Fwd: [soa-rm-ra] Need some clarification on actions, message exchange, & operations

[Francis McCabe <frankmccabe@mac.com>]

Begin forwarded message:

> From: Francis McCabe <frankmccabe@mac.com>
> Date: February 5, 2007 4:25:50 PM PST
> To: "Jeffrey A. Estefan" <jeffrey.a.estefan@jpl.nasa.gov>
> Subject: Re: [soa-rm-ra] Need some clarification on actions,  
> message exchange, & operations
>
> This is how I see things:
>
> Action: the application of intent by an agent to achieve an effect.
>
> I think that one thing that might be important here is joint action:
>
> Joint Action: the application of intent by two or more participants  
> to achieve an effect.
>
> (Paraphrased from Herbert Clark)
>
> The Action model is a characterization of the joint actions that a  
> service can participate in.
>
> Operations: the sequence of (private) actions a service must  
> perform in order to validly participate in a given joint action.
>
>
> Message exchange: the means by which a joint action is coordinated  
> by the participants
>
> Execution context: the environment in which joint actions occur.
>
> Hope that this helps!
>
> Frank
>
> On Feb 2, 2007, at 4:26 PM, Jeffrey A. Estefan wrote:
>
>> Frank and Team,
>>
>> We need to resolve some of the ambiguities surrounding the  
>> following concepts and their relationships in the context of  
>> service interaction:
>>
>> 1. Actions
>> 2. Action model
>> 3. Operations
>> 4. Message exchange
>> 5. Real world effect
>> 6. Execution context
>>
>> Omitting item 6 for the moment, here's what I've captured during  
>> my note taking from the various telecons and discussion threads.
>>
>> * An action is expressed or defined in terms of message exchange  
>> between participants. In other words, exchange of a message counts  
>> as performing an action.
>> * The action model (an element of a service description’s behavior  
>> model) describes the set of actions required to result in a real  
>> world effect.
>>
>> * The combination of the message exchange and the message content  
>> denote the action.
>>
>> * The action results in an operation being performed.
>>
>> * The result of an action can result in an operation on the  
>> service and the result of an operation would be the real world  
>> effect.   Consequently, the action results in an operation being  
>> performed
>>
>> So, one concept that needs to be clarified based on the attached  
>> UML diagram is operation (see fourth bullet above).  In other  
>> words, does operation exist in between action and real world  
>> result?  And what about the content of the message as stated in  
>> the third bullet above.
>>
>> Obviously, there are some ambiguities here and I'd appreciate any  
>> help in the clarification so we can press ahead with the write- 
>> up.  In the meantime, I will describe and model a few common MEPs  
>> and include them in the write-up as well as the common interaction  
>> model that depicts the role of the service participants, agents,  
>> and intermediaries (PEP, PDP).
>>
>> Cheers...
>>
>>  - Jeff E.
>>
>> <messages.png>
>