Re: [soa-rm] another possible SOA diagram (revised)

[Ken Laskey <klaskey@mitre.org>]

Again, this came out of the metadata analysis for a DoD SOA.  I wasn't 
intending to make this WS-specific but that could easily leak in.  Anyway, 
whether Web services or not, you ask a data resource a question and it 
gives you an answer; you ask a processing resource to do something and it 
tells you what it did.  Many services will make use of both types of 
resources when fulfilling a function.  (And how complicated does the 
function have to be to consider the service as an intermediary 
resource?)  The distinction was useful in the metadata analysis context and 
we can see if it provides value here.

Ken

At 11:41 AM 5/24/2005, you wrote:
>I see v. little difference in the distinction between data resource
>and process resource.
>
>I think that your data resource concept -- which I assume is inspired
>by web servers -- can be considered to be a special case of process
>resource -- which I also assume is inspired by Web services :). Web
>servers are a kind of processing entity that might be paralleled with
>*transducers* -- mapping signals in one domain to signals in another
>domain.
>
>
>On May 23, 2005, at 2:26 PM, Ken Laskey wrote:
>
>>Whatever is behind the service interface and provides either data
>>and/or processing is a resource.  As intended for the 07 draft and
>>unfortunately half finished in the version I actually sent to Matt:
>>
>>Consider, for example, the descriptive elements that may apply for
>>a data resource vs. a processing resource.  Here, we will assume
>>the resources to be distinguished as follows:
>>·         A data resource is a source of content that accepts a
>>request and returns a value or set of values in response.  The
>>return can be an entity (such as a particular schema), an attribute
>>of an entity (such as when the schema was last modified), or any
>>numerical or textual value or set of values. The content can be
>>static objects stored in some repository or dynamically generated
>>through the use of a processing resource.
>>·         A processing resource is one that accepts a task and
>>return a status indicating the extent to which the task was
>>completed and information on how the state of entities changed as a
>>result of the processing.  One or more processing resources may be
>>invoked as part of a process of submitting a query and being
>>returned a response.  From the standpoint of a user (either human
>>or machine), it is unimportant what combination of data and
>>processing resources are invoked as long as the request is satisfied.
>>
>>Both types of resources are likely to have descriptive items such
>>as a name, a textual description, and possibly a set of descriptors/ 
>>keywords with a pointer to the vocabulary definition from which the
>>descriptors/keywords are taken.  Both resources may also identify
>>responsible parties, including who is responsible for operations,
>>who is responsible for design, who is responsible for
>>implementation.  However, it may be appropriate for a data resource
>>to publish its update cycle so a consumer can decide if the
>>resource is current enough for its needs.  The processing resource,
>>on the other hand, might publish its current version number (with a
>>reference giving a context for the version numbering semantics) and
>>a development status (with a similar defining reference).
>>Additional constraints and policies could be connected with these
>>descriptive elements.  For example, if a particular processing
>>resource has a beta status, access may only be granted to certified
>>beta testers.
>>
>>Ken
>>
>>At 11:52 AM 5/23/2005, Chiusano Joseph wrote:
>>
>>>Ken,
>>>
>>>Given an example of a purchase order service (a service that accepts
>>>purchase orders and generates invoices, enables a user to check
>>>status
>>>of purchase orders, add line items to previously generated purchase
>>>orders, etc.):
>>>
>>>What would be an example of a resource?
>>>
>>>Thanks,
>>>Joe
>>>
>>>Joseph Chiusano
>>>Booz Allen Hamilton
>>>Visit us online@ http://www.boozallen.com
>>>
>>>
>>> > -----Original Message-----
>>> > From: Christopher Bashioum [mailto:cbashioum@mitre.org]
>>> > Sent: Monday, May 23, 2005 11:50 AM
>>> > To: 'Ken Laskey'
>>> > Cc: 'SOA-RM'
>>> > Subject: RE: [soa-rm] another possible SOA diagram (revised)
>>> >
>>> > Ken,
>>> >
>>> > I would have expected the service interface and the resource
>>> > to be smaller boxes inside of the service box.  It looks
>>> > funny to have the service off to the left, and the service
>>> > interface and resource on top.
>>> >
>>> > -----Original Message-----
>>> > From: Ken Laskey [mailto:klaskey@mitre.org]
>>> > Sent: Monday, May 23, 2005 11:13 AM
>>> > To: Christopher Bashioum
>>> > Cc: 'SOA-RM'
>>> > Subject: Re: [soa-rm] another possible SOA diagram (revised)
>>> >
>>> > The resource is the implementation that in many cases was
>>> > created to satisfy needs outside the SOA and only becomes
>>> > part of a SOA in the same way that any software package
>>> > becomes part of your computer.
>>> > Opacity says you know there is a resource but the only thing
>>> > you know about it is what is exposed through the service
>>>description.
>>> >
>>> > Attached is a very quick attempt to include in Duane's last
>>>diagram.
>>> >
>>> > Ken
>>> >
>>> >
>>> >
>>> >
>>> >
>>
>>--
>>
>>---------------------------------------------------------------------- 
>>-----------
>>   /   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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