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Subject: Re: [soa-rm-ra] One-pager


I think that some words may be said with more care:

1) I agree with: "

So the Action Model is the set of actions a service can be asked to do in order to realize RWE.  It is potential.  Turning that potential into reality is accomplished through Joint Action between the Consumer and the Service.  The consumer is asking for the service..."

However, "The consumer " CANNOT ask "... the service to carry out the advertised action" because NO actions are advertised. The only things are advertised for an independent and self-sufficient service are a) service business functionality, b) RWE, c) communication interfaces with interface 'operations' that are the facade for one or many internal actions that the consumers should not be aware about (this actions relate to the HOW part of the service)


2) I agree with majority of the paragraph starting with "In order for Joint Action to occur..." except for two places: 
a) "Let’s look at the vocabulary example: the service description indicates the service can understand both NIEM and UCore schemas; the consumer chooses to use UCore schemas and so indicates in its messages" - the explanation of the activities on the consumer side is inaccurate - consumer may use only those messages (and related schemas) that the service specifies: if no messages contain NIEM, consumer may only suggest that the service execution can or will use NIEM but no messages with NIEM may be exchanged.
b) "If the Consumer wanted to use a schema other than NIEM or UCore, some vocabulary mediator would need to be identified and available for use in order for the EC to be successfully established" - as a explained already, it is the service that dictates messages for the service interface. I have wrote an article (http://www.infoq.com/articles/patterns-soa-business-services) where discussed what does mean ""If the Consumer wanted to use a schema other than" defined by the service. Briefly, the article's concludes that for business services either the mediator and the vocabulary mapping must be explicitly identified in the Service Contract or the consumer transforms the schema on its own, with or without the mediator, and this may not be a part of agreed (contracted) interaction.

Business service consumer cannot and will not interact with the business service if they do not understand each other initially or agreed on the translator and translation.  


3) disagree with: "there may be numerous interactions required to establish the EC" - EC exists independently and before any interactions may occur. EC is the set of policies that form the environment of communication with the service and the service execution in response to the valid communication/invocation. "establishing willingness and trust" is the process and the final state based on given EC; if an EC changes, priory established willingness may be nulled. This, however, does not preclude the consumer to use the service in the EC that is not specified by the service provider in the Service Description. Like you can drive a regular passenger car across a brook while it was announced and sold you for running on 'solid' roads. In this case, the consumer is on its own but, still, the EC is identified before and not because of any interactions take place.


4) disagree with: "action as..seems to more directly support the ecosystem context of interaction to establish EC " - actions DO NOT establish EC! A service, e.g. runs on Linux not because its future (and unknown) consumers interact with it but because the service provider has deployed it on Linux instead of Windows platform. I have a feeling that Ken tries to create a 'micro'-environment boarded by the interactions and other actions that together lead to the oint Action. This might make sense (which I still have not possessed) but it is not the EC but rather something else. 


- Michael


-----Original Message-----
From: Ken Laskey <klaskey@mitre.org>
To: 'Bashioum, Christopher D' <cbashioum@mitre.org>; soa-rm-ra@lists.oasis-open.org
Sent: Fri, Mar 11, 2011 2:47 pm
Subject: RE: [soa-rm-ra] One-pager

So the Action Model is the set of actions a service can be asked to do in order to realize RWE.  It is potential.  Turning that potential into reality is accomplished through Joint Action between the Consumer and the Service.  The consumer is asking for the service to carry out the advertised action – likely some business function –  expecting the advertised RWE.
 
In order for Joint Action to occur, the Execution Context needs to be established.   The RM defines the EC.  Much of the EC derives from information in the service description.  However, the service description may indicate alternatives, e.g. alternate restrictions on sharing private information or the set of vocabularies the service is prepared to understand.  Let’s look at the vocabulary example: the service description indicates the service can understand both NIEM and UCore schemas; the consumer chooses to use UCore schemas and so indicates in its messages.  The agreement on vocabulary is set because the EC as established allows for consistent choices among the participants and, indeed, one of those choices will be used.  If the Consumer wanted to use a schema other than NIEM or UCore, some vocabulary mediator would need to be identified and available for use in order for the EC to be successfully established.
 
It is possible that in establishing the EC, there will be resulting limitations that preclude using some of the Actions in a service’s Action Model.  This will likely affect the RWE that can be realized or the conditions under which the RWE can be realized.  For example, there can be a limit on the cost that can be incurred and so a data set will only go through one level of processing instead of a second level the service might also offer.
 
Now, there may be numerous interactions required to establish the EC.  This is most notable in the idea of establishing willingness and trust.  Our current discussion limits Joint Action to realizing actions in *an* Action Model and not every interaction that may go into establishing the EC.  Note, this does not preclude some of those interactions being done using services and that there are Joint Actions with those services.  In any case, we need to explicitly acknowledge and account – but not necessarily fully expand the social aspects in excruciating detail – for those interactions that are essential to making the ecosystem work.
 
Now action as “application of intent to achieve an effect” seems to more directly support the ecosystem context of interaction to establish EC and then engage in Joint Action than it does the idea of Action in the Action Model.  I mentioned during the last call that it seems section 3 is more what leads up to using a service and then dealing with the RWE while section 4.3 is more what happens after the joint action begins and the magic happens producing the RWE.  I’m not requesting a change in the definition but noting there is a critical need to consistently connect all uses of Action with the definition.  That is the final piece that I think will tie up discussions – I’ve been reading RA emails from 2007 and 2008 – that have gone on for years.
 
Ken
 
---------------------------------------------------------------------------
Dr. Kenneth Laskey
MITRE Corporation, M/S H305              phone: 703-983-7934
7515 Colshire Drive                                    fax:        703-983-1379
McLean VA 22102-7508
 
From: Bashioum, Christopher D [mailto:cbashioum@mitre.org]
Sent: Wednesday, March 09, 2011 1:45 PM
To: soa-rm-ra@lists.oasis-open.org
Subject: [soa-rm-ra] One-pager
 
Attached is the one-pager we talked about at today’s conference call.  For those who didn’t attend, the minutes should be posted shortly.  The purpose of this is for us  to come to agreement on these concepts and their  relationship to each other before next week’s call.
 
 


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