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Subject: Re: [soa-rm-ra] reaching closure on Action


In Cayenne ...

On Jun 10, 2008, at 7:31 PM, Ken Laskey wrote:

In orange...

On Jun 10, 2008, at 8:41 PM, Francis McCabe wrote:

In Magenta...
On Jun 10, 2008, at 2:52 PM, Ken Laskey wrote:

Then my responses must be in Lime.
Ken

On Jun 10, 2008, at 4:37 PM, Francis McCabe wrote:

My responses in Strawberry...
Frank


On Jun 10, 2008, at 11:21 AM, Ken Laskey wrote:

OK, let's see if we're getting somewhere?

Ken

P.S. This has to be resolved before we run out of distinct colors.

On Jun 10, 2008, at 1:54 PM, Francis McCabe wrote:


On Jun 10, 2008, at 10:02 AM, Ken Laskey wrote:

I changed the color of a few lines below to red because these start getting to my questions.

Now while I'd still like you (or someone else) to respond to the questions below (timestamp 6:59 AM) as stated, I can infer from your response that anything done by a speaker with the purpose of applying intent is Action on the part of the speaker, whether or not it is effective.  At a minimum, it requires a listener to have any chance to be effective.  However, from the context of the speaker, it is an action either way.


Yes.

If a listener hears what the speaker says, we have joint action, in the form of CA.


Yes.


 This still doesn't tell me how CA does something (i.e. the initiating activity) to get something done, i.e the RWE.

Also, what is the intent applied by the listener?  Is it simply to hear what a speaker says?  At a minimum, it should probably also be interpreting the message and deciding if it is part of the Action Model of the service it is listening for.

Yes.

However, I think that this is where the counts-as relation comes in to play. For the listener to understand that a CA is supposed to result in a service action, the listener must apply that relation. In effect, there is a shift going on from communication actions to service actions.


You just can't say counts-as and sweep it under the rug.


How specific do we need to get? I do not feel a need to sweep stuff under the carpet.


As I think Rex noted, we are changing modes.  The speaker successfully sent the message because the listener received and was able to accurately interpret it.  I believe this requires more than would be required of a traditional listener.  Is this correct?

Not really. But there is an unknowable gap here: there is no way that an external observer can determine if a listener has understood something accurately. We should not require this.


In the nominally successful (even less than ideal) situation, this is what happens.  For the current discussion, the unknowable gap should also be unmentionable.

I agree. That implies that the only semantics that we can be concerned about is so-called public semantics. That in turn implies that anything that goes on as a result of a service being acted on is either in the public description of the RWE or does not happen -- from the perspective of an external observer.

So, any discussion of follow on activities within a service is out of bounds. That pushes the focus back to the Service Action.




The CA phase is done and the service action phase begins.  The message is one recognized by the service Action Model and the listener or the someone/something for which listening is being done will then initiate activity in response to the interpretation of receiving the message and processing its payload.  

I have heartburn with Rex's view of events. This phase model may be helpful for many people; but this is a realizing SOA concept not a EcoSystem concept. For the EcoSystem view, the counts-as relation seems more appropriate.


At this point, I don't care which view we will have which pieces of the discussion, but I am concerned that we know what we mean.  If I'm playing cards and claim the remaining tricks, this counts-as playing out the hand and winning the tricks individually.  If I leave a message with my daughter to give to my wife, this does not count-as giving the message to my wife.  I feel the same kind of disconnect with the CA/SA gap.  We need to say something about bridging the gap.

One of the key assumptions of the public semantics is that the medium of communication 'works'. If the medium is not reliable, then that must be accounted for.

As far as the CA/SA gap, what counts-as is doing is connecting two separate systems of 'logic'. I can see rules that look like:

<msg><service name="yourService"><action name="doSomething"><parameter>With This</parameter></action>... counts-as yourService.doSomething(With This)

(Fictitious example obviously).



The activity results in RWE which are specific things that constitute providing the described business functionality.  There may be a Process Model that defines intermediate public steps.  Each of these will require a successful CA that leads to initiating required action and further RWE, and this continue until the processing is complete.

absolutely.


You may cover it below, but I still ask whether the details of CA are needed in the general discussion or only when the specifics of consumer and service agents are required.



Let me try to answer your questions directly:


- If a speaker does something that s/he believe is an application of intent but it fails, what has happened? 

Not much has happened; depending on where in the chain of reasoning the failure occurred.

 Does it matter if the application was insufficient and would never work or if this instance of the application failed but in general it would work?  

I suspect that you cannot distinguish these cases in general.

I think something auditing (attempted) interactions could identify where and how consistently it failed.

If you succeed, do not forget to patent it :)

I was thinking more of a Nobel Prize in Services.



Does it matter if there was no listener or if the listener, say as a defensive maneuver, didn't respond?  

Without an active listener, there is no CA.


Does it matter if there is misunderstanding of the message or the RWE and what results is not in line with the original intent?

It seems to me that there are several questions here:

a. If the listener knows that he has not understood, then he can detect a failure at the level of the CA.

b. If the listener believes that he has understood, but in fact his understanding is incorrect, then all bets are off. A higher-level observer might be able to determine that a misunderstanding has occurred -- similar in a way to monitoring obligation policies.

c. If the listener has understood appropriately, but the RWE is not what the speaker intended, then the law of unintended consequences seems to apply :) My guess is that this is not even computable in the general case.


For the case where we have an instance failure, we'll have a challenge explaining how someone doing the exact same thing is sometimes applying intent and sometimes not.

Applying intent is independent of the result. 

Glad this is resolved!



- If the application of intent
  (1) the creation and sending of the message, or

For the speaker, there are three understandings of action that need to be understood:

a. He intends to send the message
b. He intends to play his role in the joint action of communication
c. He intends to play his role in the action conveyed in the message.

what action is conveyed by the message?

I think that to properly resolve this would imply going into speech act theory more deeply. One approach is to standardize messages a la FIPA/KQML into performatives and propositional content. I for one would not be averse to this, but I think that that may not fly very well with the larger industry :)

No, we need a one line answer, not a formal representation.  From any of our variants of action, what action is conveyed by the message?  From my response above, I would say, "initiate activity."

No. The action conveyed is presumably one of the actions in the action model. A listener's response may be to initiate some activity, but the CA conveys an action from the Action model.


Let me be stronger: The action conveyed *is* one of the actions in the action model.  That is the CA.  We still need to bridge to the SA.

As soon as you say "the action conveyed in the message is one of the actions in the action model" you *have* bridged the gap. The action model is a service model, not a communications model.







  (2) the sending (speaker) and receiving (listener) of the message, or

When both speaker and listener play their roles, they both intend to take part in the join action of communication

  (3) the sending (speaker), receiving (listener), and activity initiation in response (who wanted listening to occur)?

As above, except that now we engage the counts-as relation to shift the CA to the service action.

We have to say something more concrete than counts-as.  This sounds like my daughter trying to get homework credit because at some point she put the assignment in her backpack.

Well, we do state somewhere that messages denote actions and events. Is that sufficient? Almost certainly not in practice. Do we need to do more? I do not know.


Consider the more I wrote above.


Again, a service action is also a joint action (in my opinion).

How does this relate to Action in the service's Action Model?

I think that the action model characterizes the set of available actions against the service. They are all joint actions in that other participants are (normally) performing those actions. Something like the actual performance of a Service Action is a Joint Action?


So the actual performance of a service action (i.e., the receiving and interpreting of the incoming message and initiating activity in response) is a Joint Action but the Action as described in the Action Model is a potential.  

I think that that is accurate.

Whether I would say singular depends on our definition of singular.  But if not singular, we still need a compelling example (which seems to have slipped away) of when is a SOA-relevant action not a joint action.

I think that the logic of our discussion suggests that all actions as conveyed by message interaction are joint.


So I'm back to having lost the bubble on what is a SOA-relevant single action.  Or are all actions joint?

This would not cause me heartburn.





The proper role for the listener (service) is to respond as though the service action had been intended.

Then I get back to my question of whether we really need all the redirection through the listener.  The consumer invokes/directs an action against a service by sending it a message and the service responds with, in the ideal case, the stated RWE or, in a fault case, some explanation of what went wrong.  The joint action is between the consumer and the service, possibly the service provider.

The code that is executed by a listener is going to be pretty similar however you architect it. one benefit of the CA/SA distinction is that it helps to clarify why the different parts of that code belong in different places: service action code vs MEP code.


Does this get too concrete?  If there is an overall contextual point to be made, then we should make it and make it clearly.  If not, we have enough other things to write about.

I was giving an example... 





There is still the corner case where the listener is listening, understands that a service action is intended, but is not willing to participate in the service action. This is what we meant in the RM by willingness.


This is just one of the possible responses that I allude to above, and I don't think it is really a special case.

I agree. It is a corner case but not an impossible case. What is going on there is that the CA is *successful* but the SA is not.


In life, a response is sometimes what you expect and sometimes not.  Except for extreme cases, you just process what happens and carry on.  I tell my daughter to find another copy of her homework assignment because it's really irrelevant if she didn't put it in her backpack, she put it in but it fell out, or there really is a miniature black hole that sucks it to another universe.  The RWE of the ice cream will not happen until the homework is done.

She is lucky that ice cream is an option ... :)


Getting late and I'm wandering.




Whichever one (or combination) you pick, please relate it back to the Action Model.








 Or is the service the listener?

Again, I was careful with the questions below because answering those will get immediately to my pain points, and I hope those of others too.

Ken


On Jun 10, 2008, at 12:04 PM, Francis McCabe wrote:

I think that we need to be clear about the distinction between action and effect.

So, whether or not it is effective, action is the application of intent .... etc.

The effect of performing an action is captured in the RWE.

So, if a speaker says something, and noone was listening then:

1. There was no communicative action
2. The RWE was minimal (it is never completely null, but presumably no answer counts as much less of an effect than intended).

For there to be a CA, there must have been some level of engagement, and hence some level of RWE. But it is still possible for that to be less than expected.

It is possible for a speaker to intend to engage in a CA; without it happening. Both parties must intend for it to happen -- hence the joint part of the joint action.

Frank

P.S. To Rex: this discussion is clearly important for our own understanding. It is a separate question as to how much this affects the spec.


On Jun 10, 2008, at 6:59 AM, Ken Laskey wrote:

I don't dispute the idea that for there to be communications and *effective* application of intent, there needs to be a speaker and a listener and they have to actively participate and understand each other.  The question is how this relates to the thing(s) we call Action.

Let me try to capture this in a couple questions:

- If a speaker does something that s/he believe is an application of intent but it fails, what has happened?  Does it matter if the application was insufficient and would never work or if this instance of the application failed but in general it would work?  Does it matter if there was no listener or if the listener, say as a defensive maneuver, didn't respond?  Does it matter if there is misunderstanding of the message or the RWE and what results is not in line with the original intent?
For the case where we have an instance failure, we'll have a challenge explaining how someone doing the exact same thing is sometimes applying intent and sometimes not.

- If the application of intent
  (1) the creation and sending of the message, or
  (2) the sending (speaker) and receiving (listener) of the message, or
  (3) the sending (speaker), receiving (listener), and activity initiation in response (who wanted listening to occur)?
Whichever one (or combination) you pick, please relate it back to the Action Model.

Ken

On Jun 10, 2008, at 9:03 AM, Francis McCabe wrote:

I mis-stated something last night:


2. As far as a speaker providing intent without a listener that is true. But the CA is not *effective* without a listener.

This is true; but on reflection, it is beside the point.

The critical point is that there can be no act of communication -- no application of intent -- unless there is both a listener and speaker. So, if I talk to an empty room, I am talking but not communicating.

On the other hand, even when we are communicating, it does not mean that it is successful communication: I can listen to you, and still fail to understand/act what you are saying.

Frank



On Jun 9, 2008, at 7:43 PM, Laskey, Ken wrote:

I agree that the speaker and listener are actively involved in communication.  Our question is what is their involvement.  When does listening include the activities that the speaker wishes to follow from not only the listening but hearing and understanding.

In the Action Model, the service identifies the messages it understands when it is a listener.  It does not guarantee it will do anything for any other messages.  It does not need a speaker present to still understand those messages.

So the disconnects are:
1. There seems to need more than a speaker and a listener to have a useful service interaction, i.e. the listener has to commit to initiated activity.  Our discussion doesn't include that.
2. The speaker can apply intent without the listener receiving the message or responding.  There is action on the part of the speaker but no interaction.
3. Action, or at least potential action, exists on the part of the listener without any speaker.  There is potential for interaction, there are prescribed steps in interaction, but there is no interaction until until there is a speaker, an exchange of information, and an understanding of that exchange.

Ken

P.S. We've been offlist for a while.


-----Original Message-----
From: Francis McCabe [mailto:frankmccabe@mac.com]
Sent: Mon 6/9/2008 9:55 PM
To: Laskey, Ken
Subject: Re: [soa-rm-ra] reaching closure on Action

Ken
There is a book that I recommend that you read. It is called "Using
Language" by Herbert Clark. It is pretty informal but gives an
excellent account of the concepts involved in human communication, and
by extension computer communication.

Essentially, the bottom line is that both speaker and listener are
actively involved, and that the communication has not happened without
both participating. And he also addresses (not in the same language)
the counts-as relationship.

As for denial of service, etc., I agree that willingness is an
essential part of what is going on. hence the active role of both
parties!

Frank



On Jun 9, 2008, at 6:08 PM, Laskey, Ken wrote:

> Arghh!!!
>
> In email , I'll buy that the speaker creates and sends the message,
> but the listener only becomes aware that the message exists.  The
> speaker assumes whatever is listening will initiate the activity of
> opening and reading.  As with a denial of service attack where it is
> appropriate to withhold/withdraw willingness, whatever has the
> listener may not process the email if they suspect embedded malware.
>
> Ken
>
>
> -----Original Message-----
> From: Francis McCabe [mailto:frankmccabe@mac.com]
> Sent: Mon 6/9/2008 7:54 PM
> To: Laskey, Ken
> Subject: Re: [soa-rm-ra] reaching closure on Action
>
> No, this does not get the join action aspect.
>
> I admit that I thought some about the Patient in a CA. I believe that
> the Patient in a CA is the medium of communication. We jointly act on
> the email medium when we communicate by email. It is a little tricky
> because there is some danger of infinite regress:
>
> I act on an email to compose it and to push it into the Internet. You
> act on the email to open it and read it. But these actions are the
> actions of Speaking and Listening respectively. The Joint CA is the
> combination of the two. In that world, we are using the Internet
> (actually SMTP) as a means of communicating and we act on it by
> sending and receiving messages (the messages become the Instruments of
> our CAs).
>
>
> On Jun 9, 2008, at 3:59 PM, Ken Laskey wrote:
>
> > Wouldn't
> >
> > CA -> Agent -> Speaker=Initiator
> > CA -> Instrument -> Message[Do ServiceActionPerformative]
> > CA -> Patient -> Listener=Service
> > CA -> Verb -> CA_Performative
> >
> > where I assume CA_Performative is pass message.  I can't see having
> > two Agents and no Patient.
> >
> >
> > For a ServiceAction SA, we get
> >
> > SA -> Agent -> Initiator
> > SA -> Instrument -> CA
> > SA -> Patient -> Service
> > SA -> Verb -> ServiceActionPerformative
> >
> > Is ServiceActionPerformative what I have called Initiating Activity?
> >
> > Ken
> >
> > On Jun 9, 2008, at 6:48 PM, Francis McCabe wrote:
> >
> >> There is nothing about intent that denies join intent. A joint
> >> action necessarily implies joint intent -- both speak and listener
> >> intend that there be a communication.
> >>
> >> And yes, the communicative action involves *both* the sender and
> >> the receiver.
> >>
> >> And no, the service action is *not* singular: it is the actor
> >> acting on the acted.
> >>
> >> If we expand the ontology of action a little bit:
> >>
> >> Action -> Agent
> >> Action -> Instrument
> >> Action -> Patient
> >> Action -> Verb
> >>
> >> where Agent is the entity performing the action, Instrument is the
> >> tool with which the action is performed, Patient is the target of
> >> the action and Verb is the action being performed.
> >>
> >> Then, for a CA, we get
> >>
> >> CA -> Agent -> [Speaker=Initiator, Listener=Service]
> >> CA -> Instrument -> Message[Do ServiceActionPerformative]
> >> CA -> Patient -> None
> >> CA -> Verb -> CA_Performative
> >>
> >> For a ServiceAction SA, we get
> >>
> >> SA -> Agent -> Initiator
> >> SA -> Instrument -> CA
> >> SA -> Patient -> Service
> >> SA -> Verb -> ServiceActionPerformative
> >>
> >> The counts-as relation has to map the two actions, probably as here
> >> by linking the Instrument of the CA to different parts of the SA,
> >> as well as some implied linking between Listener/Service etc..
> >>
> >> This is probably a whole lot more detailed than we should go into
> >> in the spec; but if *we* need to to convince ourselves, so be it :)
> >>
> >> Frank
> >>
> >> On Jun 9, 2008, at 2:24 PM, Ken Laskey wrote:
> >>
> >>> I still have the question of whether Action as the application of
> >>> intent requires a receipt of that intent.  This is back to the
> >>> singular vs. communicative nature of the Action.
> >>>
> >>> If the message is the Action, then the Action has to be both the
> >>> sending AND receiving of the message in order for it to be a
> >>> communicative action.  Intent sounds like one way; it is my
> >>> motivation and the action is my acting on that motivation, but
> >>> that is all separate from the receiver.
> >>>
> >>> The Service Action, OTOH, is singular on the side of the service/
> >>> receiver.  The service Action Model delineates what messages need
> >>> to be sent in order for certain "activities" to be carried out,
> >>> leading to certain RWE.  The Action Model exists independent of a
> >>> speaker.
> >>>
> >>> The Communicative Action CANNOT count-as the Service Action
> >>> because one requires a speaker and the other does not.
> >>>
> >>> Ken
> >>>
> >>> On Jun 9, 2008, at 1:13 PM, Francis McCabe wrote:
> >>>
> >>>> I believe that there are 4 'concepts' of action involved:
> >>>>
> >>>> 1. The abstract sense of Action. Application of intent etc.
> >>>> 2. Abstract Joint Action (which is either a subclass of Action or
> >>>> a particular use of Action; not sure of the right relationship).
> >>>> 3. Communicative Action (which is a subclass of Abstract Joint
> >>>> Action)
> >>>> 4. Service Action which is an Action against a Service (which is
> >>>> described in the Action Model and the Process Model)
> >>>>
> >>>> 3. and 4. are connected via the counts-as relationship:
> >>>>
> >>>> A valid Communicative Action counts as a Service Action
> >>>>
> >>>> At some level, all of these should be introduced and explained in
> >>>> Section 3.
> >>>>
> >>>> Frank
> >>>>
> >>>>
> >>>>
> >>>> On Jun 6, 2008, at 12:02 PM, Ken Laskey wrote:
> >>>>
> >>>>> Dear Fellow Explorers,
> >>>>>
> >>>>> We've had some very stimulating discussions over the past few
> >>>>> weeks but I feel there are other things caught in limbo until we
> >>>>> reach some consensus.  I don't think we are plagued by major
> >>>>> disagreements but rather the different facets of complexity for
> >>>>> the range of things we want to capture and make understandable
> >>>>> to a wider audience.
> >>>>>
> >>>>> So I think we need a plan for how to proceed.  The elements of
> >>>>> such a plan would cover
> >>>>> 1. capturing the different facets;
> >>>>> 2. capturing where in the document these facets currently live;
> >>>>> 3. work a consistent understanding that covers all the facets.
> >>>>>
> >>>>> Unfortunately, this is not an 80-20 situation because a standard
> >>>>> that only covers 80% of the scope is looking for trouble.
> >>>>>
> >>>>> Now I would suggest an extended call (all day?) but I realize we
> >>>>> are all busy and that may not be feasible.  What's more is it
> >>>>> may not be productive unless we have all the background material
> >>>>> together going in.
> >>>>>
> >>>>> As a precursor to an extended meeting (or even a regular
> >>>>> meeting), is it possible for us to have a short list of
> >>>>> questions and for the author of each section to satisfy items 1
> >>>>> and 2 above through the answers?  Would that be enough to help
> >>>>> structure a productive (and hopefully not too long) call?
> >>>>>
> >>>>> I haven't yet considered the questions, but figured I'd float
> >>>>> the idea and see if someone came up with something better.
> >>>>>
> >>>>> Ken
> >>>>>
> >>>>>
> >>>>>
-----------------------------------------------------------------------------
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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