Re: [soa-rm] Reference Model vs. Reference Architecture (Road Map)

[Ken Laskey <klaskey@mitre.org>]

Matt,

In a previous email, I sent a definition of "framework".  How does RM 
compare to framework?  And if my framework definition works, does the 
architecture definition (which was supposed to build on the framework one) 
work too?

Ken

At 09:30 AM 5/11/2005, Matthew MacKenzie wrote:
>In my way of thinking, a reference model is actually a form of 
>architecture, although I have been straying away from portraying it in 
>that light in order to help others understand the distinction.
>
>What form of architecture?  I call it an "architectural framework".
>(for the sarcastic, you'll note that I am using two of the most overused 
>words in our field here, but I feel they work.)
>
>In my world, and architecture must be implementable and should not contain 
>too many undefined/undesigned component areas where engineers/developers 
>can make grievous mistakes.  On the other hand, an architectural framework 
>is somewhat like a UML pallette you would find in Visio -- all of the 
>concepts are represented on the pallette, and a trained practitioner knows 
>how to arrange the concepts on her canvas to draw the picture.  This 
>reference model that we are writing is effectively the training material 
>used to train practitioners.
>
>Is that clear, or have I added confusion?
>
>-Matt
>
>Chiusano Joseph wrote:
>
>><Quote>
>>I would also pick Matt's brain on this subject.  He is far more
>>knowledgeable since he lives in this world every day.
>></Quote>
>>Thanks Duane - that all makes sense. Matt, I for one would be interested 
>>in hearing anything you'd like to add please.
>>
>>Joe
>>
>>
>>Joseph Chiusano
>>
>>Booz Allen Hamilton
>>
>>Visit us online@ http://www.boozallen.com 
>><https://webmail.bah.com/exchweb/bin/redir.asp?URL=http://www.boozallen.com/>
>>
>>
>>------------------------------------------------------------------------
>>*From:* Duane Nickull [mailto:dnickull@adobe.com]
>>*Sent:* Tue 5/10/2005 8:35 PM
>>*Cc:* soa-rm@lists.oasis-open.org
>>*Subject:* Re: [soa-rm] Reference Model vs. Reference Architecture (Road Map)
>>
>>Joseph:
>>
>>I am going to take a try at this. Please forgive this next sentence:
>>
>>"A reference model is a model while a reference architecture is an
>>architecture. "
>>
>>Okay - so what does that really mean (other that I couldn't find
>>appropriate words)?  Not an easy question to answer.
>>
>>There are multiple differences you can state such as "One is
>>implement-able, the other is not".  A reference architecture does tend
>>to be more generic than most use cases would require and would still
>>need to be specialized further for a particular set of requirements.
>>
>>Reference architecture is sort of a proof of concept. Individual
>>requirements and implementations  may vary, but with the
>>data and guidelines from such reference implementations the system
>>designer can make more informed decisions.  A reference architecture
>>also may force you to consider things the RM does not delve into.  The
>>RM for building a house may have a notion of a bathroom and also a
>>kitchen.  The reference model states you have to have one instance of
>>each to fulfill the functional requirements of providing a habitat for a
>>human being, but does not show a level of detail of how you could build
>>a house having both.
>>
>>The reference architecture for a house would delve into how plumbing
>>gets from the source/target to both the bathroom and the kitchen, as
>>well as a documented layout that shows how they are connected and what
>>other common touchpoints and infrastructure they share.  It is a more
>>specific design that can also be further specialized.  It forces someone
>>architecting another house to consider the same question and perhaps
>>even shows them a solution paradigm (example - hide the pipes in the
>>wall).  This also hints at ways of implementing things that are
>>optimized (hiding pipes in the wall is better than running them outside
>>the house in climates where they may freeze).
>>
>>The Reference Architecture for this alleged house can also be modified
>>for someone who owns property that is on a 10 degree slope or is not
>>connected to a city water and sewage system (let's not get into those
>>details).  It may also further optimize the house's orientation to
>>optimize it for natural sunlight and views via windows.
>>
>>The order of abstraction is as follows:
>>
>>1. Meta models and meta conventions(ADL's and notions such as patterns
>>of pipes and filters, stacks, etc.)
>>2. Reference Models
>>3. Reference Architectures
>>4. Specific Architectures.
>>
>>There is of course, not 100% consensus on this subject and even
>>something as simple as a definition of architecture itself has proven to
>>be very difficult.
>>
>>I would also pick Matt's brain on this subject.  He is far more
>>knowledgeable since he lives in this world every day.
>>
>>Duane
>>Duane
>>
>>
>>Chiusano Joseph wrote:
>>
>> > I think it is very important that at some point we include in our spec
>> > the necessary guidance for users of our spec to move from our
>> > reference model to a reference architecture, and perhaps beyond.
>> > > I have seen so many cases in which the terms "reference model" and
>> > "reference architecture" have been used interchangeably (and sometimes
>> > in the same resource!) that I am no longer crystal clear on the
>> > similarities/differences between the 2. I know that there has been
>> > preliminary discussion that reference model != reference architecture.
>> > > Can someone please provide a clear distinction between the 2, and how
>> > we envision our RM "flowing" into an RA?
>> > > Thanks,
>> > Joe
>> > > Joseph Chiusano
>> > Booz Allen Hamilton
>> > Visit us online@ http://www.boozallen.com <http://www.boozallen.com/>
>> >
>>
>>--
>>***********
>>Senior Standards Strategist - Adobe Systems, Inc. - http://www.adobe.com
>>Chair - OASIS Service Oriented Architecture Reference Model Technical 
>>Committee -
>>http://www.oasis-open.org/committees/tc_home.php?wg_abbrev=soa-rm
>>Vice Chair - UN/CEFACT Bureau Plenary - http://www.unece.org/cefact/
>>Adobe Enterprise Developer Resources  - 
>>http://www.adobe.com/enterprise/developer/main.html
>>***********
>

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   /   Ken 
Laskey                                                                \
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