In the example from Michael, where he considered one solution to be more service oriented than another, the business intent was the same. As far as I'm able to interpret his exemple, the difference was in the choosen technology and the implementation of the technology.

Actually, after all this years with service orientation, I think we have learned a lot, but we still can't unambiguously define a service and tell a service oriented solution apart from a non-service oriented solution. The grey zone is as big as ever.

On the positive side I think SOA has helped many people in IT too think more about the business side of solutions to problems that involves IT. I also think SOA and the principles of service orientation has raised many important and worthwhile questions and discussions during the years, but I find it ironic that it still is very hard to unambigously tell if a solution is service oriented or not.

// Dennis Djenfer


Steve Jones wrote:


Technology v Business intent. Integration solutions are purely about the connection of pieces of technology that may at a 2nd remove deliver a business value. A service is directly about the delivery of the business value.

In other words (and I think the SOA-RM does this brilliantly) its the difference between technology infrastructure (the Execution Context in the SOA-RM) and the actual capabilities and service. Integration solutions place the technology at the heart and then plug things together, SOA places the capabilities and services at the heart and relegates the internals to just plumbing.

Steve


2009/12/29 Dennis Djenfer <[email protected] <mailto:[email protected]>>

    Ok, so what is the behavior of your solution that makes it qualify
    as service oriented and not as a pure integration solution?



    // Dennis Djenfer


    Michael Poulin wrote:
    Qualification 'into service', IMO, is not in the interface but in
    behavior of the entity.
    - Michael

    ------------------------------------------------------------------------
    *From:* Dennis Djenfer <[email protected]> <mailto:[email protected]>
    *To:* [email protected]
    <mailto:[email protected]>
    *Sent:* Sun, December 27, 2009 5:11:11 PM
    *Subject:* Re: [service-orientated-architecture] Descriptions vs
    Contracts

    I wonder if that is enough to qualify as a service oriented
    solution. With that kind of reasoning a Web Service slapped on a
    database because an application needed the data would be service
    oriented.

    // Dennis Djenfer


    Michael Poulin wrote:

    Service orientation in my solution is in Documentum service
    offered a service (via JMS) and all interested (the ATG Dynamo
    servers) were able to use it.  In the contrast, the Documentum's
    solution was based on blind push of information to pre-defined
    IP address with no mechanism for the consumers to change them at
    wish (but only through the negotiation with and reconfiguration
    of the Documentum server). I think that my solution was
    service-oriented while the Documentum's one was much more
    traditional P2P integration. This is the about "the right way of
    thinking" or freedom for consumers (specific to SO) rather than
    technology comparison.

    - Michael

    ------------------------------------------------------------------------
    *From:* Dennis Djenfer <d...@algonet. se> <mailto:[email protected]>
    *To:* service-orientated- architecture@ yahoogroups. com
    <mailto:[email protected]>
    *Sent:* Sat, December 26, 2009 10:23:30 PM
    *Subject:* Re: [service-orientated -architecture] Descriptions
    vs Contracts

    I don't get why your solution is service oriented. All I can
    read from your exemple is two kind of solutions for an
    integration problem. They have different technical solutions and
    quality attributes, but I don't get why one of them is service
    oriented.

    // Dennis Djenfer


    Michael Poulin wrote:

    I think, Sun Tzu  in his  /T
    
<http://www.1000ventures.com/business_guide/crosscuttings/cultures_sun_tzu_the_art_of_war.html>he
    Art of War
    
<http://www.1000ventures.com/business_guide/crosscuttings/cultures_sun_tzu_the_art_of_war.html>
 / has
    given us the receipt for SOA implementation for downtime saying
    "Nothing is as important as having the right way of thinking."

    SO is about SO thinking; SO needs technologies and expensive
    systems at the very last, if ever, moment. SO is not in
    technologies like BPEL and others. You can build service
    orientation into regular code if you think first about it.

    For example, several years ago I had a problem to solve: our
    Documentum server prepared Web content, which had to be used by
    the Application/ Web Servers (ATG Dynamo that time) to publish
    on the Web, but did not notify ATG Dynamo when the content was
    ready. Our Business publisher authored the content but could
    not manage the publishing time. In my SO Solution, I
    placed Documentum' s meta-file about prepared content into
    MOM/Topic and made all ATG Dynamo servers to subscribe to the
    Topic announcements. The ATG Dynamo servers used to be
    re-booted nightly but they were able to get all missed
    information and the new one due to the durable subscription to
    the MOM Topic. Where ATG Dynamo servers were shut down and
    where they (or their replacements) came up on-line (i.e. their
    IP address) did not matter to the solution. [When Documentum
    learnt this solution from us, they provided a free integration
    Documentum-ATG Dynamo via Web channel. In their
    solution, Documentum not only updated the data-store with the
    prepared content but also sentthe  appropriate Web 'requests'
    to the registered ATG Dynamo servers. It looked fine except for
    the cases when ATG Dynamo servers lost all information when
    being down and had to get on-line with exactly the same IP
    address they registered with the Documentum server before. This
    was pure integration solution while I can consider my solution
    was much more service oriented.]

    - Michael

    ------------------------------------------------------------------------
    *From:* Hitoshi Ozawa <htshoz...@gmail. com>
    <mailto:[email protected]>
    *To:* service-orientated- architecture@ yahoogroups. com
    <mailto:[email protected]>
    *Sent:* Fri, December 25, 2009 10:56:29 PM
    *Subject:* Re: [service-orientated -architecture] Descriptions
    vs Contracts

I think you've hit the major difference we're having. I'm in an
    actual project and tailoring my service so they can actually be
    implemented with the current available technology, development
    members, and other constraints. Also, with the economic slow
    down, it is also necessary to reduce cost.
    There was a mention of BPEL in the other thread, and I think
    the basic technology is interesting, but the current situation
    requires too knowledge of too many specifications that it
    almost impossible to educate development members to complete a
    project in time. Of course, in a small project, I can just do
    it myself but in a large project, that's impossible.
SOA is dying not because the theory behind it is bad, but that
    what most people are preaching can not currently be implemented
    in a project. The tight economy is also sifting the emphasis
    from "to be" more toward  "can be".

    Anne's cartoon showed a "SOA dinosaur", but IMHO the dinosaur
    really isn't the concept of SOA itself, it more of us who's not
    adjusting to the current economic market.
Happy Holidays,
    H.Ozawa
2009/12/25 Steve Jones <jones.steveg@ gmail.com
    <mailto:[email protected]>>

        I'm designing them in this way but unfortunately in
        implementation there isn't the technology to support this
        stuff.  WS-Contract or WS-SLA never happened and there
        isn't anywhere near the formalism required.


        Steve


        2009/12/23 Hitoshi Ozawa <htshoz...@gmail. com
        <mailto:[email protected]>>

So Steve, you're designing all your services these way.

            H.Ozawa
            2009/12/23 Steve Jones <jones.steveg@ gmail.com
            <mailto:[email protected]>>

                I can't see why not, although I'd reword it to be


                In order to ship the carton a valid set of legal
                constraints, written in French, must be agreed.


                Take Air Traffic Control, there are two official
                global languages for ATC there is English (used in
                99% of the world) and there is French (guess where
                that is used) but they are both official languages
                at the service description level.   Now some people
                can constrain their description to say "we only
                accept English" but this is still at the service
                description level as an individual contract (with a
                plane) has not yet been entered into.

                Steve


                2009/12/22 Hitoshi Ozawa <htshoz...@gmail. com
                <mailto:[email protected]>>

We're talking about service description. Is it
                    alright to have "ship the carton with a valid
                    set of legal constraints in French"?
H.Ozawa

                    2009/12/23 Steve Jones <jones.steveg@ gmail.com
                    <mailto:[email protected]>>

                        I can't see why a contract of send invoice
                        via SOAP would be a problem with the
                        description being "send invoice", why would
                        it be a problem?


                        I think we are in danger of disappearing
                        into semantic holes.  I could argue that if
                        the objective (service description) was to
                        woo a lady then the choice of the language
                        (service contract) could be either English
                        or French.  In French we could take the
                        Cyrano de Bergerac approach while in
                        English we could fall back on the Bard of
                        Avon.  Here the language is the piece that
                        seals the deal and is linked to the
                        specific consumer of the service, in other
                        words the language chosen (the contract) is
                        linked to the specific engagement between
                        the producer and consumer.

                        Steve



                        2009/12/22 Hitoshi Ozawa <htshoz...@gmail.
                        com <mailto:[email protected]>>

Hi Steve,
                            So are you implying "send invoice using
                            SOAP"  is alright?
                            If you are, I sure would like to see
                            the system with such a design. :-)
French and English are languages people
                            use to rely concepts. British law is a
                            concept. Concepts described in the
                            British law does not (should not)
                            change whether it's written in English
                            or in French.
H.Ozawa
                            2009/12/21 Steve Jones <jones.steveg@
                            gmail.com <mailto:[email protected]>>

                                I actually think that French and
                                English is fine.  It is like having
                                a shipping contract, there are a
                                huge number of different legal
                                jurisdictions that you could
                                potentially use to ship the product
                                from A to B (the description) but
                                when you formalise the contract you
                                pick a single legal country as your
                                escalation point.


                                So in other words the description
                                of A to B just says "ship the
                                carton with a valid set of legal
                                constraints" while the contract
                                says "ship the carton with British
                                Law as the legal framework"

                                Steve


                                2009/12/19 Hitoshi Ozawa
                                <htshoz...@gmail. com
                                <mailto:[email protected]>>

Andrew,
                                    I think you're beginning to
                                    understand the concept,
                                    but your example is missing the
                                    point.
                                    Your analogy with French and
                                    English is inappropriate unless
                                    you're thinking of a
                                    translation service.
Service description describes
                                    the semantic capabilities of
                                    the service while service
                                    contract describes the set of
                                    rules  used in an instance of
an interaction. H.Ozawa
                                    2009/12/18 Andrew Herbst
                                    <herbst_andrew@ yahoo.com
                                    <mailto:[email protected]>>

Greetings: Another question from an
                                        SOA neophyte.  Thanks for
                                        responding to my earlier
                                        questions.
So, roughly speaking, a
                                        service description is like
                                        me announcing to the
                                        world:  “I can interact in
                                        French *or* in English”,
                                        whereas, a service contract
                                        is like me agreeing to
                                        speak French with a
                                        specific other person in
                                        the context of some very
                                        specific interaction.
I realize this is a very
                                        basic question, and it may
                                        well not really be the aim
                                        of this group to deal with
                                        such basic things.  I will
                                        therefore take no offence
                                        if no one addresses this.
Thanks, Andrew Herbst
















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