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

[Ken Laskey <klaskey@mitre.org>]

P.S. The rest is good fodder to chew on. Thanks.

At 08:35 PM 5/10/2005, Duane Nickull wrote:
>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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