.org]
>>>>>>>>>>>>> Sent: Thursday, August 04, 2005 11:04 AM
>>>>>>>>>>>>> To: Chiusano Joseph; soa-rm@lists.oasis-open.org
>>>>>>>>>>>>> Subject: RE: [soa-rm] Definition(s) of "service"
>>>>>>>>>>>>>
>>>>>>>>>>>>> Somehow saying service *provides* capabilities
>>>>>>>>>>>>
>>>>>>> misses the SOA
>>>>>>>
>>>>>>>>>>>>> motivation to provide an effective way to bring together
>>>>>>>>>>>>> the
>>>>>>>>>>>>
>>>>>>>>>>> parts I
>>>>>>>>>>>
>>>>>>>>>>>>> need to solve a problem.  Integration is often
>>>>>>>>>>>>
>>>>> of disparate
>>>>>
>>>>>>>>>>> parts
>>>>>>>>>>>
>>>>>>>>>>>>> that exist for their own purposes.  Service can help
>>>>>>>>>>>>
>>>>>>>>>>> coordinate but
>>>>>>>>>>>
>>>>>>>>>>>>> the challenge is to make use of the tools/resources/
>>>>>>>>>>>>
>>>>>>>>>>> capabilities
>>>>>>>>>>>
>>>>>>>>>>>>> that already exist, not to create new stovepipes.
>>>>>>>>>>>>
>>>>>>> Saying the
>>>>>>>
>>>>>>>>>>>>> service provides all this is a tempting
>>>>>>>>>>>>
>>>>> simplification but
>>>>>
>>>>>>>>>>>>> I
>>>>>>>>>>>>
>>>>>>>>>>> fear it
>>>>>>>>>>>
>>>>>>>>>>>>> will trivialize the concepts most in need of
>>>>>>>>>>>>
>>>>> clarification.
>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Agree - and I should clarify that I was merely saying that a
>>>>>>>>>>>
>>>>>>>>>>> service
>>>>>>>>>>>
>>>>>>>>>>>> provides capabilities (in general). Combining a
>>>>>>>>>>>
>>>>>>> capability here, a
>>>>>>>
>>>>>>>>>>>> capability there, here a capability, there a capability,
>>>>>>>>>>>
>>>>>>>>>>> everywhere a
>>>>>>>>>>>
>>>>>>>>>>>> capability (oops sorry - that's the EIEIO song), we
>>>>>>>>>>>
>>>>>>> have composite
>>>>>>>
>>>>>>>>>>>> capabilities.
>>>>>>>>>>>>
>>>>>>>>>>>> Joe
>>>>>>>>>>>>
>>>>>>>>>>>> Joseph Chiusano
>>>>>>>>>>>> Booz Allen Hamilton
>>>>>>>>>>>> O: 703-902-6923
>>>>>>>>>>>> C: 202-251-0731
>>>>>>>>>>>> Visit us online@ http://www.boozallen.com
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>> Ken
>>>>>>>>>>>>>
>>>>>>>>>>>>> At 10:35 AM 8/4/2005, Chiusano Joseph wrote:
>>>>>>>>>>>>>
>>>>>>>>>>>>>>> -----Original Message-----
>>>>>>>>>>>>>>> From: Ken Laskey [mailto:klaskey@mitre.org]
>>>>>>>>>>>>>>> Sent: Thursday, August 04, 2005 10:18 AM
>>>>>>>>>>>>>>> To: soa-rm@lists.oasis-open.org
>>>>>>>>>>>>>>> Subject: RE: [soa-rm] Definition(s) of "service"
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> I'd still like to emphasize service as the access to
>>>>>>>>>>>>>>> capabilities for which there are extra-service
>>>>>>>>>>>>>>
>>>>>>>>>>> motivations for
>>>>>>>>>>>
>>>>>>>>>>>>>>> their existence and requirements for use of the
>>>>>>>>>>>>>>
>>>>>>>>>>> capabilities
>>>>>>>>>>>
>>>>>>>>>>>>>>> that must be
>>>>>>>>>>>>>>
>>>>>>>>>>>>> navigated
>>>>>>>>>>>>>
>>>>>>>>>>>>>>> by the service.  Thus,
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> "A service is a mechanism to enable access
>>>>>>>>>>>>>>
>>>>> to a set of
>>>>>
>>>>>>>>>>>>> capabilities,
>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> I would say that access control mechanisms enable such
>>>>>>>>>>>>>
>>>>>>>>>>>>> access, and that
>>>>>>>>>>>>>
>>>>>>>>>>>>>> the service *provides* the capabilities. Note: Use of
>>>>>>>>>>>>>
>>>>>>>>>>>>> "access control"
>>>>>>>>>>>>>
>>>>>>>>>>>>>> is too concrete for our RM - I stated it only to
>>>>>>>>>>>>>> illustrate
>>>>>>>>>>>>>
>>>>>>>>>>>>> the point.
>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Joe
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Joseph Chiusano
>>>>>>>>>>>>>> Booz Allen Hamilton
>>>>>>>>>>>>>> O: 703-902-6923
>>>>>>>>>>>>>> C: 202-251-0731
>>>>>>>>>>>>>> Visit us online@ http://www.boozallen.com
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> where the access is provided using a prescribed
>>>>>>>>>>>>>>
>>>>>>>>>>> interface and is
>>>>>>>>>>>
>>>>>>>>>>>>>>> exercised consistent with constraints and policies as
>>>>>>>>>>>>>>
>>>>>>>>>>>>> specified by
>>>>>>>>>>>>>
>>>>>>>>>>>>>>> the service description."
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Ken
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> At 11:15 PM 8/3/2005, joe@pantella.net wrote:
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Just trying to sort through this; some common themes
>>>>>>>>>>>>>>>
>>>>>>>>>>>>> that seem to
>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> be
>>>>>>>>>>>>>>>> acceptable:
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> A service provides capabilities.
>>>>>>>>>>>>>>>> A service is accessible. (If this is true, then
>>>>>>>>>>>>>>>> service
>>>>>>>>>>>>>>>
>>>>>>>>>>>>> cannot be a
>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> verb.) A service has an interface. (If this is true,
>>>>>>>>>>>>>>>
>>>>>>>>>>> then a
>>>>>>>>>>>
>>>>>>>>>>>>>>> service has
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> a boundary.) A service interface is
>>>>>>>>>>>>>>>
>>>>> prescribed. (Then
>>>>>
>>>>>>>>>>>>>>>> a
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> service and its
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> interface are distinct, and the interface has
>>>>>>>>>>>>>>>
>>>>>>>>>>> associated rules.
>>>>>>>>>>>
>>>>>>>>>>>>>>>> I'm not sure this is true, the interface may
>>>>>>>>>>>>>>>
>>>>>>> describe the
>>>>>>>
>>>>>>>>>>>>>>>> rules,
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> but Im not
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> sure it has rules.  In fact, I'm inclined to
>>>>>>>>>>>>>>>
>>>>>>> suggest that
>>>>>>>
>>>>>>>>>>>>>>> the interface
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> defines the rules for accessing the service.  Which
>>>>>>>>>>>>>>>
>>>>>>>>>>>>> would lead me
>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> to suggest that the service interface is more than a
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> specification of the
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> data model, but also of the policies
>>>>>>>>>>>>>>>
>>>>> associated with
>>>>>
>>>>>>>>>>>>>>>> the
>>>>>>>>>>>>>>>
>>>>>>>>>>>>> service.)
>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> A service is a set of behaviors.  (Not sure I'm on
>>>>>>>>>>>>>>>> board
>>>>>>>>>>>>>>>
>>>>>>>>>>>>> with this,
>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> something about behaviors doesn't sit well.)
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Given this, perhaps something like:
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> "A service is a bounded set of capabilities that are
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> accessible through
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> a prescribed interface."
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> -- JJP
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> P.S. I think this definition might just be
>>>>>>>>>>>>>>>
>>>>>>> flexible enough
>>>>>>>
>>>>>>>>>>>>>>> to navigate
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> the service offer/contract discussion also.
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> -----Original Message-----
>>>>>>>>>>>>>>>> From: Schuldt, Ron L [mailto:ron.l.schuldt@lmco.com]
>>>>>>>>>>>>>>>> Sent: Thursday, July 28, 2005 12:32 PM
>>>>>>>>>>>>>>>> To: Frank McCabe; SOA-RM
>>>>>>>>>>>>>>>> Subject: RE: [soa-rm] Definition(s) of "service"
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Frank,
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> While I believe that the previously proposed
>>>>>>>>>>>>>>>
>>>>>>> definition is
>>>>>>>
>>>>>>>>>>>>>>> sufficient,
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> I offer the following as a compromise.
>>>>>>>>>>>>>>>
>>>>> Hopefully, the
>>>>>
>>>>>>>>>>> notion of
>>>>>>>>>>>
>>>>>>>>>>>>>>>> "capabilities" addresses your issue of
>>>>>>>>>>>>>>>
>>>>> needing to get
>>>>>
>>>>>>>>>>>>> things done.
>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> "A service is a set of behaviors to provide
>>>>>>>>>>>>>>>> capabilities
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> accessible via
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> a prescribed interface."
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Ron
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> -----Original Message-----
>>>>>>>>>>>>>>>> From: Frank McCabe
>>>>>>>>>>>>>>>> [mailto:frank.mccabe@us.fujitsu.com]
>>>>>>>>>>>>>>>> Sent: Thursday, July 28, 2005 10:10 AM
>>>>>>>>>>>>>>>> To: SOA-RM
>>>>>>>>>>>>>>>> Subject: Re: [soa-rm] Definition(s) of "service"
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> I hesitate to spoil this party ... but I'm
>>>>>>>>>>>>>>>
>>>>> going to :)
>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> 1. There is a distinction between action and result.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>> (Just ask any
>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> roboticist) Behaviour sounds a child
>>>>>>>>>>>>>>>
>>>>>>> misbehaving with no
>>>>>>>
>>>>>>>>>>>>>>>> discernible effect. Computer Scientists have a
>>>>>>>>>>>>>>>> tendency
>>>>>>>>>>>>>>>
>>>>>>>>>>>>> to focus on
>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> the purely technical aspects of their work: bytes
>>>>>>>>>>>>>>>
>>>>>>>>>>>>> shuffling around
>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> at random within hopefully enormous memories.
>>>>>>>>>>>>>>>> 2. Also, we have to bear in mind that nobody invests
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> millions of $s (or
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> even 100's of them) in systems that
>>>>>>>>>>>>>>>
>>>>> contemplate their
>>>>>
>>>>>>>>>>> navels
>>>>>>>>>>>
>>>>>>>>>>>>>>> or have no
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> business payoff. I think that we have to directly
>>>>>>>>>>>>>>>
>>>>>>>>>>> address the
>>>>>>>>>>>
>>>>>>>>>>>>>>>> reason that services are deployed. 3. One of the
>>>>>>>>>>>>>>>
>>>>>>>>>>> movitating
>>>>>>>>>>>
>>>>>>>>>>>>>>>> best practice aspects of SOAs is
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> that clarity
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> and 'separation' between the providers of
>>>>>>>>>>>>>>>
>>>>>>> services and the
>>>>>>>
>>>>>>>>>>>>>>> consumers of
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> services leads to more scalable and robust
>>>>>>>>>>>>>>>
>>>>>>> architectures.
>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> All of the above is fuzzy language; but, at the
>>>>>>>>>>>>>>>
>>>>>>> same time,
>>>>>>>
>>>>>>>>>>>>>>> "A service
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> is a set of behaviors accessible via a prescribed
>>>>>>>>>>>>>>>
>>>>>>>>>>> interface."
>>>>>>>>>>>
>>>>>>>>>>>>>>>> sounds a lot like bureauspeak.
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> I believe that there is strong consensus on the
>>>>>>>>>>>>>>>
>>>>>>> following
>>>>>>>
>>>>>>>>>>>>>>>> characteristics:
>>>>>>>>>>>>>>>> a. The concept of service is 'at the
>>>>>>>>>>>>>>>
>>>>> boundary' between
>>>>>
>>>>>>>>>>> service
>>>>>>>>>>>
>>>>>>>>>>>>>>>> providers and consumers. b. The service is
>>>>>>>>>>>>>>>
>>>>>>> 'there' to get
>>>>>>>
>>>>>>>>>>>>>>>> things done; but doesn't
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> itself denote
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> the engine that performs the tasks.
>>>>>>>>>>>>>>>> c. There is a reason for using a service.
>>>>>>>>>>>>>>>> d. There is a lot of extra metalogical information
>>>>>>>>>>>>>>>> about
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> services that
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> make it possible for third parties to
>>>>>>>>>>>>>>>
>>>>> develop partners
>>>>>
>>>>>>>>>>>>> for services.
>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> I, for one, would prefer a strongly anglo-saxon
>>>>>>>>>>>>>>>
>>>>>>>>>>> phrasing of the
>>>>>>>>>>>
>>>>>>>>>>>>>>>> definition of service that speaks to these points.
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Frank
>>>>>>>>>>>>>>>> ti
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> -- 
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>
>>>>> --------------------------------------------------------------
>>>>>
>>>>>>>>>>>>>>> -------------------
>>>>>>>>>>>>>>>    /   Ken
>>>>>>>>>>>>>>> Laskey
>>>>>>>>>>>>>>>         \
>>>>>>>>>>>>>>>   |    MITRE Corporation, M/S H305    phone:
>>>>>>>>>>>>>>
>>>>>>>>>>> 703-983-7934   |
>>>>>>>>>>>
>>>>>>>>>>>>>>>   |    7515 Colshire Drive                    fax:
>>>>>>>>>>>>>>> 703-983-1379   |
>>>>>>>>>>>>>>>    \   McLean VA 22102-7508
>>>>>>>>>>>>>>>            /
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>
>>>>> --------------------------------------------------------------
>>>>>
>>>>>>>>>>>>>>> --------------------
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>> -- 
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>> --------------------------------------------------------------
>>>>>>>
>>>>>>>>>>>>> -------------------
>>>>>>>>>>>>>    /   Ken
>>>>>>>>>>>>> Laskey
>>>>>>>>>>>>>         \
>>>>>>>>>>>>>   |    MITRE Corporation, M/S H305    phone:
>>>>>>>>>>>>
>>>>>>> 703-983-7934   |
>>>>>>>
>>>>>>>>>>>>>   |    7515 Colshire Drive                    fax:
>>>>>>>>>>>>> 703-983-1379   |
>>>>>>>>>>>>>    \   McLean VA 22102-7508
>>>>>>>>>>>>>            /
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>> --------------------------------------------------------------
>>>>>>>
>>>>>>>>>>>>> --------------------
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> -- 
>>>>>>>>>>>
>>>>>>>
>>>>> -------------------------------------------------------------------
>>>>>
>>>>>>>>>>> --------------
>>>>>>>>>>>    /   Ken
>>>>>>>>>>> Laskey
>>>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>>>>    \
>>>>>>>>>>>   |    MITRE Corporation, M/S H305    phone:
>>>>>>>>>>
>>>>> 703-983-7934   |
>>>>>
>>>>>>>>>>>   |    7515 Colshire Drive                    fax:
>>>>>>>>>>> 703-983-1379   |
>>>>>>>>>>>    \   McLean VA
>>>>>>>>>>> 22102-7508                                              /
>>>>>>>>>>>
>>>>>>>
>>>>> -------------------------------------------------------------------
>>>>>
>>>>>>>>>>> ---------------
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> -
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> -- 
>>>>>>>>>>
>>>>>>>
>>>>> --------------------------------------------------------------------
>>>>>
>>>>>>>>>> -------------
>>>>>>>>>>   /   Ken
>>>>>>>>>> Laskey
>>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>>>   \
>>>>>>>>>>  |    MITRE Corporation, M/S H305    phone:  703-983-7934   |
>>>>>>>>>>  |    7515 Colshire Drive                    fax:
>>>>>>>>>> 703-983-1379   |
>>>>>>>>>>   \   McLean VA
>>>>>>>>>> 22102-7508                                              /
>>>>>>>>>>
>>>>>>>
>>>>> --------------------------------------------------------------------
>>>>>
>>>>>>>>>> --------------
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>> -- 
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>> --------------------------------------------------------------------
>>>>>
>>>>>>> -- 
>>>>>>>
>>>>>>>> -----------
>>>>>>>>   /   Ken
>>>>>>>> Laskey
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>> \
>>>>>>>>  |    MITRE Corporation, M/S H305    phone:  703-983-7934   |
>>>>>>>>  |    7515 Colshire Drive                    fax:
>>>>>>>> 703-983-1379   |
>>>>>>>>   \   McLean VA
>>>>>>>> 22102-7508                                              /
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>> --------------------------------------------------------------------
>>>>>
>>>>>>> -- 
>>>>>>>
>>>>>>>> ------------
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>
>>>>> -- 
>>>>>
>>>>> --------------------------------------------------------------
>>>>> -------------------
>>>>>    /   Ken
>>>>> Laskey
>>>>>         \
>>>>>   |    MITRE Corporation, M/S H305    phone:  703-983-7934   |
>>>>>   |    7515 Colshire Drive                    fax:
>>>>> 703-983-1379   |
>>>>>    \   McLean VA 22102-7508
>>>>>            /
>>>>>
>>>>> --------------------------------------------------------------
>>>>> --------------------
>>>>>
>>>>>
>>>>>
>
> -- 
>      
> --------------------------------------------------------------------------------- 
>
>   /   Ken 
> Laskey                                                                \
>  |    MITRE Corporation, M/S H305    phone:  703-983-7934   |
>  |    7515 Colshire Drive                    fax:      703-983-1379   |
>   \   McLean VA 22102-7508                                              /
>     
> ---------------------------------------------------------------------------------- 
>
>
>


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